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Programmers Manual - RSAP

1. Encroachment Location Hazard Statistics Veh Num of Collisions of Penetrations Rollover after Redirection Name Num EFCCR EFCCR C C E EFCCR E 5 SEG ALT DIR SIDE Type Encroach TS NTS capacity RSAP of rollovers EFCCR EFCCR C C E EFCCR E 1 1P _ R T 10 EdgeOfMedian 1 0 00000 _ 0 0000 0 0000 0 00000 0 00000 0 0000 _ 0 0000 1 1 P_ R c 10 EdgeOfMedian 1 0 00000 _ 0 0000 0 0000 0 00000 0 00000 0 0000 _ 0 0000 1 afp L T 40 EdgeOfMedian 1 1 33781 17 4979 0 0000 0 0765 0 43745 0 03345 0 0000 17 4979 1 ijp L c 40 EdgeOfMedian 1 1 11484 17 4979 0 0000 0 0637 0 43745 0 02787 0 0000 17 4979 1 1Jo__ R T 10 EdgeOfMedian 1 0 00000 0 0000 0 0000 0 00000 0 00000 0 0000 _ 0 0000 1 1Jo__ R c 10 EdgeOfMedian 1 0 00000 _0 0000 0 0000 0 00000 0 00000 0 0000 _ 0 0000 1 tjo L T 40 EdgeOfMedian 1 0 00000 _ 0 0000 0 0000 0 00000 0 00000 0 0000 _ 0 0000 1 ijo L c 40 EdgeOfMedian 1 0 00000 0 0000 0 0000 0 00000 0 00000 0 0000 _ 0 0000 1 ilp R T 10 EdgeOfMedian 2 0 00000 0 0000 0 0000 0 00000 0 0000000 _0 0000 _ 0 0000 1 1P R c 10 EdgeOfMedian 2 0 00000 _0 0000 0 0000 0 00000 0 00000 0 0000 _ 0 0000 1 iP L T 40 EdgeOfMedian 2 0 00000 0 0000 0 0000 0 00000 0 0000000 __0 0000 _ 0 0000 1 ijp L c 40 EdgeOfMedian 2 0 00000 0 0000 0 0000 0 00000 0 00000 0 0000 _ 0 0000 1 1o R T 10 EdgeOfMedian 2 0 00000 0 0000 0 0000 0 00000 0 00000 0 0000 0 0000 1 1Jo__ R c 10 EdgeOf
2. 0 0 2 0 4 0 6 0 8 1 1 2 1 4 1 6 Rollover Ratio Figure 41 Probability model for trucks rolling over longitudinal barriers If vehicle type truck _ And hazard type line _ And vehicle c g gt hazard height _ And hazard height gt 2 0 _ And hazard height lt 7 5 _ C 128 And v gt 0 Then Call subRolloverBarrier s 0 B 8 shift 1 4 PRB 1 s 2 Application Tanh ratio shift B 1 s 2 s Compute change in velocity due to loss of energy during impact change in energy during redirection along barrier DeltaKEred ke Sin Abs Theta If ke DeltaKEred PEroll gt 0 Then vOrv 2 m ke DeltaKEred PEroll 0 5 Else vOrv 0 End If Else PRB 0 End If The probability of rolling over the barrier is dependent on whether or not the vehicle penetrated the barrier upon impact WRV PRB 1 WP Probability of Rollover After Redirection If the vehicle doesn t penetrate the barrier and doesn t roll over the barrier during redirection the next possibility is that the vehicle rolls over as it is redirecting from the barrier Redirection is not considered for Point hazards or for motorcycles The probability of passenger vehicles rolling over after redirection is determined solely from crash statistics whereas the probability of trucks rolling over after redirection is determined based on impact conditions vehicle characteristics and
3. 19 see http regs dot gov 22 23 24 RSAP Root Directory C Program Files RSAPv3b 25 an M 4 h Project Information Traffic Information Road Segments Alternatives Severity Cross Section Encr Freq and 4 ial Ready Count 5 eo m 100 Figure 3 Project Information Worksheet Change Method Whenever a value on the Project Information worksheet is changed this method is activated It simply checks to see if shPrjInfo Range B5 has a value If it does the Traffic Info gt button is made visible If there is no value the Traffic Info gt button is hidden btnNewPrj_Click The purpose of this method is to allow a user to clear any data from the worksheet and start a new fresh project The method is executed by pressing the Start a New Project button shown in Figure 4 The method first notifies the user that all user entered information in the workbook will be removed and the RSAP defaults restored using a standard vbYesNo message box If the user responds No the method exits If the user responds Yes the following steps take place Notify user all data will be deleted in a Msgbox and ask if they want to proceed If user_response YES then Turn off event processing Turn off screen updating Unprotect all user input sheets Clear the content of user input cells of each worksheet Restore the RSAP defaults by copying the appropriate ranges from shDefaults to
4. SUM G ROW J ROW G IF D ROW gt E14 G13 PRODUCT B 40 ROW D 40 ROW H 40 ROW N 40 ROW H IF D ROW gt E14 H13 PRODUCT B 40 ROW D 40 ROW H 40 ROW N 40 ROW I IF D ROW gt E14 113 PRODUCT E 40 ROW N 40 ROW J IF D ROW gt E14 J13 PRODUCT E 40 ROW N 40 ROW The formula in column A simply writes the appropriate segment number starting with segment 1 in ROW 14 based on the total number of segments as listed in cell D64 The formulae in columns G through J calculate the adjusted number of expected encroachments for each encroachment type i e PR PL OR and OL The adjustments are multiplied together in the PRODUCT statement and then multiplied by the total encroachments in column E and multiplied by the proportion attributable to the particular encroachment from ROW 13 The column F formula sums up the total number of encroachments based on the estimates for the four types of encroachments listed in columns G through J provided that the segment number in column D is not blank Activate Method Selecting the Highway tab on the RSAP Dialog Controls or the Road Segments tab in the Excel worksheet tabs instantiates the shRdSegs Activate method In the case of shRdSegs RSAP sets frmRSAPcontrols mpControls value 2 to shift to the appropriate control form makes the default buttons visible i e the view shown in Figure 9 and then changes
5. L Then sideEnd 1 Else sideEnd 1 End If The next step is to determine the type and name of each hazard in each alternative This information is read directly from the worksheet Alternatives except for rollover hazards which are defined explicitly in the program If K gt oNum_Hazards iAlt Then oHzrd_Name iAlt K Rollover Else oHzrd_GenType iAlt K read general hazard type oHzrd_Name iAlt K read hazard name End If The repair cost severity penetration rollover vault statistics redirection after rollover statistics capacity height and category are then read from the worksheet C 90 Severity RSAPv3 searches each row of the Severity worksheet until it finds the corresponding hazard then reads the pertinent information m 4 Starting row with data in the Severity worksheet Do Until shSeverity Cells m 1 value oHzrd_Name iAlt K m m _1 Loop oHzrd_Type iAlt K read hazard type oHzrd_EFCCR65 iAlt K read hazard severity EFCCR65 oHzrd_Prcnt_PRV iAlt K read percent of PRV oHzrd_Prcnt_RR iAlt K read percent rollover after redirection oHzrd_Capacity iAlt K read hazard capacity oHzrd_Height iAlt K read hazard height The next step is to determine the location of the hazard If the hazard is a line hazard then the program reads the start and end coordinates of the hazard from worksheet Alternatives computes the slope between the two po
6. Number of Lanes Adjustment for opposing direction o_numLaneAdj adjust shEncrAdj M5 Col numLane numLanePrim debugFlag Opposing Direction Grade Adjustment o_gradeAdj adjust shEncrAdj AG5 1 p_grade debugFlag Opposing Direction Horizontal Curve Adjustment o_hcurvAdj adjust shEncrAdj AK5 1 p_hcurv debugFlag Else o_numLaneAdj 0 o_gradeAdj O o_hcurvAdj 0 End If Shoulder Width Adjustment shldrWidthAdj adjust shEncrAdj Y5 col shldrWidth debugFlag Access Density Adjustment accessAdj adjust shEncrAdj E5 Col access debugFlag Rumble Strip Adjustment shEncrAdj Select Range I5 Select Do Until Selection value rumble Selection offset 1 0 Select Loop rumbleAdj Selection offset 0 Col If debugFlag True Then MsgBox For amp CStr rumble amp adjustment is amp CStr rumbleAdj amp End If Terrain Adjustment shEncrAdj Select Range AC5 Select Do Until Selection value terrain Selection offset 1 0 Select Loop terrainAdj Selection offset 0 1 C 55 If debugFlag True Then MsgBox For amp CStr terrain amp adjustment is amp CStr terrainAdj amp Loop calcBaseEncr End If Write the adjustments back on shRdChar shRdSegs Select shRdSegs Unprotect shPrgData Range B6 value Range A71 Select Selection offset seg 1 0 Select Selection offset 30 1 value p_gradeAdj Se
7. Then For K 1 To total number of hazards for the current alternative If logic_1 K true Then If oHzrd_Type iAlt K P Then Hy0 oHy iAlt K 1 The program only looks for collisions when the longitudinal coordinate of the path is within the effective radius of the hazard 1 e radius of hazard plus swath width of vehicle It then computes the lateral coordinate of the trajectory path based on the current increment of the path and the encroachment point and the distance from the current path location to the center of the hazard If x gt oHx effective radius of hazard _ And x lt oHx effective radius of hazard _ And y lt gt Then yp traj iVeh i j num_pre yO D x oHx iAlt K 1 2 yp Hy0 2 0 5 The criterion for impact is then If current trajectory point D is found to be within the effective radius of the hazard and the previous trajectory point dO was outside this radius then impact occurred Otherwise impact has not occurred or the impact occurred during a previous increment and has already been accounted for If D lt effective radius of hazard _ And d0 K gt effective radius of hazard Then C 121 If a collision has occurred and the current path is not a redirection path then 1 compute probability and associated costs of a rollover occurring prior to the collision with the hazard 2 compute crash statistics and associated costs for collision with th
8. gt Results Profile Defaults ProgramData lt TrajectoryGridi TrajectoryGrid2 i 4 u Figure 17 Results Worksheet Benefit Cost Report View C 40 The Results worksheet has several built in formulae as discussed below All the formulae are below row 8 ROW in the following list indicates the ROW number Column Formula J IF B ROW VLOOKUP D ROW Severity A4 H201 3 FALSE K IF B ROW VLOOKUP D ROW Severity A4 H201 4 FALSE F ROW W IF V ROW gt Alternatives C7 X7 X IF V ROW Alternatives I7 Cells in column J below row 8 include the formula shown above The formula uses the VLOOKUP function to lookup the annual maintenance cost of each hazard in the Feature Report The hazard annual maintenance cost is listed in column C of the Severity worksheet Similarly cells in column K below row 8 use the VLOOKUP formula to lookup the average repair cost for each feature and then multiply that value by the number of crashes with the feature shown in column F In both cases the lookup is only performed if the segment value in column B is not blank The formulae in columns W and X are part of the Segment Report Both only display if the Alternative number shown in column V is not blank Column W calculates the annualized construction cost by reading the total alternative construction cost from row 7 of the Alternatives worksheet and multiplying it by the ra
9. vehicle type barrier type i e rigid semi rigid flexible etc vehicle damage e g wheel assembly damage vehicle to barrier interaction e g snagging and driver reaction to name a few In the context of an RSAPV3 analysis however only three factors are considered impact angle barrier type and vehicle type The influence of each of these factors is discussed in more detail in the ENGINEER S MANUAL The basic procedure is to 1 Determine the redirection speed 2 Select redirection paths path coordinates relative to barrier s local reference frame 3 convert path coordinates to the global reference frame and 4 send each selected path to ModulePOCanalysis to evaluate for secondary collisions Input Variables The following are a list of variables passed from the parent module and used in this subroutine e CSRL collision side of barrier right or left e K hazard number e iALT current alternative e iVeh current vehicle number e iDir current traffic direction e oHzrd_GenType general type of hazard e g bridge rail Guardrails_Rigid etc e POR probability of redirection e Theta impact angle e Theta_Haz angle of hazard relative to roadway e v impact velocity e VehCharac 1 RSAPv3 vehicle name e WVehCharac 2 FHWA vehicle class e WVehCharac 3 percent of traffic mix e WVehCharac 4 RSAPv3 vehicle type M C T e WVehCharac 5 vehicle weight e WVehCharac 6 vehicle lengt
10. Normal 2 to prevent input Set the style of the Detailed Cross Section Input area to Input If the name selected lt gt blank then Call moduleXsection writeXsectionInfo Else Tell the user to select a cross section End if Enable screen updating Enable event processing Make btnSaveXsection visible Make btnDeleteXsection visible Protect shXsection When the macro finishes executing the user input area for detailed cross section information is prepared with the appropriate cells being highlighted yellow indicating user input is needed Control stays with the user on the worksheet until either the Save or Delete buttons are selected IbxXsectionNames_Change This macro simply repaints the list box whenever anything is changed such that the view is always current MODULEXSECTION While the macros in this module are not a part of frmRSAPcontrols they are discussed here because their only function is to support the control buttons on the X Section tab of frmRSAPcontrols The module consists of the following four macros build XsectionListBox This macro is called whenever mpControls is set to 4 and It builds the list that is displayed in the IbXsectionNames shown in Figure 13 The list is stored in a hidden portion of shXsection in column 32 starting in row 15 Starting in row 15 of column 32 Look at each row until a blank cell is found The cell above the blank is the last row Name the range from row 14 to the last row
11. gt Results Profile Defaults lt ProgramData lt TrajectoryGridi lt TrajectoryGrid2 i 4 u i Figure 15 Results Worksheet Feature Report View The Results worksheet contains three reports The Feature Report shown in Figure 15 is the initial view shown The Segment Report is shown in Figure 16 and the Benefit Cost Report is shown in Figure 17 These reports are viewed by selecting the appropriate button in the RSAP Controls Dialog shown in Figure 18 as will be described shortly C 39 Page Layout Formulas Data Review te Feature Maintenance Cost S T ul v w Xx uf SEGMENT AND ALTERNATIVE COST SUMMARY Concrete Barrier Example Problem Based on Analysis Run on 8 31 2012 8 01 05 AM RSAP 3 0 0 beta Rev 120815 running in Excel Version 14 0 on Windows 32 bit NT 6 01 ANNUAL SEGMENT SUMMARY 7 mee Alternative1 622 115 622 115 o 106 084 Alternative2 30 369 41 171 106 084 5 343 46 583 26 493 Alternative3 41 171 439 Alternative4 4 15 26 493 408 Annual Crash Cost 17 M 4 gt bl Results lt Profile lt Defaults _ Program Data lt TrajectoryGrid1 lt TrajectoryGrid2_ AD AE AF AG AH EQUIVALENT ANNUAL INCREMENTAL BENEFIT COST Concrete Barrier Example Problem Based on Analysis Run on 8 31 2012 8 01 05 AM RSAP 3 0 0 beta Rev 120815 running in Excel Version 14 0 on Windows 32 bit NT 6 01 With Respect to Alternative Best Choice is 17 M 4
12. value oHzrd_Name iAlt K shPOCscratch Cells Row H value K hazard number shPOCscratch Cells Row I value EFCCR_tot K shPOCscratch Cells Row J value impact_Count_TS K shPOCscratch Cells Row K value impact_Count_NTS K If impact_Count_tot K lt gt 0 Then shPOCscratch Cells Row L value EFCCR_tot K _ impact_Count_tot K End If shPOCscratch Cells Row M value impact_Count_tot K num_traj_tot shPOCscratch Cells Row N value EFCCR_tot K If K lt oNum_Hazards iAlt Then shPOCscratch Cells Row P value count_pene K rollover after redirection from hazard k statistics If count_RR K lt gt 0 Then shPOCscratch Cells Row O value count_RR K shPOCscratch Cells Row R value EFCCR_RR K shPOCscratch Cells Row S value EFCCR_RR K _ count_RR K shPOCscratch Cells Row T value count_RR K _ num_traj_tot shPOCscratch Cells Row U value EFCCR_RR K _ num_traj_tot End If End If Row Row 1 Next K next hazard End If Next iDP next departure point station Next iVeh next vehicle type Next iAlt next roadside alternative Next iLDS next encroachment side Next iDir next traffic direction Next iSeg next segment End Sub Table 4 Example Output to POC Scratch worksheet SCRATCH SHEET FOR COLLISION PROBABILITY AND COST
13. 1 define the current x coordinate relative to the departure point Xo 2 define the longitudinal increment of the trajectory path and 3 computes the velocity based on initial velocity deceleration and distance traveled F Do While j lt nopc And logic_2 true And v lt gt 0 And POC gt 0 001 j j 1 x trajx iVeh i j num_pre x0 x coordinate If j 1 Then dx trajx iVeh i j num_pre Else dx trajx iVeh i j num_pre trajx iVeh i j num_pre 1 End If If the lateral coordinate at x is blank then the end of path is reached and the velocity is zero otherwise compute velocity If traj iVeh i j num_pre lt gt Then Liss yj Har ax length of current increment TL TL Lj cummulative length of path Deceleration is pre defined for each trajectory case in Trajectory database In some of those cases however the deceleration is considered to be unreasonably low particularly for the case of long trajectory paths Itis assumed that if a person is not braking before the vehicle leaves the roadway then braking should initiate as soon as the driver is aware of the situation The original value for deceleration from the trajectory database is used to compute velocity until the encroachment reaches a critical distance At that point if the deceleration is less than the 20 percentile deceleration value of 6 4 ft s then the velocity from that point on is computed using 20 percentile
14. Results Worksheet iinis isnie noesa eiieeii E E Ea EEEE E aE t 38 STA E E E E E E EE E E eae 43 Hazards Worksheet tseananonuae hin a a a E een See 45 E croachment Modul sries tnae E E E E E EE EE io 50 PROC SIT sac EEEE E A E E E T 50 Crash Prediction Mod le n crerssieciiinrsiesdnnsinie eina r ar aE pasai 59 Introduction ay gos bind cs Rice a n ease a a Ea eE a E a 59 Mod le POCMAIN siinse a na aa a a ashe N T S RES 60 Mod le POC a E E E asa Nila Sclete ieh Da OLR a 87 ModulePOC tay i 0 Oe eee GS CON Gita a eee Cea 93 IModulePOC anal ysis issue cal els facta edad ade ela Ste alten Sod ene ed Saas te nailed set 105 Severity Mod le sssini a E desea canes eegacny E E E 145 Benefit Cost Mod l sisinsnandrncsnnsenninannnni auna n u i 146 Proc dure e casi cto onsayngeidcasnsieceacanal adnan u ae aa a e E EAE Eas aa eT EDE EEK NO 146 Development and Maintenance Tools sicceis3i os scasavcaaasspveatecaaaiaioneateoccatorsaainceoaates GMC IUSIONIS Ena ET E E E EE te sda ed tea E A a a e a Bost References C 2 LIST OF FIGURES Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 Figure 22 Figure 23 Figure 24 Figure 25 Figure 26 Figure 27 Figure 28 Figure 29 Figure 30 Figure 31 Figure 32 Figure 33 Figure 34 Figure 35 Figure 3
15. SegEnd SegStart Expanded View Showing Settings total length of segment num_Departure_Incs Integer Value of SegLength DP_inc The number of directions the number of departure sides and the median width is determined based on Highway type There are three roadway types in RSAPv3 1 divided roadway 2 undivided roadway and 3 one way roadway as illustrated in Figure 24 Figure 25 and Figure 26 respectively A divided highway as shown in Figure 24 has two directions of traffic Primary and Opposing separated by a median whose width is determined from the RSAPv3 worksheet named Road Segments For each direction of traffic there are two possible encroachment options left side encroachments and right side encroachments Right side encroachments initiate from the edge line of the right most lane of traffic with respect to C 69 the direction of traffic and encroach directly onto the roadside Likewise left side encroachments initiate from the edge line of the left most lane of traffic with respect to the direction of traffic and encroach directly onto the median The lateral offset for divided highways is measured with respect to the center line of the median Opposing Right Encroachments a w D 24 e a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a N 36 D Primary Right Encroachments Figure 24 Illustration of encroachment locations for a divided roadway Lateral Offset f
16. Select Case hwyType Case U gt Col 1 Case D gt Col 2 Case O gt Col 3 Case Else Invalid highway type gt Exitt End select baseEncr adjust shEncrAdj A5 Col ADT FALSE this calls the adjust function which looks up the appropriate base encroachment rate from the look up table on shEncrAdj baseEncr baseEncr segmentLength 5280 the lookup table value is in units of encr mi yr so this adjusts the rate based on the actual segment length Write baseEncr in column 5 End if Loop proceed to the next segment until there are no segments left segChars This subroutine is activated by pressing the Segment project button on the Highway tab of the RSAP controls dialog Prior to calling this subroutine the style of the input area i e shRdSegs Range A98 B587 is changed to Normal 2 to prevent further use input and the Road Characteristics Table i e shRdSegs Range B71 C90 G71 V90 is cleared to prepare it for new data The macro sortRoadChars is then called to sort the characteristics into homogeneous segments and then this macro is called sortRoadChars This subroutine is activated by pressing the Segment project button on the Highway tab of the RSAP controls dialog Prior to calling this subroutine the style of the input area i e shRdSegs Range A98 B587 is changed to Normal 2 to prevent further use input and the Road Characteristics Table i e shRdSegs Rang
17. The mpControl method also calls the macro moduleXsection buildXsectionListBox which creates the list shown in IbXsectionNames as discussed below The X Section view of RSAP Controls shown in Figure 13 Figure 4 includes four command buttons and a selection list dialog box which will be described below The C 30 user can either select buttons on the RSAP control form or select a yellow or rose user input cell on the worksheet in order to enter information Activate Method Selecting the X Section tab on the RSAP Dialog Controls or the Cross Section tab in the Excel worksheet tabs instantiates the shXsection Activate method The method first disables event handling unprotects the sheet sets mpControls 4 and hides columns AF BR The number of alternatives is read from shAlternatives Range C3 value the highway type is read from shRdSegs Range E5 value and the number of segments is read from shRdSegs Range D64 value These values are used in formatting the input area The input areas in D5 H24 and columns J Z are first set to style Normal 2 to prevent user input and any values are cleared Next For i 1 to Number of Alternatives The default value shown of shAlternatives for that Alternative is copied The cell style is set to Input 2 to allow for user input Next Alternative Show segment characteristics for segment 1 initially Copy the data in shRdSegs row 71 to D26 D31 Onc
18. below C 43 Initially Hidden Buttons btnDefaultScreen_Click Sa btnNextStepHintOff_Click btnHomeDir_Click btnNextStepHintOn_Click Figure 19 RSAP Controls Dialog Settings btnDefaultScreen_Click The Excel application window can be maximized minimized resized or moved while RSAP is active The RSAP Controls Dialog can not be re sized but it can be moved interactively anywhere on the desktop Pressing the Reset Default Screen Settings button returns the display to its default RSAP configuration 1 e see Figure 1 with the RSAP controls in the upper left of the application window and the worksheet view maximized within the application screen C 44 btnNextStepHintOff_ClickQ Selecting the Verbose Mode Off on this form executes this method which hides the next step hint at the lower left of the RSAP Controls Dialog 1 e IbINextStepHint It also Selecting this option also hides the message display area of the Progress Bar form that is shown while the analysis is running btnNextStepHintOn_Click The verbose mode is actually a toggle so if Verbose Mode Off is selected it is replaced with the initially hidden button Verbose Mode On shown in Figure 19 Selecting this button turns the verbose mode back on by un hiding the IbINextStepHint box and re sizing the frmProgressBar such that the run time messages appear btnHomeDir_Click The default condition for RSAP is to be installed in
19. divided Then If iLDS 1 And iDir 1 Then yO oMedianHW oRoadWPR iDir If iLDS 1 And iDir 1 Then yO oMedianHW oRoadWOP iDir If iLDS 1 Then yO oMedianHW iDir Elself hwyType undivided Or hwyType one way Then If iLDS 1 And iDir 1 Then yO oRoadWPR iDir If iLDS 1 And iDir 1 Then y0 oRoadWOP iDir If iLDS 1 Then y0 0 C 78 End If The following lines of code compute the slope between each breakpoint of the cross section terrain and determine the sign of the slope based on its location relative to the encroachment point For i 1 To number of slope break points CSglob i 3 1 If CSglob i 1 gt yO Then negative slopes go downhill as y increases CSglob i 3 CSglob i 2 CSglob i 1 2 _ CSglob i 1 CSglob i 1 1 Else Negative slopes go downhill as y decreases Ifi 1 Then Slope is equal to adjacent slope at extents _ beyond the most negative defined point CSglob i 3 CSglob i 2 CSglob i 1 2 _ CSglob i 1 1 CSglob i 1 Else CSglob i 3 CSglob i 1 2 CSglob i 2 _ CSglob i 1 CSglob i 1 1 End If End If Baseline Probability and Adjustment Factors The next step is to determine the baseline probability of rollover for each cross section slope This task is accomplished using linear interpolation of the probability of rollover table which was previously stored in array PRslope The value of the baseline
20. uses crash data directly to determine probability of impact and probable impact conditions e g speed angle orientation etc and is thus a deterministic method i e given the same input it will always provide the same result Each trajectory path in the database is examined point by point to determine if it intersects the location of a hazard RSAP then computes the probability of impact based on the ratio of total number of impacts divided by total number of trajectory paths C 59 MODULE POCMAIN ModulePOCmain is the Probability of Collision module and serves as the main program that controls the program flow for computing probability of collision The probability of collision is determined by assessing each reconstructed trajectory path point by point for interaction with each roadside hazard and terrain feature The flow chart for this program module is shown in Figure 22 The first step in the calculations is to read in basic project information including roadway type roadway characteristics and traffic data for each roadway segment The second step is to read in the roadside cross section geometry and the type and location of each hazard to be analyzed for each set of alternatives This task is performed in Module POChaz The third step is to select relevant trajectories from the crash reconstruction database in RSAPv3 This task is performed in Module POCtraj The database is searched to identify crash cases that have roadway and
21. 40 EdgeOfMedian 1 0 00000 0 0000 0 0000 0 00000 0 00000 0 0000 0 0000 1 2 P_ R T 10 EdgeOfMedian 2 0 00000 0 0000 0 0000 0 00000 0 00000 0 0000 _ 0 0000 1 2 P_ R c 10 EdgeOfMedian 2 0 00000 0 0000 0 0000 0 00000 0 0000000 _0 0000 0 0000 1 2 p L T 40 EdgeOfMedian 2 0 00000 0 0000 0 0000 0 00000 0 00000 0 0000 _ 0 0000 1 2P L c 40 EdgeOfMedian 2 0 00000 0 0000 0 0000 0 00000 0 00000 0 0000 0 0000 1 2jo R T 10 EdgeOfMedian 2 0 00000 0 0000 0 0000 0 00000 0 00000 __ 0 0000 _ 0 0000 1 2o R 10 EdgeOfMedian 2 0 00000 0 0000 0 0000 0 00000 0 00000 0 0000 0 0000 1 2o L T 40 EdgeOfMedian 2 1 29183 15 7967 0 0000 0 0818 0 39492 0 0322958 _0 0000 15 7967 1 2o JL 40 EdgeOfMedian 2 0 01131 _ 0 1433 0 0000 0 0789 0 00358 0 00028 0 0000 0 1433 1 21P IR 10ITL2EShaneGR 2 ANNANN NANNNAL NANNANN 0 00000 0 90000 ANNANN ANNNN C 86 MODULEPOCHAZ This module is called by ModulePOCmain to gather information about each hazard and then processes the hazard data so that it can be readily accessed during the analysis The program 1 reads hazard information from worksheet Alternatives such as hazard type and location 2 searches for the hazard type on worksheet Severity to gather data necessary for the analysis such as severity capacity repair cost etc 3 defines the longitudinal barrier associated with each end terminal and 4 stor
22. CSloc i 1 CSloc i 2 i i 1 Else z j CSloc i 3 delta_y z j 1 End If zmaxp Application Max zmaxp Abs z j Next j C 96 The program then reads in the cross section profile for each case in the trajectory database and computes the slope between break points Note that there are eight y z coordinate pairs defining each cross section profile case in the database The lateral coordinates start at column 29 AC and the vertical coordinates start at column 37 AK num_traj iVeh 0 N 1 For i 1 To Count iXsect 1 yt 0 0 zt 0O 0 Do While TrajectoryData i 29 iXsect lt gt And iXsect lt 8 yt iXsect TrajectoryData i 28 iXsect y coord of X section zt iXsect TrajectoryData i 36 iXsect z coord of X section ymaxt yt iXsect If iXsect lt gt 0 Then check and correct infinite slopes delta_yt yt iXsect yt iXsect 1 If delta_yt lt 0 01 Then delta_yt 0 01 End If compute slope st iXsect zt iXsect zt iXsect 1 delta_yt End If iXsect iXsect 1 Loop The next step is to resample each of these cross section profiles at increments of delta_y using linear interpolation and then perform a point to point comparison of each cross section to the project s cross section profile by summing the square of the errors at each point For i 1 To Count yy 0 yt 0 zz 0 zt 0 SumErrSq 0 initialize the sum of the errors squared val
23. Criterion A If impact severity is greater than the structural capacity of the barrier and the structural capacity is greater than or equal to zero then the probability of penetration is determined based on a combination of impact mechanics and a pseudo probabilistic model where the probability of penetration up to capacity is based on crash statistics i e PRV from RSAPv3 severity worksheet and increases toward 100 as impact severity values increase beyond hazard capacity In this case it is assumed that the probability of penetration can be described by the hyperbolic tangent function defined below More details on the development of the hyperbolic tangent probability model are presented in the ENGINEER S MANUAL P Penetration collision 1 PRV IS 1 PRV tanh s5 __ 5 2 Capacity 2 Theta Abs Theta0 impact angle Capacity hazard capacity Convert ft lb energy m vehicle weight 32 2 lb ft s2 vehicle mass KE 1 2 m v 2 kinetic energy ISeverity 1 2 m v Sin Theta 2 Impact Severity If capacity gt 0 And ISeverity gt capacity Then s oHzrd_Prent_PRV iAlt K 100 s PRV B 5 shift 1 5 Ifs lt 1 And capacity gt 0 Then WP 1 s 2 Application Tanh ISeverity capacity shift _ B 1 s 2 s Percent penetration Else WP s End If modified velocity due to loss of energy during penetration vp 2 m ke capacity 0 5 Criterion B
24. DisplayFormulaBar False shSeverity Protect shPrgData Range B6 value shPrgData Protect shPrgData Range B6 value shPrgData Visible xlVeryHidden Application ExecuteExcel4Macro SHOW TOOLBAR Ribbon false Re start RSAP with gt StartRSAP Else Unload frmRSAPcontrols gt stops execution of RSAP Restore usual Excel display settings Active Window DisplayHeadings True Application DisplayFormulaBar True shSeverity Unprotect shPrgData Range B6 value Application Execute Excel4Macro SHOW TOOLBAR Ribbon true End If EditSheet This macro is very similar to editSeverities the only difference being that the hazard validation binding for the menus are not rebuilt The macro simply turns the Excel edit mode on and off This macro is also a toggle where the key stroke CTRL SHIFT E is used The first toggle returns the control to the usual Excel functionality and the second toggle puts the system back into RSAP mode and restarts C 150 RSAP The marco works on whatever worksheet is active at the time the toggle is selected The procedure is as follows Select the ActiveWorksheet Detect the mode by whether the display headings are on or off If ActiveWindow DisplayHeadings True Then gt turn off edit mode and re start Set the display back to usual RSAP mode shSeverity Select Active Window DisplayHeadings False Application DisplayFormulaBar False Actuve Worksheet Protect shPrgData Range B6 value A
25. Else i e If the impact severity is less than the structural capacity of the barrier or if the structural capacity of the barrier is zero or unknown the probability of penetration is defined solely based on crash statistics 1 e PRV and this value is used to C 127 weight the crash cost of any subsequent impacts This value is provided on the Severity worksheet in RSAPv3 Else WP oHzrd_Prcnt_PRV iAlt K 100 Energy loss is assumed to be 30 for PRV penetrations DeltaE ke 0 3 vp 2 m ke DeltaE 0 5 End If Probability of Penetration due to Rolling Over Barrier Trucks Only If the vehicle does not penetrate the barrier upon impact the next possibility is rolling over the barrier as the vehicle is trying to redirect The probability of rolling over the barrier is only considered in the analysis of truck trajectories and only when the center of gravity of the truck is higher than the top of the barrier An additional criterion is used for only considering longitudinal barriers with heights ranging from 2 0 ft to 7 5 ft height The program calls the subroutine subRolloverBarrier to compute the rollover ratio parameter which is used to determine the probability of the truck rolling over the barrier The equations in subroutine subRolloverBarrier are presented in the ENGINEER S MANUAL The probability of rolling over the barrier is then computed using the hyperbolic tangent model as shown in Figure 41
26. GetSaveAsFilename method is called which brings up a standard Windows file browser where the user indicates the desired filename and directory If the filename returned by the GetSaveAsFilename method is valid the file is saved btnExit_ClickQ This button simply issues the Application Quit method and thereby indirectly executes the workbook_BeforeClose method of Excel In RSAP the BeforeClose method C 13 simply returns the ribbon interface back to its normal Excel settings so that when the user opens a non RSAP workbook the interface will appear as the standard Excel interface IbINextStepHint Caption The last always visible feature of the RSAP Controls Dialog shown in Figure 2 is the NextStepHint label This area on the RSAP Controls Dialog is used to provide hints to the user about the next appropriate input step This is accomplished by RSAP setting a text string equal to the IlbINextStepHint Caption property of frmRSAPcontrols Many different subroutines and functions write into this text box depending on the context The user cannot enter data in this locations it is only for RSAP to write out text hints The IbINextStepHint label form can be hidden using the Verbose Mode Off button in the Settings tabs as will be described later The label is hidden by setting the form property IbINextStepHint Visible to FALSE PROJECT INFORMATION WORKSHEET The Project Information worksheet is used to collect basic project information f
27. K L ne 1 FEATURE COLLISION AND COST REPORT 2 Concrete Barrier Example Problem 3 Based on Analysis Run on 8 31 2012 8 01 05 AM 4 RSAP 3 0 0 beta Rev 120815 running in Excel Version 14 0 on Windows 32 bit NT6 01 5 Analysis Time 743 6992 sec 6 7 ANNUAL CRASHES ANNUAL COST OF CRASHES 2 2 if E st 2 g E 6 3 2 8 30 5 F 22 E H E lt 8 9 1 Alternative 1 10 21 1 EdgeOfMedian PL 0 0000 0 0000 0 0000 0 0 0 11 a S 1 EdgeOfMedian OL 2 0463 2 0463 0 0000 305 787 o 0 12 11 2 EdgeOfMedian PL 2 0269 2 0269 0 0000 293 646 o 0 13 11 2 EdgeOfMedian OL 0 0000 0 0000 0 0000 o o o 14 11 3 Rollover PL 0 1515 0 0000 0 0000 10 747 o 0 15 11 3 Rollover OL 0 1687 0 0000 0 0000 11 935 0 0 16 2 Alternative 2 17 2 i 1 EdgeOfMedian PL 0 0000 0 0000 0 0000 0 0 0 18 22 1 EdgeOfMedian OL 0 0374 0 0374 0 0000 2 948 o 0 19 2 2 2 EdgeOfMedian PL 0 0384 0 0384 0 0000 3 013 o 0 20 2 1 2 EdgeOfMedian OL 0 0000 0 0000 0 0000 0 0 0 21 22 3 TL3WbeamMB PL 2 2527 0 0451 0 0000 46 171 o 2 703 22 ad 3 TL3WbeamMB OL 2 1995 0 0440 0 0000 44 986 o 2 639 23 2 4 4 Rollover PL 0 0738 0 0000 0 0000 4 425 0 0 24 2 4 Rollover OL 0 0769 0 0000 0 0000 4 539 o 0 25 3 Alternative 3 26 3 4 1 EdgeOfMedian PL 0 0000 0 0000 0 0000 o 0 0 27 E 1 EdgeOfMedian OL 0 0037 0 0037 0 0000 314 o 0 28 3 1 2 EdgeOfMedian PL 0 0037 0 0037 0 0000 302 o o nn 2 d Ardan NfAAndian DI DODDO DOON DODOO y en en ad M 4
28. Trajectory path a crossing hazard from left side and b crossing hazard from right side C 115 The following lines of code check for impacts with line hazards unless it is connected to an end terminal that has already been struck Recall that when an end terminal is struck the end_pen_flag value is set to the hazard number corresponding to the line hazard which is attached to the end terminal Do While j lt nopc And logic_2 true And v lt gt 0 And POC gt 0 001 If yj lt gt Then For K 1 To total number of hazards for the current alternative If logic_1 K true Then If oHzrd_Type iAlt K L And end_pen_flag lt gt K Then The following lines of code determine which end of the hazard is passed first For example in the primary direction the hazard coordinate oHx is passed first whereas from the opposing direction of traffic the hazard coordinate oHx2 would be passed first If iDir 1 Then loc_checkl x dx loc_check2 x Else loc_checkl x loc_check2 x dx End If There are cases when the longitudinal length of a hazard e g line hazard perpendicular to roadway is less than the longitudinal increment of the trajectory e g 1 ft To avoid passing over such hazards the path position at a x dx is checked to see if it has passed the upstream end of the hazard and the path position at x is checked to see if it has passed the down stream end of the hazard If TRUE then check for collision
29. and subRolloverMB2 to compute crash cost statistics variables The program passes impact conditions vehicle characteristics and hazard severity information into the subroutine these data are used to compute the crash costs for the current impact which are added to the cumulative cost of impacts on the hazard The details of the development of this procedure are provided in the ENGINEER S MANUAL Input Variables The following are a list of variables passed from the parent modules and subroutines e cost_adj cost adjustment factor for current vehicle type e CS collision side e iALT current alternative e num_traj_seg cumulative number of trajectories for this segment e oHzrd_EFCCR65 e POC probability of collision e vy impact velocity e veh type vehicle type Program Variables The following are a list of variables defined in the subroutine e EFCCR Equivalent Fatal Crash Cost Ratio e g normalized crash cost e EFCCRi num_traj_seg 1 total cumulative EFCCR the current trajectory e EFCCRi num_traj_seg 2 vehicle type e EFCCRi num_traj_seg 3 alternative e EFCCR tot total cumulative EFCCR for this hazard e Impact_Count_tot cumulative number of impacts on current hazard e Impact_Count_NTS cumulative number of impacts on non traffic side of hazard current hazard e Impact_Count_TS cumulative number of impacts on traffic side of hazard current hazard Procedure Compute EFCCR for current collision based on vehicle type haz
30. barrier height An additional criterion is implemented which only considers rollover if the height of the hazard is within the range of 2 25 to 7 5 ft WRR 0 If hazard type line And v gt 0 Then It was determined from review of full scale crash tests that the typical loss of kinetic energy could be approximated by multiplying the impact energy by the sine of the impact angle DeltaKE KE Sin Abs Theta reduction in energy during redirection Vr 2 m KE DeltaKE 0 5 redirection velocity C 129 The following lines of code compute the probability of rollover after redirection for trucks If vehicle type truck _ And hazard height gt 2 25 _ And hazard height lt 7 5 _ Then The program calls the subroutine subRolloverTafficSide to compute the rollover ratio parameter which is used to determine the probability of the truck rolling over the barrier The probability of rolling over the barrier is then computed using the same hyperbolic tangent model that was shown in Figure 41 Call subRolloverTrafficSide s 0 B 8 shift 1 PRR 1 s 2 App Tanh ratio shift B 1 s 2 s The probability of rolling over after redirection is dependent on whether or not the vehicle penetrated the barrier upon impact or rolled over the barrier during redirection WRR PRR 1 WP WRV Trucks tend to only roll a quarter turn onto their side whereas passenger vehicles tend to roll multiple
31. composite score and the average composite score of the selected trajectory cases Call MatrixSort sort trajectory scores in descending order sumTrajscore 0 initialize sum of trajectories scores Do While number of selected cases lt min number Or composite score gt 0 93_ And number of selected cases lt Application Max min number max number num_traj iVeh num_traj iVeh 1 increase count of selected trajectory cases sumTrajscore sumTrajscore current trajectory score Loop minTrajscore minimum value of selected trajectory scores avgTrajscore sumTrajscore num_traj iVeh Redefine the Selected Trajectory Cases Based on Traffic Direction and Departure Side As discussed earlier the trajectory paths in the trajectory database have all been normalized to a local reference frame with positive path coordinates e g consistent with primary right encroachments The trajectory path data must be transformed to the global coordinate frame for application in the analysis The following lines of code re dimension the trajectory path variables and transform the trajectory path coordinates from local to global coordinates for each trajectory case selected for the analysis ReDim trajx num_veh num_traj iVeh num_pre iVeh 300 ReDim trajy num_veh num_traj iVeh num_pre iVeh 300 ReDim MaxL num_veh num_traj iVeh ReDim MinY num_veh num_traj iVeh ReDim MaxY num_veh num_traj iVeh For i I To
32. e Severity Prediction Module and e Benefit Cost Analysis Module Each of these four modules are implemented as a code module in RSAPv3 Each code module will be discussed in the chapters and sections below OVERVIEW The analysis technique used by RSAPV3 is based on a series of conditional probabilities First RSAPv3 predicts the number of encroachments that can be expected C 5 on a given road segment as a function of the traffic and geometric characteristics of the roadway Given an encroachment has occurred the crash prediction module then assesses if the encroachment is likely to result in a crash P CrlEncr If a crash is predicted the severity prediction module estimates the severity of the crash P SevICr The severity estimates of each crash are then calculated and transformed into units of dollars in order to compare the reduction in societal crash costs i e benefits to the direct cost of implementing the alternative i e costs The following conditional probability model is used for each alternative on each segment E CC ym ADT Ly P Encr P CrlEncr P SeviCr E CC Sevs where E CC nm Expected annual crash cost on segment N for alternative M AADT Average Daily Traffic in vehicles day Ln Length of segment N in miles P Encr The probability a vehicle will encroachment on the segment P CrlEncr The probability a crash will occur on the segment given that an encroachment has occurred P Sevs Cr The
33. focusing on how to use the software and access its features It includes several example problems that illustrate how data should be set up and entered and provides results that can be used to check a user s first runs The ENGINEER S MANUAL contains extensive explanations of the analysis methods the supporting research and data used by the software background information explanation of existing software and literature and the potential implementation of this software The ENGINEER S MANUAL also contains instructions on how to maintain modify and update the many lookup tables within RSAP so that the results of new research can be easily incorporated into the program BACKGROUND RSAPv3 uses a conditional encroachment collision severity approach to determine the frequency severity and societal cost of roadside crashes for each user entered design alternative These crash costs are then compared to the agency costs i e construction and or maintenance etc of the proposed alternatives An alternative which results in a reduction in crash costs greater than the agency costs of the improvement is considered a feasible project The alternative with the highest benefit i e reduction in crash costs to agency costs ratio is the best alternative An RSAPv3 analysis is composed of four major steps for assessing each alternative and is therefore structured into four modules e Encroachment Probability Module e Crash Prediction Module
34. iAlt 1 to alts Set the style to Input to allow user input only in cells where a valid segment and alternative have been defined in shRdSegs and shAlternatives Next iAlt C 34 Next iSeg Delete the old validation rules in D5 H24 Create a new validation rule with drop down menus pointing to the named range SlopeNames Position the cursor in cell D5 Hide btnDeleteXsection Hide btnSaveXsection Enable event processing Protect shXsection When this macro finishes the user is in control via the worksheet interface The validation rules have been re set to what is currently in the slope name database The user retains control until a button is pressed on the RSAP Controls Dialog IbIEditXsection This form component is a simple label with text identifying the list box below The user cannot select or affect this label in any way IbXsectionNames_DbIClick This form component is a list box that presents a list of cross section names that have been saved in RSAPv3 The list box is actually built when the mpControl value is set to 5 by calling module Xsection buildXsectionListBox which is discussed next Items in this listbox can be selected double clicking the name in the box Double clicking initiates this macro The procedure is as follows Unprotect shXsection Disable Screen Updating Disable Event Processing Disable the validation rules in the input area i e Range D5 H24 Set the style of the user input area D5 H24 to
35. only required information on the Project Information worksheet although there are a number of other default values that can be changed If shPrjInfo Range B5 value is not blank the Traffic Info gt button is set to visible indicating that it is appropriate to move on to the next worksheet If shPrjInfoRange B5 Value 1 e is equal to blank the Traffic Info gt remains hidden Lastly shPrjInfo is selected and control is returned to frmRSAPcontrols x MA 9 amp File Home Insert Page Layout Formulas Data Review View O gt oR BS X fe Concrete Barrier Example Problem v A B c D E F G H 1 J K 1 RSAP PROJECT INFORMATION z 3 BASIC INFORMATION 4 Today s date i e run date 8 31 2012 5 Title 6 Units uscu only USCU units at this time 7 Design Life 25 YRS 8 Construction Year i 2003 9 Rate of Return 4 be rc 2 CRASH COSTS 13 Use GDP values during life N 14 Expand to current year by GDP N 15 GDP Deflator to construction year 4 ______ GrashcostTimeline see http www gpoaccess gov usbudget fy09 hist html 17 Base year for crash cost data 2009 2003 2015 5 2028 CostUsed 18 Value of Statistical Life 6 000 000 6 000 000 6 000 000 6 000 000 _ 6 000 000 Reference for VSL Szabat and Knapp Treatment of the Economic Value of a Statistical Life in Departmental Analyses 2009 Annual Revision U S DOT March 18 2009
36. quarter turns The severity of rollovers for trucks is therefore likely to be less than severity of rollovers for passenger vehicles however the baseline severity EFCCR65 for rollovers is currently the same value for all rollover events The variable scalePOC was defined here to scale the severity for truck rollovers if when data warrant it The scale factor is applied to the ERCCR65 value as it is passed to subCollision_Statistics for use in computing rollover cost statistics scalePOC 1 KK set hazard type to rollovers Call subCollision_Statistics oHzrd_EFCCR65 iAlt KK scalePOC The following lines of code compute the probability of rollover after redirection for passenger vehicles ElseIf VehCharac iVeh 4 C Then KK set hazard type to rollovers The probability of rollover after redirection is taken as the lesser value between e One minus the percent of rollover after redirection provided on the RSAPv3 Severity worksheet and e the probability that penetration did not occur C 130 For example if it was determined that the probability of penetrating the barrier was 0 99 and the percent of rollovers after redirection provided on the RSAPv3 Severity worksheet was 0 04 then WRR would be taken as 1 0 99 0 01 WRR App Min 1 WP WRV oHzrd_Prcnt_RR iAlt K 100 Call subCollision_Statistics End If End If Probability of Redirection If the vehicle does not penetrate the bar
37. radius of the hazard and w is the width of vehicle as illustrated in Figure 39 The vehicle swath is read from the RSAPv3 worksheet named Traffic Information R ry Yew Swath Width of Vehicle w 0 2 Radius of Hazard r4 P al A u il w 2 Figure 39 Illustration Defining the effective radius R of a Point hazard The basic procedure for identifying impact with Point hazards is to compute the distance d from the path at the current increment j to the center point of the hazard and compare it to the effective radius of the hazard R If the distance to the hazard is less than R then the path is inside the boundaries of the hazard and impact has occurred as illustrated in Figure 40 It is possible that the path may fall inside the radius of the hazard at several consecutive increments along the path as illustrated in Figure 6 To avoid counting these as subsequent impacts the program checks to see if the path was inside the hazard at the previous increment j 1 If so the current increment j is not considered a collision C 120 Point Hazard Cee he Figure 40 Illustration Trajectory path crossing a point hazard The following lines of code check for impacts with point hazards The first step of this task is to compute the lateral coordinate value of the line hazard at x and at x J Do While j lt nopc And logic_2 true And v lt gt 0 And POC gt 0 001 If yj lt gt
38. readily modified to include or reduce the number of rows and columns of data without requiring any modifications to the program however it is important that that the names of these table headings are not changed since the program uses these names to identify the appropriate table on the worksheet Call subRollInput PHI grade NRgrade NCgrade Slope Grade Adjustment Call subRollInput PHIhorcurv NRhorcurv NChorcurv Slope Horizontal Curvature 1 R Adjustment C 68 Segment Characteristics and Analysis Settings This section of the program 1 reads in starting and ending RSAPv3 Controls l coordinates for each segment in the project and 2 reads in various analysis settings from the RSAPV3 CONTROL FORM including the distance between encroachment points along the roadway segment and the encroachment sides that are to be evaluated in the analysis as illustrated in Figure 23 A Encroachments DP_inc distance between IV Primary Right JV Primary Left V Opposing Right encroachment locations ft read from RSAPv3 Control Form If no value is provided for DP_inc then a default value of 4 ft is used NOS number of segments read from RSAPv3 worksheet Road Segments For iSeg 1 To NOS SegStart Start station for segment from RSAPv3 worksheet Road Segments SegEnd End station for segment from RSAPv3 worksheet Road Segments Figure 23 RSAP Controls Dialog Analyze SegLength
39. roadside characteristics that most closely match those of the current analysis case i e for current segment roadside and alternative then the vehicle trajectories from that subset of crash cases are mapped onto the roadside and or median The fourth step is to examine each trajectory for a possible interaction i e collision with a modeled hazard This task is performed in Module POCanalysis When examining a trajectory there are many possible outcomes For example a trajectory may interact with a roadside barrier then either stop in contact penetrate rollover the barrier or be redirected The probability of each of these events is then calculated and the outcome of each of these events is evaluated Continuing with the same example if the vehicle penetrates the barrier the trajectory is followed further to determine if it interacts with any other modeled hazards or results in rollover If the trajectory is redirected then redirection paths are evaluated for secondary collision events After all of the possibilities have been exhausted the selected trajectories are incremented forward a predetermined amount default value is four feet along the segment to continue the analysis The following sections discuss the steps of the analysis process in more detail C 60 Module POCMain Gather Project Information Call ModulePOChaz Hazard Type and For iSeg 1 to NOS For each Segment Locati
40. the appropriate user input worksheet Select shPrjInfo Move the cursor to cell BS Reprotect all the user input sheets Re enable event processing Re enable screen updating Set the Next button visibility to FALSE End if RSAP Controls xy btnNewPrj_Click btnOldPrj_Click btnProjinfoClear_Click btnPrjlnfoDefaults_Click btnNextTrafflnfo_Click Figure 4 RSAP Controls Dialog Project Information btnOldPrj_ClickQ This method is executed by pressing the Open Existing Project button shown in Figure 4 The purpose of this method is to allow the user to read in an already existing RSAP project file Only the input data is read in and not the results Once the data has C 16 been read in it can be either changed or analyzed using the usual procedures The procedure is as follows Notify user all data will be deleted in a Msgbox and ask if they want to proceed If user_response YES then Disable events Disable alerts Disable screen updating Unprotect all user input sheets Go through each sheet and clear all user entered data Go through each sheet and restore all RSAP defaults Open the existing file with Workbooks Open If filename lt gt FALSE then file name is valid and exists For all user input worksheets Copy user input cells from old worksheet PasteVavles user input cells into active worksheet moduleEncroachments sortRoadChars Sort the road characteristics moduleEncroacments segChars se
41. the btnUserMan_Click subroutine except the Engineer s Manual i e the file name is RSAPv3EngineersManual pdf btnRSAPhelp_Click This button opens the RSAP help file The help file is a Microsoft Compile HTML help file i e the file extension is chm The file RSAP chm is distributed with RSAPv3 and is usually located in the C Program Files RSAPv3 subdirectory RSAP first looks for the file in the location specified in the public variable moduleTools helpfile If it does not find the file there it looks in the RSAP home directory stored in the Program Information worksheet in cell B24 If the help file is not found in either of these locations an error message is displayed and the Windows default help screen appears btnSave_Click This button saves the workbook using the existing workbook name property using the ActiveWorkbook SaveAs method when the filename property is set to the current workbook name property btnSaveAs_Click This button prompts the user for a file name to save the current workbook RSAP can be started from either a macro enabled template i e an xltm file or a macro enabled workbook i e an xlsm file RSAP will not allow the user to save a project as a template only as a macro enabled workbook This prevents unintentional overwriting of the source blank workbook template The method starts by setting the current workbook name property to the temporary variable currentName The Application
42. the first i e rbtnAlt1_Click is described here Selecting the radio button shifts the view to display the user input area for the alternative selected changed the cell style for that alternative to Input and changes the cell style for all other cells to Normal 2 The user can then enter data in the yellow highlighted cells until they chose another button This macro sets the rbtnAltl value TRUE showing that the radio button has been selected and then calls the macro moduleAlternatives EditAlt 1 which sets up the formating btn ViewHazData_Click This button activates the Severity worksheet and shifts the view to the Severity worksheet i e shSeverity It also sets the mpControls value to 8 which displays the Hazard tab as shown in Figure 21 This button shifts control to the Severity tab of the RSAP Control Dialog C 29 btnPrevBuildSegments_Click This button returns the user to the Road Segments worksheet by activating shRdSegs and setting mpControls 2 The user is taken back to the previous input worksheet Any information entered on the Alternatives worksheet is saved so the user can come back to where they left off btnNextAnalyze_Click This button advances the user to the X Section worksheet by activating the Cross Section worksheet i e shXsection and setting mpControls 4 CROSS SECTION WORKSHEET The Cross Section worksheet is used to collect information from the user about the roadside
43. the roadside cross section geometry corresponding to the roadside or median at the current encroachment location 3 and then converts the cross section coordinates from the global coordinate reference frame to a local coordinate system relative to the encroachment point The information processed in this section of the program is used primarily for selecting trajectories for the analysis which will be discussed in a later section Determine Posted Speed Limit Roadway Grade and Horizontal Curve Radius Three roadway characteristics i e posted speed limit roadway vertical grade and horizontal curve radius are read from worksheet Road Segments These characteristics will be used later in the trajectory selection process The values for vertical grade and horizontal curve radius are defined with respect to the primary direction of traffic and must be redefined to correspond to the current encroachment conditions For example a positive value for highway grade defined in the worksheet Road Segments corresponds to an up hill grade for vehicles traveling in the primary traffic direction and consequently to a down hill grade for vehicles traveling in the opposing traffic direction So when evaluating encroachments in the opposing traffic direction the sign of the vertical grade from the worksheet must be reversed for the analysis Similarly a positive value for horizontal curve radius as defined in worksheet Road Segm
44. the styles of range E3 E8 to Input2 in order to accept user input and sets the styles of range A98 D587 to Normal2 to prevent user input C 23 Initially Hidden Buttons btnSegment_Click Segment Project _Prozecr btnSeeCharTab_Click Ss Encr btnSeeCharTab_Click Cear er btnAutomatic_Click btnSeeEncr_Click btnDefaults_Click btnEditWholePrjlnfo_Click btnEncr_Click btnPrevBuildSegments_Click btnNextAlts_Click Figure 9 RSAP Controls Dialog Highway Change Method Whenever a value on the Road Segments worksheet is changed this method is activated If there is input in all of the input cells i e A98 d588 E3 E5 G71 V90 and B71 c71 then the Alternative Info gt button is made visible If any of these ranges are completely blank the button is hidden This method also checks cell E5 to determine the highway type i e divided undivided or one way A case statement is used to hide or make visible the appropriate columns of the Road Characteristics Table 1 e range A63 P90 and the Encroachment Adjustments Table i e range A38 M61 C 24 The change method also checks to make sure that 100 percent of the volume is in the primary direction for one way roadways by checking cells E5 and E3 btnAutomatic_Click This macro shifts the view to the data entry area for road characteristics in shRdSegs Range A98 D587 The style for the data entry area is set to Inpu
45. the variables are then re initialized for the next vehicle type and for each encroachment side location The following lines of code are used to initialize the variables for collision statistics For K 1 To total number of hazards including rollovers impact_Count_TS K 0 impact_Count_NTS K 0 impact_Count_tot K 0 EFCCR_tot K 0 EFCCR_RR K 0 count_RR K 0 count_pene_RSAP K 0 Next K impact_total 0 Search Selected Trajectory Paths for impact with Hazard s and Compute POC The cost of collision is then determined based on the impact conditions hazard severity and probability of the collision event The program calls ModulePOCanalysis to perform the collision analysis task where each trajectory is individually examined for possible collisions with hazards the collision statistics are computed and stored in the appropriate data collectors and these data are then returned to the main program _ e ModulePOCmain for processing The programming details of the Probability of Collision analysis module will be presented in a subsequent section of this Manual The first step in this task is to determine the longitudinal coordinate of the encroachment point When the encroachments are being evaluated for the primary traffic direction the analysis starts at the beginning of the segment and evaluates each preselected trajectory path for collisions then increments forward along the segment by a predefined increment length i e
46. the vehicle type is not a motorcycle then the program calls subroutine subRedirect to evaluate redirection paths for secondary collisions Recall that the probability of redirection was determined in step 3 from subroutine subPenetrate The subroutines are presented in a later section of this Manual Since the following lines of code conclude the analysis for the line hazard all the preceding program loops and nested If statements associated with the analysis of the line hazard are presented in gray font for convenience Do While j lt nopc And logic_2 true And v lt gt 0 And POC gt 0 001 If yj lt gt Then For K 1 To total number of hazards for the current alternative If logic_1 K true Then If oHzrd_Type iAlt K L And end_pen_flag lt gt K Then If loc_checkl gt oHx iAlt K 1 And loc_check2 lt oHx iAlt K 2 Then If Collision true Then If Not oHzrd_Name iAlt K EdgeOfMedian And CS NTS If POR gt 0 01 And vehicle type lt gt M Then Call subRedirect End If End If End If C 119 End If End If Move to the next hazard and continue evaluating current path for collisions Next K Point Hazards To determine if a vehicle following a given trajectory path will encounter a Point hazard the program increases the effective radius of the hazard to account for the swath of the vehicle The effective radius of the hazard is then defined as R r w 2 where r is the
47. value The critical length is the distance that the vehicle travels during typical perception reaction time t of one second t perception reaction time If TL gt decel 2 t 2 VO t Then decel Application Max decel 6 4 prevent overflow in max length calculation below If decel 0 Then decel 0 001 The maximum length of the trajectory path MaxL was computed earlier however its value will decrease if the value for deceleration is increased and must be recomputed note this variable is used for computing probability of rollover in a later task C 112 MaxL Application Min MaxL0 VE 2 decel 1 2 If the velocity is less than zero for the current increment then set the velocity to zero If VO 2 2 decel TL gt 0 Then v VO 2 2 decel TL 0 5 Else v 0 deceleration was increased and path ended prior to reaching the end of original path definition End If Else v 0 velocity set to zero at end of path definition End If Compute Rollover Statistics and Check for Rollover Before checking the path for impact with roadside features the program first computes the probability of rollover at the current path increment unless the current trajectory is a redirection event The probability of rollover for a given trajectory path is modeled in RSAPv3 using the following relationship which is based on the average probability of rollover as the vehicle traverses multiple sideslopes along i
48. 0 There is no default information on the Alternatives worksheet and the user can define up to five different alternatives The worksheet defaults to displaying alternative 1 when activated 4 Fo amp File Home Insert Page Layout Formulas Data Review View O o os A12 v fe v A B c D E F G H I J 5 ROADSIDE FEATURES FOR ALTERNATIVE NUMBER 6 ALTERNATIVE NAME 7 CONSTRUCTION COST DEFAULT X SECTION ANNUAL MAINTENANCE COST SPECIFIC HAZARD TYPE STARTSTATION END STATION PARAMETER VALUE 8 GENERAL HAZARD TYPE 9 START OFFSET STARTSIDE END OFFSET STATIONS STATIONS M 4 Project Information Traffic Information Road Segments Alternatives Severitj 4 iu Ready moam 100 g vs Figure 10 Alternatives Worksheet Selecting the Alternatives tab in the RSAP Controls Dialog or selecting the Alternatives worksheet tab will set the frmRSAPcontrols mpControls Value property to 3 display the context sensitive buttons as shown in Figure 10and activate the Alternatives worksheet i e shAlternatives C 26 The Alternatives view of RSAP Controls shown in Figure 11 Figure 4 includes seven command buttons and two text box displays which will be described below The user can either select buttons on the RSAP control form or select a yellow user input cell on the worksheet in order to enter information Activate Metho
49. 1 hidden TrajectoryGrid2 TrajectoryGrid2 hidden e TrajectoryGrid3 TrajectoryGrid3 hidden The user interacts with RSAPv3 through the RSAP Controls Dialog box and the visible worksheets The hidden worksheets contain a variety of default data trajectory information and other data needed by RSAPv3 that the user should not normally need to see These worksheets are hidden to prevent inadvertent changes in the default data and required program information The next type of components are Forms and RSAPv3 has the following forms defined e frmRSAPcontrols this form is the primary means for the user to control the program flow C 8 frmProgressBar this form shows a progress bar during the analysis phase showing the percentage of completion as well as some trajectory selection messages frmRSAPsplash this form is a simple splash screen that appears and disappears when RSAPV3 is started frmXsectionChoice this is a minor selection input form for the selection of x section data that is called by frmRSAPcontrols RSAPvV3 is an event driven piece of software meaning that the exact process flow is determined by the user through the choice and order of buttons that are selected There is no overall flow chart of information flow since the user can move around the program in any order they wish with the exception that all input has to be complete before the Run button on frmRSAPcontrols is selected This eve
50. 6 Figure 37 Figure 38 Initial RSAPv3 Application Display 00 0 0 ceeceeesseceenceeeeececeeneeceeeeeceeeeecsneeeesaes 11 RSAP Controls Dialog tab and button bindings 0 eee eee eee esse eeeeeeeees 12 Project Information W Orksheet 2 xc Ate eee eee 15 RSAP Controls Dialog Project Information eeesesesesesereereesererrereeserereseee 16 Traffic Information Worksheet sseeseeeseeeeeseeeseseesseseresrerseseresressessresressesseesees 19 RSAP Controls Dialog Traffic Information eeeeeseeeeeeeeesrrsrreresressreeresee 20 Road Segments Worksheet Whole Roadway Characteristics Input Area 22 Road Segments Worksheet User Entered Characteristics Input Area 22 RSAP Controls Dialog Highway ceeesscesscecesnceceeececeeeeeceeeeeceeeeeesseeeesaes 24 Alternatives Worksheet sst5 fh si lsee oo cts aa rn 21 ms aides peed taut saddest teas 26 RSAP Controls Dialog Alternatives 00 0 eseceseeceseceseeeeneeeseecnaeenseeeees 28 Cross Section Worksheet cieisccsictincsns aed sesiisetuioa teenie teeeactcedeairente 30 RSAP Controls Dialog Cross Section cceecceeescceeeseeeeeeeeeeeeeeesneesenaeeees 32 RSAP Controls Dialog Analyze Condensed View 37 Results Worksheet Feature Report View sessesssesssesssssressresseessersseeeeseee 39 Results Worksheet Segment Report View ccccceeseceesseceesteeeeeteeeeneeees 40 Results Worksheet Benefit Cost Repor
51. 6 C26 Sum C13 C16 The formula in cell C6 calculates the projected AADT for the midlife using the AADT supplied in Cell C3 the traffic growth supplied in Cell C4 and half the project life previously supplied on the Project Information worksheet in cell B7 The formula in cell C7 is identical except the whole project life is used to calculate the AADT at the end of the project life The AADT used in the benefit cost calculations is shown in cell C8 based on the user s choice in cell C5 The formula in cell C26 simply sums the percent of traffic for each vehicle type A validation rule is applied such that if the value is not equal to exactly 100 00 the cell is colored red The user is not permitted to proceed until the sum is 100 00 Activate Method Selecting the Traffic tab on the RSAP Dialog Controls or the Traffic Information tab in the Excel worksheet tabs instantiates the shTraffInfo Worksheet_Activate method In the case of shTraffInfo RSAP simply checks to see if there is any input in user cells and either displays the Highway Info button if there is or leaves it blank if there is not fam oo File Home Insert Page Layout Formulas Data Review View OU ot J13 X f 0 56 v Ca A B c o Ee en Le J K I L E 1 Concrete Barrier Example Problem 2 TRAFFIC INFORMATION 3 CONSTRUCTION YEAR ADT vehicles day 4 TRAFFIC GROWTH growth yr 5 WHICH ADT TO
52. APPENDIX C PROGRAMMER S MANUAL RSAP Version 3 0 0 NCHRP 22 27 ROADSIDE SAFETY ANALYSIS PROGRAM RSAP UPDATE RoadSafe LLC 12 Main Street Canton Maine 04221 October 25 2012 TABLE OF CONTENTS TETSU OF PU QUIS oseere aspre a na sais iva Gish uealeia eae wa sparen sas doen deaaban lt dea TE Ra 3 Pist of TablesSir graniet ee E e E a a E A it cae aie tata nt ieials 4 Introd ctioh nenni innra ea a E E TAE a E A ERTE 5 Back round 0a oes Bee go Ea E A E E E eta hd nds dees E E EAO 5 OO a e seal ccs a a decouaenesseoereeeles 5 ATCO CHUNG nse sanee i a E A E RE E E cea R N 7 Background nenen ses ren e e A AE 7 RSAP Components neresna a E R E a a a a 8 CONVENU ONS a AAE E E E euch tae A Se TS 9 Poara O E CS Sra O 10 Project mp tandControh zeae e Neath cet ated a E E E cites 11 RSAP Controls Dial g BORXscssunecisorninnna e a a a 11 Project information WoOrksheet sicissccsassessacsserndcesssseadeadedeiecs aagecaenaeedaasaausead coandedesasesouans 14 Traffic Information WOrk SHEL ec sssceinenaeasacsiuvetaaytganiaeagiadechsnoensdeagnadayon haccaareqbedaghouaesanes 18 Road Segments WOEKSNE EL 5 sSicaccicesiccuc aaa ecov aut anede coy A L A E O R ES 21 Altermnatives Worksheet munien alias sasocoi ch tatace mbgalebei cma seant Aten gatlirataaseSieales 26 Cross Section Worksh et crenhent nnen ta pnadndsdenconadancaue e Ea aa ai 30 mod le XSCCUOM sarsana an a a RE e A sashes G n a 36 Analyt oie ae var a a a i atg eere aa ar garse 36
53. C Program Files RSAPv3 Sometimes users do not have administrative privileges on their computers so they are not able to install RSAP in that location Since RSAP is simply a macro enabled Excel workbook it does not really need to be installed the workbook can be copied to any location on the user s computer The only disadvantage to putting an RSAP workbook in another location is that RSAP does not know the location of the User s Manual Engineer s Manual and help file Selecting the Change RSAP Home Directory brings up a directory selection browser The user can select any subdirectory and the path to that subdirectory is saved in cell B24 of the Project Information worksheet As described earlier if the User s Manual Engineer s Manual or help files cannot be found in C Program Files RSAPv3 the directory listed in shPrjInfo Range B24 value is then searched HAZARDS WORKSHEET The Severity worksheet shown in Figure 20 is a database of all the hazards that can be used in RSAPv3 The Severity worksheet can be accessed either by selecting the Hazard tab on the RSAP Controls Dialog or selecting the Severity worksheet tab The user is not allowed to make changes to the Severity worksheet but reviewing it can be useful C 45 A FO o File Home Insert Page Layout Formulas Data Review View O o Gis KS vE fe BridgeRails A B c D E F G H I J K 1 HAZARD CHARACTERISTICS TYPICAL REPAI
54. CCRi is an array variable that stores the individual crash cost of each trajectory path Calculate and Write Average Crash Costs to Worksheet The following lines of code compute the average crash costs associated with each hazard at the end of each segment analysis as well as other collision statistics For example the average crash cost on a particular hazard is computed as the total crash cost of all collision on that hazard divided by the total number of encroachments These values are written to the POC Scratch worksheet and are later used for generating the Feature Report Segment Report and B C Report on the Results worksheet in RSAPv3 An example of the output to the POC Scratch worksheet is shown in Table 4 For iSeg 1 To NOS For iDir 1 To 2 Step 2 For iLDS 1 To 2 Step 2 For iAlt 1 To num_Alts For iVeh 1 To num_veh For iDP 0 To num_Departure_Incs If iDP num_Departure_Incs Then For K 1 To oNum_Hazards iAlt 1 shPOCscratch Cells Row A value iSeg shPOCscratch Cells Row B value iAlt If iDir 1 Then shPOCscratch Cells Row C value P Else C 83 num_traj_tot shPOCscratch Cells Row C value O End If If iLDS 1 Then shPOCscratch Cells Row D value R Else shPOCscratch Cells Row D value L End If shPOCscratch Cells Row E value VehCharac iVeh 4 shPOCscratch Cells Row F value num_traj_tot shPOCscratch Cells Row G
55. DP_inc and again evaluates each trajectory path for collisions this process continues until the end of the segment is reached For iSeg 1 To NOS For iDir 1 To 2 Step 2 For iLDS 1 To 2 Step 2 For iAlt 1 To num_Alts For iDP 0 To num_Departure_Incs If iDir 1 Then x0 iDP DP_inc iDir SegStart start at beginning of segment for primary direction C 81 Else x0 iDP DP_inc iDir SegEnd _ start at end of segment for opposing direction End If For itraj 1 To number of trajectories WF 1 num_traj_seg num_traj_seg 1 nopc number of path coordinate points initialize EFCCR for this trajectory EFCCRi num_traj_seg 1 0 Record Vehicle Type M C or T for this segment EFCCRi num_traj_seg 2 VehCharac iVeh 4 Record Alternative number for the segment EFCCRi num_traj_seg 3 iAlt Call ModulePOCanalysis sub_Impact_Search Next itraj Some additional variables are defined in this section of the program including POC num_traj_seg and EFCCR1i The variable POC represents the probability of collision and is applied as a weight factor to the crash cost of each collision As an example refer to the sequence of possible crash events illustrated in Figure 29 At the beginning of each trajectory path Point A the probability of occurrence is 1 0 In other words each trajectory case is an encroachment event so there is a 100 percent chance of an encroachment during the first inc
56. END TERMINAL oHx Longitudinal coordinates of hazard ft oHy Lateral coordinates of hazard ft oPDG Vertical grade percent oPDCR Horizontal curve radius in primary direction oPSL Posted speed limit mph DP_inc Increment of departure points along segment ft SegStart Longitudinal start point of segment ft SegEnd Longitudinal end point of segment ft oMedianHW Median half width ft hwyType Highway type divided undivided or one way NOS Total number of segments Program Variables Analysis Flag for conducting analysis for current roadside section Col_EFCCRi Column position on worksheet POC Scratch for analysis output count_pene Number of penetrations count_RR Number of rollovers after redirection from a hazard CSglob User defined X section o CSglob 1 y coordinate CSglob 2 z coordinate CSglob 3 Relative slope CSglob 4 Baseline probability of rollover as a function of slope CSglob 5 Probability of rollover adjustment factor for Grade o CSglob 6 Probability of rollover adjustment factor for horizontal curve O O O O CSloc User defined X section y z data in local coordinates d0 Distance from previous trajectory location to Hazard decel Deceleration of trajectory path C 62 EFCCR_RR Total of all EFCCRs for rollover after collision with hazard EFCCR_tot Total of all EFCCRs for each hazard EFCCRi Total of all EFCCRs for each trajectory computed for each segment grid_inc x i
57. Figure 23 The function and use of each of these settings buttons is described in detail in the Crash Prediction Module Chapter btnPrev_Click The lt X Section Info button sets the control back to the Cross Section worksheet Selecting the button executes this method which simply selects the Cross Section worksheet i e shXsection and set the value of frmRSAPcontrols mpControls value 4 RESULTS WORKSHEET The Results worksheet is used to display the results of the analysis to the user and in the background perform the benefit cost calculations Selecting the Results tab in the RSAP Controls Dialog or selecting the Results worksheet tab will set the frmRSAPcontrols mpControls Value property to 6 display the context sensitive buttons as shown in Figure 18 and activate the Results worksheet i e shResults C 38 The Results view of RSAP Controls shown in Figure 18 includes four command buttons which will be described below There is only one small user input area i e Range X5 X6 where the user can change the project life or rate of return RSAP uses the values entered previously on the Project Information worksheet as defaults but they are provided here as well in case the user desires to do some sensitivity analysis using just the life and rate of return M oe File Home Insert Page Layout Formulas Data Review View g Oo BRR J8 vg fe Feature Maintenance Cost x A B E D E F G H J
58. If loc_checkl gt oHx iAlt K 1 And loc_check2 lt oHx iAlt K 2 Then The first step of this task is to compute the lateral coordinate value of the line hazard at x and at x The collision flag is set to Collision checking When a collision has been determined this flag will then be set to true in which case rollover statistics will be computed prior to the analysis of the collision Hy0 HM iAlt K x oHx iAlt K 1 oHy iAlt K 1 Hyl HM iAlt K x dx oHx iAlt K 1 oHy iAlt K 1 Collision checking initialize collision flag The criteria for collision on the left side of the barrier is defined as follows If lateral trajectory at previous point is less than lateral position of hazard and the lateral trajectory at the current point is greater than lateral position of hazard and if there is no C 116 rollover or end of trajectory path then path crossed barrier from left side The width of the barrier is accounted for when determining the hazard location BHW barrier width 2 If yj lt Hy0 BHW _ And yj lt Application Max oHy oHy2 BHW _ And yj41 gt Hyl BHW _ And y gt Application Min oHy oHy2 BHW Then CSRL left collision side left used for determining sign of angle for redirection trajectories Collision true The criteria for collision on the right side of the barrier is defined as follows Jf lateral trajectory at previous point is
59. If yR iVeh i lt MinY Then MinY yR iVeh i j End If If yR iVeh i j gt MaxY Then MaxyY yR iVeh i j End If Ifj 1 Then MaxL yR iVeh i j 2 xR iVeh i j 2 0 5 Else MaxL MaxL yR yRj 1 xR xR 1 0 5 End If Next j Each selected trajectory path is assigned equal probability of occurrence Thus the probability of occurrence i e POC for a given trajectory path is computed as the probability that a redirection event occurred i e POR times the probability that the current path will occur i e number of paths POC POR 1 trajR_tot Set redirection flag to 1 to indicate that this is a redirection path This flag is used in ModulePOCanalysis to determine if various collision events will be considered e g rollovers are not considered for redirection trajectories since they were already accounted for in subroutine subPenetrate redir_flag 1 Call ModulePOCanalysis to Evaluate Path for Secondary Collisions The program calls ModulePOCanalysis to perform the collision analysis task where each trajectory is individually examined for possible collisions with hazards the collision statistics are computed and stored in the appropriate data collectors and these data are then returned to the main program i e ModulePOCmain for processing The programming details of ModulePOCMain were presented earlier Call sub_Impact_Search End If C 137 Move to next trajectory c
60. Median 2 0 00000 0 0000 0 0000 0 00000 0 00000 __ 0 0000 _ 0 0000 1 ijo L T 40 EdgeOfMedian 2 1 33781 17 4979 0 0000 0 0765 0 43745 0 03345 0 0000 17 4979 1 ijo L c 40 EdgeOfMedian 2 1 11484 17 4979 0 0000 0 0637 0 43745 0 02787 __0 0000 17 4979 1 iP R T 10 Rollover 3 0 00000 0 0000 0 0000 0 00000 0 00000 1 1P _ R c 10 Rollover 3 0 00000 0 0000 0 0000 0 00000 0 00000 1 afp L T 40 Rollover 3 0 00945 0 7805 0 0000 0 0121 0 01951 0 00024 1 ap c 40 Rollover 3 0 00788 0 7805 0 0000 0 0101 0 01951 0 00020 1 1Jo__ R T 10 Rollover 3 0 00000 0 0000 0 0000 0 00000 0 00000 1 1Jo__ R c 10 Rollover 3 0 00000 0 0000 0 0000 0 00000 0 00000 1 1jo L T 40 Rollover 3 0 00945 _0 7805 0 0000 0 0121 0 01951 0 00024 1 ijo L c 40 Rollover 3 0 00788 0 7805 0 0000 0 0101 0 01951 0 00020 1 2 P_ R T 10 EdgeOfMedian 1 0 00000 _ 0 0000 0 0000 0 00000 0 00000 0 0000 _ 0 0000 1 2 P_ R c 10 EdgeOfMedian 1 0 00000 _0 0000 0 0000 0 00000 0 00000 0 0000 _ 0 0000 1 2 Pp_ JL T 40 EdgeOfMedian 1 1 29183 15 7967 0 0000 0 0818 0 39492 0 03230 0 0000 15 7967 1 2 Pp_ L c 40 EdgeOfMedian 1 0 01131 0 1433 0 0000 0 0789 0 00358 0 00028 0 0000 0 1433 1 2o R T 10 EdgeOfMedian 1 0 00000 _ 0 0000 0 0000 0 00000 0 0000000 _0 0000 _ 0 0000 1 2o R c 10 EdgeOfMedian 1 0 00000 0 0000 0 0000 0 00000 0 00000 0 0000 0 0000 1 2o JL T 40 EdgeOfMedian 1 0 00000 0 0000 0 0000 0 00000 0 00000 0 0000 _ 0 0000 1 2jo L c
61. R SPEED ADJUST E a z z lt 2 HAZARD NAME cCosST 3 4 GenericBR L 0 0050 0 30 5 00 27 00 T BridgeRails 5 TL3FShapeBR L 100 0 0035 0 50 1 50 27 00 T BridgeRails 6 TL3NJShapeBR L 100 0 0035 0 50 2 00 27 00 T BridgeRails 7 TL3VertWallBR L 100 0 0085 0 50 0 50 27 00 T BridgeRails 8 TL4FShapeBR L 100 0 0035 0 20 1 50 32 00 T BridgeRails 9 TL4NJShapeBR L 100 0 0035 0 20 2 00 32 00 T BridgeRails 10 TL4VertWallBR L 100 0 0085 0 20 0 50 32 00 T BridgeRails 11 TL5FShapeBR L S 100 0 0035 0 10 1 50 42 00 T BridgeRails 12 TL5NJshapeBR L S 100 0 0035 0 10 2 00 42 00 T BridgeRails 13 TL5VertWallBR L 100 0 0085 0 10 0 50 42 00 T BridgeRails 14 GenericAttenuator P 0 0120 7 00 0 00 T CrashCushions_Gating 15 TL3HTCableGR L 100 00 800 0 0018 7 00 0 50 30 00 T Guardrails_Flexible 16 TL3LTCableGR L 100 00 800 0 0009 11 00 0 50 30 00 T Guardrails Flexible 17 TL3FShapeGR L 100 0 0035 0 50 1 50 27 00 T Guardrails_Rigid 18 TL3NJShapeGR L 100 0 0035 0 50 2 00 27 00 T Guardrails_Rigid 19 TL4FshapeGR L 100 0 0035 0 20 1 50 32 00 T Guardrails_Rigid 20 TL4NJshapeGR L 100 0 0035 0 20 2 00 32 00 T Guardrails_Rigid 21_TLSFshaneGR J Ss 100 0 0035 0 10 1 50 42 I Guardrails Rigid 4 M 4 gt h Severity Cross Section Encr Freq and Adj lt Results lt Profile lt Defaults Program Dail 4 t ri Figure 20 Seveity Worksheet Selecting the Hazar
62. Set the style of columns 7 and 8 to Normal Print the label Dia in column 7 Set the style of column 8 to Input2 Case TerminalEnds C 27 Set the style to of columns 4 to 6 to Normal 2 Set the value of columns 4 to 6 NA Set the style of columns 7 and amp to Normal Print the label Width in column 7 Set the style of column 8 to Input2 Set the default value to 24 End Case End Select RSAP Controls 3 pRovect 1 ALTS DEFINED IbIAItNum Value TRAFFIC Clear All btnClearAlts_Click Alternative Data btnCopyAlt_Click HEGHWAY pyAlt_Click Copy Alt 1 txtAlt2Copy Value btnDeleteAlt_Click txtAlt2Delete Value X SECTION btnSortAlts_Click ANALYZE a rbtnAlt1_Click SETTINGS rbtnAlt2_ Click btnAlt3_ Click HAZARDS rbtnAlt4_Click rbtnAlt5_Click tnViewHazData_Click btnPrevBuildSegments_Click tnNextAnalyze_Click Figure 11 RSAP Controls Dialog Alternatives C 28 IbIAItNum This is a text box label that displays the number of alternatives that have been defined by the user The initial default value is one The number of alternatives must be an integer greater than zero and less than 6 The user cannot change this text box RSAP changes the value based on the user choices described below btnClearAlts_ClickQ This button clears all user entered information from the Alternatives worksheet txtAlt2Copy The user can enter a number in this t
63. T OF TRAFFIC IN PRIMARY DIRECTION Enter a value PERCENT OF TRAFFIC ENCROACHING RIGHT between 0 HIGHWAY TYPE TERRAIN POSTED SPEED LIMIT USER ENROACHMENT ADJUSTMENT a il 52 80 00 ft Max Offset 200 00 ft ROAD SEGMENT DATA 9 9725 enhy 2 4931 2 4931 M 4 i Project Information lt Traffic Information Road Segments lt Alternatives lt Severi Cross Se 4 ___ m Ready ID 100 Oy Figure 7 Road Segments Worksheet Whole Roadway Characteristics Input Area Home Insert Page Layout Formulas Data fo Concrete Barrier Example Problem WHOLE ROADWAY CHARACTERISTICS PERCENT OF TRAFFIC IN PRIMARY DIRECTION PERCENT OF TRAFFIC ENCROACHING RIGHT Min Sta 0 00 ft HIGHWAY TYPE Max Sta 52 80 00 ft TERRAIN Max Offset 200 00 ft POSTED SPEED LIMIT USER ENROACHMENT ADJUSTMENT points mi RMBLSTRIP TRUE FALSE RT_SHLR_WIOTH ft M 4 h Project Information Traffic Information Road Segments Aktematives_ Severity Cross Secti 4 i seve CEEA Figure 8 Road Segments Worksheet User Entered Characteristics Input Area C 22 The Expected Encroachments Table has a variety of formulae coded into the worksheet as described below The descriptions below apply to rows 14 through 33 where ROW would be replaced by the particular row number Column Formula A IF D64 gt ROW 13 ROW 13 F IF D ROW gt
64. TRL S This is the macro that actually starts RSAP CONCLUSIONS The preceding chapters and sections have described the architecture of RSAPv3 it event control structure and user input facilities The algorithms used for the analysis were presented with pseudo code and flow charts This manual should provide all that is necessary for a programmer needing to modify update or otherwise revise RSAPv3 C 152 REFERENCES Bligh04 FHWA91 Mak10 Bligh R P Shaw Pin Miaou and King K Mak Recovery Area Distance Relationships for Highway Roadside National Cooperative Highway Research Program Project 17 11 Washington DC 2004 Supplemental Information for Use with the ROADSIDE Computer Program Federal Highway Administration Washington DC August 1991 Mak K K Sicking D L and B A Coon Identification of Vehicular Impact Conditions Associated with Serious Ran off Road Crashes National Cooperative Highway Research Program Report 665 Transportation Research Board Washington D C 2010 C 153
65. These six buttons are briefly described below shPrjlnfo RSAP Controls J Dire shTraffInfo eperra hRdS Traffic Information aa Road seamen shAlternatives ae shXsection Alternatives Cross Section xsection shResults Results shSeverity Severity Contents of this area depend on the tab SETTINGS ill ter a proje btnEngMan_Click btnRSAPhep_Click btnUserMan_Click tt G a lt a 6 2 IbINextStepHint Caption Help btnSave_Click Save btnSaveAs_Click btnExit_Click cM Figure 2 RSAP Controls Dialog tab and button bindings C 12 selected User s Manual btnUserMan_Click This button displays a PDF copy of the User s Manual RSAP first looks for the User s Manual file 1 e RSAPv3userManual pdf in C Program Files RSAPv3 If it does not find the file there it looks in the RSAP home directory stored in the Program Information worksheet in cell B24 If the file is not found in either of these places RSAP attempts to load the file from the Internet at http rsap roadsafellc com RSAPv3userManual pdf If even this fails an error message is displayed Regardless of the file location the file is displayed using the ActiveWorkbook FollowHyperlink method both local files and internet files are displayed using the same method btnEngMan_Click This button displays a PDF copy of the Engineer s Manual and the code is identical to
66. Turn off the formula bar Protect shSeverity Protect shPrgData Hide shPrgData Hide the Excel ribbons interface Re start RSAP by calling moduleTools StartRSAP Exit turn on the ribbon interface and unprotect the worksheet to allow edits Turn on display headings Turn on the formula bar Unprotect shSeverity Unprotect shPrgData Unhide shPrgData Unhide the Excel ribbons interface Exit C 49 End if ENCROACHMENT MODULE As discussed earlier the number of encroachments that can be expected on a particular road section in a year is given by encr n ADT L P Encr L f pase EAF i 1 where the terms are as defined earlier The encroachment module of RSAPv3 is executed when the user presses the Segment Project button on the Highway tab of the RSAP controls dialog shown earlier in Figure 9 The code for the encroachment module is contained in module Encroachments which contains five subroutines and functions PROCEDURE Estimating the number of encroachments is initiated in one of two ways by the user either selecting the Segment Project button or the Recalculate Encroachments buttons on the RSAP controls dialog as shown in Figure 9 Selecting either button results in the following moduleEncroachments calcBaseEncr moduleEncrochments adjustEncr RSAP first calculates the expected number of encroachments using the base conditions i e no adjustments and then finds the appropriate adju
67. USE Mid Life 6 MID LIFE ADT vehicles day 7_ END OF LIFE ADT vehicles day 8 ADT USED BY RSAP vehicles day 9 10 VEHICLE MIX Trajecton Trajectory Information RSAP VEHICLES 11 12 13 Motorcycles 0 56 TrajectoryGrid1 14 Passenger Vehicles 2 3 85 0 3 400 TrajectoryGrid2 RedirectionCars 15 Trucks 4 13 15 0 T 50 000 TrajectoryGrid3 RedirectionTrucks 16 17 18 19 20 21 22 23 24 25 26 Total 100 00 27 Click here for the on line link to the FHWA classification system E Maw Project Information Traffic Information lt Road Segments Alternatives lt Severity lt Cross Section Endi 4 rf Ready Average 1 69 Count 3 Sum 5 08 _ EB 0 Gi 100 g OR Figure 5 Traffic Information Worksheet C 19 Change Method Whenever a value on the Traffic Information worksheet is changed this method is activated It simply checks to see if shTraffInfo Range C3 C4 has a value using moduleTools RangeIsMT subroutine If C3C4 has values the Highway Info gt button is made visible If there is no value the Highway Info gt button is hidden btnClearTraffInfo_ClickQ Selecting the Clear User Information on this form executes this method which is active only on the Traffic Information worksheet The user is asked if the really want to delete all the traffic information if they respond YES then all the yellow INPUT cells are cleared of their content The Highway Info gt n
68. _2 true End If Elself hazard type Line Then C 110 If both ends of the hazard are less than the minimum lateral extents of trajectory _ Or _ if both ends of the hazard exceed the maximum lateral extents of trajectory Or if hazard is Opposing median edge And encroachment is from Primary Direction _ Or_ if hazard is Primary median edge And encroachment is from Opposing Direction _ Then logic_I K false Else logic_I K true logic_2 true End If End If Next K Evaluate Trajectory Path This section of the module checks for impacts when the following three conditions are met 1 the hazard is within the lateral extents of the trajectory path or terrain rollover is possible 2 the velocity is greater than zero and 3 the probability of occurrence is greater than 0 1 The program examines each point of the trajectory path starting at xo which is the current encroachment location being evaluated for all the trajectory paths as illustrated in Figure 37 Starting station Ending station of segment of segment Increment of SegStart SegEnd departure points k Segment engi along segment SegLength DP_inc K Current departure point Departure increment iDP 01 2 34 5 Xo DP DP_inc iDir SegStart 5 RANAR oHx oHy Hazard 0Hx gt 0Hy gt Figure 37 Illustration of roadway segment showing definition of xo C 111 The following lines of code perform the following tasks
69. a median along a specific section of a divided highway where the roadside in both the primary and opposing directions are to remain unchanged For each new roadway segment and traffic direction the program will read from the RSAPv3 Control Form to determine which roadsides to analyze refer to Figure 23Error Reference source not found In the following lines of the program iDir 1 corresponds to the primary direction of traffic and iDir 1 represents opposing traffic direction Likewise iLDS 1 corresponds to right side encroachments and iLDS 1 corresponds to left side encroachments For iSeg 1 To NOS For iDir 1 To 2 Step 2 For iLDS 1 To 2 Step 2 Primary Right Encroachments If iDir 1 And iLDS 1 Then C 72 If check box for primary right False Then skip analysis Primary Left Encroachments Elself iDir 1 And iLDS 1 Then If check box for primary left False Then skip analysis Opposing Right Encroachments ElseIf iDir 1 And iLDS 1 Then If check box for opposing right False Then skip analysis Opposing Left Encroachments ElseIf iDir 1 And iLDS 1 Then If check box for opposing left False Then skip analysis Else Continue with analysis for the current encroachment side End If Define Roadway and Roadside Characteristics For each alternative the program 1 reads in specific roadway characteristics posted speed limit highway grade and horizontal curve radius 2 reads in
70. al to lateral position of hazard at current increment and is greater than lateral position at next increment then collision occurs with left side of hazard Initialize Rollover Variables Determine Impact Side Traffic or Non Traffic Side Else If Y gt Ynazara aNd Yje1 lt Yhazard Then Collision TRUE if lateral extent of trajectory is greater than or equal to lateral position of hazard at current increment and is less than lateral position at next increment then collision occurs with right side of hazard Compute Impact Angle Determine Probability of Penetration Call subPenetrate Evaluate Redirection Paths Call subRedirect Figure 36 Flow chart for detecting collisions with point hazards in Module POCanalysis C 109 Initialize Variables Several variables are initialized at the beginning of this analysis procedure end_pen_flag 0 VE VO v VO decel decel0 For K 1 To total number of hazards for current alternative d0 K distance from current path position to first hazard coord Next K The variable end_pen_flag is initialized to zero which indicates that the path is not a redirection path and that terrain rollovers should be considered i e rollovers after redirection are handled separately The variables VE and v are defined as the initial velocity the variable decel is defined as the average deceleration of th
71. and median cross sections for each of the alternatives defined on the Alternative worksheet as shown in Figure 12 The rose colored cells may be changed by the user but contain RSAP default values Home Inset Page layout Formulas Data Review D5 f 2 1 right X SECTION FOR ALTERNATIVE DEFAULT X SECTION All Flat All Flat AllFlat All Flat 25 0 SEG START STA END STA 2 2 3 4 5 an 1 0 00 52 80 00 2 1right 4 1 right 2 1 right s0 j t 100 0 50 0 5 000 so H 4 15 0 i 250 t Name I T 4 SEGMENT CHARACTERISTICS Total Lanes 4 Number Lanes Prim 2 Lane Width ft 12 0 Left Shoulders ft 10 0 Right Shoulders ft 6 0 Median Width ft 27 0 Curb Height c 0 0 Slope Hav v 2 H 1v Offset 123 5 123 5 223 5 Elev 13 5 135 63 5 Marw Traffic Information Road Segments Akematives Severity Cross Section lt Enc Freq and Adj Resuks Ready 3D 100 C Figure 12 Cross Section Worksheet Selecting the X Section tab in the RSAP Controls Dialog or selecting the Cross Section worksheet tab will set the frmRSAPcontrols mpControls Value property to 4 display the context sensitive buttons as shown in Figure 13and activate the Cross Section worksheet i e shXsection
72. ard severity and impact conditions EFCCR VehCharac10 oHzrd_EFCCR65 274625 v 60 88 3 The EFCCR value is a normalized crash cost defined as the ratio of the crash cost divided by the cost of a fatal crash The EFCCR is weighted based on the probability of the collision occurring i e POC The value for POC is determined in subPenetrate and C 124 subRollover based on probability of penetration and rollover respectively The cumulative crash cost for the current hazard and the total number of impacts on the hazard are then computed This information is later used to compute the average crash cost for impacts with the hazard EFCCR_tot EFCCR_tot EFCCR POC impact_Count_tot impact_Count_tot POC The following information is not used in computing crash costs but is computed here and later written to the RSAPv3 POC scratch worksheet for information purposes only If CS TS Then impact_Count_TS impact_Count_TS POC Else impact_Count_NTS impact_Count_NTS POC End If End Sub SubPenetrate This subroutine is called by ModulePOCAnalysis to determine the probability of penetration of a hazard during collision The basic procedure is to 1 determine probability of penetration due to structural failure or vaulting of hazard 2 determine probability of penetration due to rolling over the barrier i e analysis for trucks only 3 determine probability of rollover after redirection and compute cras
73. ase yy lateral coordinate of resampled cross section profile from trajectory database C 95 e zz vertical coordinate of resampled cross section profile from trajectory database Read all Data from Trajectory Grid Worksheet The number of rows of data in the trajectory database is determined and the variable array traj_select is re dimensioned The name of the trajectory database is passed in from Module POCMain as SheetName The program then reads in the complete trajectory database and stores it in the array variable TrajectoryData to facilitate quick access to the data Count 0 Do Until a blank row is found indicating the end of data Count Count 1 Loop ReDim traj_select Count TrajectoryData Sheets SheetName Range Cells 4 A Address Cells Count 3 num_pre iVeh 300 Address value Compute Roadside Cross Section Profile Score In order to perform a point to point comparison of the similarity of a given roadside cross section to those from the trajectory database the lateral coordinates must be sampled at the same increments The program first resamples the cross section coordinates for the project segment at lateral increments of delta_y using linear interpolation delta_y 1 ft y 0 CSloc 1 1 z 0 CSloc 1 2 i 2 For j 1 To ymaxp delta_y y y j 1 delta_y If y j gt CSloc i 1 Then if y gt y0 then a slope change occurs between these two positions 2 j CSloc i 1 3 yj
74. ase in the database and repeat analysis procedure MyrowR MyrowR I next redirection trajectory Loop End Sub SubRolloverM2a This module is called by ModulePOCanalysis to update the variables in the rollover algorithm at each increment of the trajectory path The probability of rollover at each increment is a function of the incremental length of the trajectory L The general procedure is as follows At each increment the program 1 determines the probability of rollover for the current increment i e P R slope Psa Ps uc 2 updates the effective probability of rollover for the trajectory path and 3 updates the average velocity cubed at each increment for use later in subroutine SubRoloverM2b for computing rollover costs The flow chart for this program module is shown in Figure 42 C 138 subRolloverM2a Determine baseline rollover statistics for current path increment on current roadside slope Update cumulative Update the cumulative probability of rollover sum of the average N velocity cubed De P R slope a Psc s Ps uc i Li gt v3 7 avg Return to POCmain Figure 42 Flow chart for subroutine subrolloverM2a C 139 Input Variables The following are a list of variables passed from the parent module and used in this subroutine e CountCSg number of coordinates in global cross section profile e CSglob 1 y coordinate value of global cross section profile e CSglob 2 z coordinate valu
75. at will turn on debugging messages that may be useful to a programmer debugging the procedures Procedure All the encroachment adjustment factors are located on shEncrAdj so the first step is to select that worksheet shEncrAdj Range startCell select Do Until lookUpVal gt selection and lookUpValue lt selection off next Row Selection offset nextRow select Loop If selection value Else dd 99 then notify user an adjustment could not be found A selection Bz selection offset 1 0 C selection offset 0 shft D selection offset 1 shft E lookUpVal Adjustment C D C E A B A End if Return Adjustment In setting up the lookup tables on shEncrAdj it is important to be sure that the first and last rows of the first column have values that are sized such that the input value is within the range Using the Lane Width example the smallest lane width in the table is 0 and the largest is 40 Obviously these are not reasonable values but they are used so that if a value of say 8 9 is entered the value will not fall below the first value in the table Likewise a maximum value should be identified such that there will never be an input value larger than that value If a 14 ft lane is entered the value is still in the range of the table and the interpolation will work correctly C 51 adjustEncr After the base encroachment frequency has been determined in calcBaseEncr it is modified by any appropriate adjustment factors ba
76. ation Number of alternatives Num_Alt Number of hazards associated with each alternative oNum_Hazards Hazard Type oHzrd_Type Hazard name oHzrd_Name General Type of Hazard oHzrd_GenType The EFCCR65 for the hazard 0oHzrd_EFCCR65 C 65 e The percent penetration rollover vault for the hazard oHzrd_Prcnt_PRV derived from crash data e The percent rollovers after redirection from the hazard oHzrd_Prcnt_RR derived from crash data e The structural capacity of the hazard oHzrd_Capacity in units of ft lb e The height of the hazard oHzrd_Height for longitudinal barriers e The longitudinal barrier that an end terminal is attached to 0oHzrd_Connection e The longitudinal coordinate of the nearest upstream point of the hazard oHx e The lateral coordinate of the nearest upstream point of the hazard oHy e The slope of the line defining line hazards HM e Radius of point hazards R Lookup Tables for Probability of Terrain Rollover The probability of rollover is computed in RSAPv3 based on sideslope horizontal curve radius and highway grade The data which RSAPv3 uses for computing the probability of rollover were adopted from the NCHRP 17 11 study conducted by Bligh Miaou and Mak Bligh04 and from the FHWA supplement to the Roadside Design Guide FHWA91 More detail on the development of the rollover model is discussed in the ENGINEER S MANUAL There are currently three lookup tables in RSAPv3 related
77. ay data is offset 3 All others return an error Select Case UCase hwyType Case U Col 1 Case D C 53 Col 2 Case O Col 3 If Not shRdSegs Range E3 value 100 Then make sure 100 of volume is in primary direction for one way Userchoice gt tell user RSAP is changine the primary vol to 100 If userchoice vbOK Then shRdSegs Range E3 value 100 Else Exit Sub End If End If Case Else MsgBox Error illegal highway type Exit Sub End Select Primary Direction Grade Adjustment p_gradeAdj adjust shEncrAdj AG5 1 p_grade debugFlag Primary Direction Horizontal Curve Adjustment p_hcurvAdj adjust shEncrAdj AK5 1 p_hcurv debugFlag Speed Limit Adjustment spdLimAdj adjust shEncrAdj Q5 Col spdLim debugFlag Lane Width Adjustment InWidthAdj adjust shEncrAdj U5 Col Inwidth debugFlag If numLanePrim gt numLane And numLane gt 1 Then MsgBox Number of lanes in the primary direction on amp vbCrLf amp _ segment amp CStr seg amp cannot be equal to or greater than the amp vbCrLf amp _ total number of lanes Dividing lanes amp vbCrLf amp _ equally between directions numLanePrim numLane 2 End If Number of Lanes Adjustment for primary direction p_numLaneAdj adjust shEncrAdj M5 Col numLanePrim debugFlag find the adjustments for the opposing directions but only if not a one way highway C 54 If Not hwyType O Then
78. bability of rollover since last collision Proll2 SumPRslopext LT Proll Compute probability of rollover along current path segment POCroll Proll2 POC 1 POCroll0 Compute collision cost Call subCollision_Statistics Compute probability that vehicle continues without rolling over Re initialize rollover variables POCroll0 and ProllO Return to POCmain Figure 43 Flow chart for subroutine subRolloverM2b Input Variables The following are a list of variables passed from the parent module and used in this subroutine e CS collision side i e traffic or non traffic side e Haznum total number of defined hazards e LT total length of trajectory path computed from Trajectory Grid in ModulePOCtraj e POCroll0 Effective probability of rollover at time of previous collision event C 142 e POC probability of occurrence e SumPRslopexL cummulative sum of P RICSslope Lj e Proll0 Probability of rollover before previous event e g if no prior collision occurred for this trajectory path then Proll0 0 e V3avg average cubed velocity Program Variables The following are a list of variables defined in the subroutine e K hazard number e POCroll Effective probability of rollover used in crash cost calculations i e probability of rollover given roadside and impact conditions times the probability of the trajectory getting to this point e Proll2 Probability of rollover since previous event e Vavg Ef
79. characteristics that is the program selects all trajectory cases that have characteristics which fall within a specified range of those defined for a given segment of roadway Refer to the ENGINEER S MANUAL for more information regarding trajectory selection methodology The program calls ModulePOCtraj to gather trajectory information which will be used in the analysis such as number of trajectory cases num_traj coordinates of the trajectory path trajx and trajy the number of data columns preceding the trajectory path information num_pre the longitudinal increments of the path data grid inc the minimum and maximum lateral extents of each trajectory path MinY and MaxY and the maximum length of each trajectory path MaxL Call ModuleP OCtraj TrajectorySelect Initialize Variables for Collision Statistics During the analysis various types of data relevant to the probability of collision are collected These data include number of traffic side impacts on each hazard number C 80 of non traffic side impacts on each hazard total number of all impacts on each hazard total crash cost EFCCR for collisions with each hazard total crash cost associated with rollovers after redirection with each hazard number of rollovers after redirection and number of penetrations of each hazard These data are stored until the current roadside encroachment location has been analyzed for the full length of the segment for the current vehicle type
80. cs for Collision with Hazard The program first determines which side of the hazard was struck which is stored in the variable CS y traj iVeh i j num_pre y0 lateral impact location Call sub_CS oHy iAlt K 1 oHy iAlt K 2 iDir CS y0 y A median edge line is considered to be a hazard only when a vehicle is crossing into opposing lanes of traffic So if the hazard is not a median edge and the vehicle is not crossing from the non traffic side then it is considered a collision and the subroutine subCollision_Statistics is called to compute the crash cost statistics The subroutines are presented in a later section of this Manual and the details of computing crash statistics are presented in the ENGINEER S MANUAL If Not oHzrd_Name iAlt K EdgeOfMedian And CS NTS Call subCollision_Statistics The initial velocity for subsequent redirection trajectories is equal to the current velocity The angle of impact relative to the barrier is also computed for use in computing impact severity and redirection paths vRO v impact velocity stored for use in evaluating redirection paths in subRedirect Impact angle with respect to roadway If dx 0 Then Theta_traj Atn y x Else Theta_traj Atn y yj dx End If Angle of hazard with respect to roadway Theta_Haz Atn HM iAlt K Impact angle with respect to hazard Theta Theta_traj Theta_Haz Impact angle w r t barrier 3 Dete
81. d tab in the RSAP Controls Dialog or selecting the Severity worksheet tab will set the frmRSAPcontrols mpControls Value property to 8 display the context sensitive buttons as shown in Figure 21 and activate the Severity worksheet i e shSeverity Activate Method Selecting the Hazard tab on the RSAP Dialog Controls or the Severity Excel worksheet tab instantiates the shSeverity Worksheet_Activate method In the case of shSeverity RSAP simply sets frmRSAPcontrols mpControls value 8 and positions the view at the row 1 column 1 Five command buttons are available in the Hazards area as shown in Figure 21 There is also a hidden key stroke macro moduleTools editSeverities which can be used to edit the worksheet as described in the Engineer s Manual These macros will be described below C 46 RSAP Controls btnAlpha_Click btnCategory_Click btnSeverity_Click btnCapacity_Click btnBk2AltsClick Figure 21 RSAP Controls Dialog Hazards btnAlpha_Click This button like the following three buttons simply rearranges the hazard data base shown in the Severity worksheet In this case the hazards are arranged in alphabetical order by the hazard name listed in column A The method uses the following VBA Excel sort method C 47 first find the bottom row Count 4 Do Until shSeverity Cells Count 1 Count Count 1 Loop botRow Count 1 sort t
82. d Selecting the Alternatives tab on the RSAP Dialog Controls or the Alternatives tab in the Excel worksheet tabs instantiates the Alternatives Worksheet_Activate method The value of mpControls is set to 3 and Alternative number 1 is pre selected for input by executing the macro moduleAlternatives EditAlt 1 Change Method Whenever a value on the Alternatives worksheet is changed this method is activated The shAlternatives Change method performs a great deal of formatting for all rows greater than 9 First event handling is disabled during the execution of the macro and then the following set of case statements are executed to accomplish the formatting Select Case Target Column Case 1 12 23 34 45 columns containing the hazard type value Clear the eight columns to the left of the selected cell Select Case Hazard Type Case any longitudinal barrier hazard type Set the style to of columns 4 to 6 to Input Set the style of columns 7 and 8 to Normal Clear any values from columns 7 and 8 Print the label width in column 7 Set the style of column 8 to Input2 Case Special Edge Set the style to of columns 4 to 6 to Input Set the style of columns 7 and 8 to Normal Clear any values from columns 7 and 8 Print the label NA in column 7 Set the style of column 8 to Input2 Case PoleTreeSign Set the style to of columns 4 to 6 to Normal 2 Set the value of columns 4 to 6 NA
83. d to END TERMINAL oHzrd_EFCCR65 hazard severity Effective Fatal Crash Cost Ratio for impact speed of 65 mph oHzrd_Height height of hazard ft oHzrd_Name hazard name e g TL3FShapeBR oHzrd_Prcent_PRVR percent of penetration vault from crash statistics oHzrd_Prent_RR percent of rollover after redirection from crash statistics oHzrd_Type hazard type oHx longitudinal coordinate of hazard with respect to global reference frame oHy lateral coordinate of hazard with respect to global reference frame C 133 e HM slope of hazard with respect to global reference frame e num_traj_seg cumulative number of trajectories for this segment e R radius of hazard Procedure First the new array variables which will be defined in these calculations are dimensioned Dim xR 13 100 500 Dim yR 13 100 500 Dim thetaR 2 Dim dOR ReDim dOR total number of hazards including rollover Redirection Speed When vehicles impact against longitudinal barriers some of the kinetic energy is expended through various mechanisms The result is a reduced velocity of the vehicle as it redirects from the barrier system It is not possible to accurately calculate the exact reduction in kinetic energy of the vehicle without conducting a detailed analysis of the crash event e g finite element analysis It was determined from review of full scale crash tests that the typical loss of kinetic energy could be approximated by multiplying the impact en
84. d updates to the probability of rollover data which can be made directly to the worksheet without any modifications needed in the program For example not only can the values in the table be easily changed but also the number of rows and columns of data can be easily expanded or reduced as well It is important that that the names of these table headings are not changed however since the program uses these names to identify the appropriate table on the worksheet Table 2 Adjustment Factor Lookup Table for probability of rollover as a function of roadside slope and vertical grade AQ AR AS AT AU AV Slope Grade Adjustment Vertical Grade C 67 Table 3 Adjustment Factor Lookup Table for probability of rollover as a function of roadside slope and horizontal curve radius AW AX AY AZ BA BB BC Horizontal Curvature 1 R Adjustment The program reads the adjustment factor tables for vertical grade and horizontal curve using the same procedure that was used to read the table of baseline probability for rollover discussed above The name of the table headings for the vertical grade adjustment factors and the horizontal curve adjustment factors are named Slope Grade Adjustment and Slope Horizontal Curvature 1 R Adjustment respectively The routine subRollInput is used to locate and read in the adjustment factor tables which will be used later in the analysis As mentioned previously the adjustment table data can be
85. e hazard 3 determine probability of penetration and 4 continue evaluating current path post penetration for secondary collisions 1 Compute Rollover Statistics and Cost If the trajectory is not a redirection trajectory then the program calls subroutine subRolloverM2b to calculate rollover statistics If redir_flag lt gt 1 Then Call subRolloverM2b Initialize Rollover Variables SumV2 0 V2avg 0 N 0 End If 2 Compute Crash Statistics for Collision with Hazard All collisions with point hazards are considered traffic side impacts so the program sets CS TS The subroutine subCollision_Statistics is called to compute the crash cost statistics Call subCollision_Statistics 3 Determine Probability of Penetration The subroutine subPenetrate is called to compute the probability of penetration due to exceeding structural capacity of the hazard Call subPenetrate If the hazard is an end treatment for a LON barrier then set end_pen_flag value to the hazard number corresponding to the mating LON barrier and ignore subsequent impacts on that barrier If oHzrd_GenType iAlt K TerminalEnds Then end_pen_flag oHzrd_Connection iAlt K End If Along with the crash statistics e g probability of penetration the subroutine subPenetrate also passes back the updated velocity which is reduced according to the amount of energy expended in penetrating the hazard The initial velocity for post C 122
86. e B71 C90 G71 V90 is cleared to prepare it for new data Procedure The purpose of the macro is to sort the characteristics of the roadway into order of increasing station number in the primary direction The sort first sorts by start station C 57 and then by end station This sometimes takes several iterations until the list is contiguous i e the end station of one segment is the same as the start station of the next The macro will split over lapping characteristic definitions and fill in missing segments If any row has a start station that is greater than the end station the row is deleted and the user is notified Negative stations are allowed If shRdSegs range A98 is blank then Notify the user there are not segment characteristics Exit the sub Else Do Until the Begin Station value is blank If End Station lt Begin Station then Notify the user Ask if this row should be deleted If User says NO then Exit Sub Else Copy the range from the next row to the last Paste the copied range over the active row Increment the row End if Loop allOK FALSE allOK is a flag indicating a problem has been found CheckNo 0 checkNo is an interation counter maxChecks 10 maxChecks is the maximum no of iterations Do While allOK FALSE and CheckNo lt maxChecks Sort shRdSegs Range A98 D587 by Begin Station and End Station If Begin and End stations of this row are the same as the next then The characteristics are on the same seg
87. e frame to the local reference frame C 74 The following section of the program performs the task of reading the roadside cross section coordinates corresponding to the current encroachment location and converting them from global coordinates to the local reference frame of the trajectory database For iSeg 1 To NOS For iDir 1 To 2 Step 2 For iLDS 1 To 2 Step 2 For iAlt 1 To num_Alts The following lines of code define the location i e starting row and column position of the cross section data on the RSAPv3 worksheet named Profile corresponding the current roadside encroachment location e g PR PL OR or OL and reads in the cross section coordinates SegOffset row position on worksheet Alternative AltOffset column offset on worksheet Alternative based on alternative num Shift column offset on worksheet Alternative based on encroachment side For i 1 To 8 If data exists in cell iSeg Altoffset shift 2 i 1 lt gt Then iXsect iXsect 1 count number of x section data points CSloc iXsect 1 lateral coordinate of X section CSloc iXsect 2 vertical coordinate of X section End If Next i The next step is to transform the cross section coordinates from the global to local coordinates This task is generally carried out via the coordinate transformation matrix however since the angle between the global and local reference frames will always be either 0 or 180 deg
88. e of global cross section profile e CSglob 3 slope of global cross section e CSglob 4 baseline probability of rollover e CSglob 5 vertical grade adjustment factor for rollover e CSglob 6 horizontal curve radius adjustment factor for rollover Program Variables The following are a list of variables defined in the subroutine e Lj length of trajectory increment e POR probability of rollover e SumPRslopexL cummulative sum of P RICSslope Lj e SumV3 cumulative sum of cubed velocities e V3avg average cubed velocity Procedure Initialize probability of rollover to a value of zero POR 0 initialize Probability to 0 The baseline probability of rollover POR is determined by associating the location of the current increment with the probability of rollover statistics in the array variable CSglob i Do While POR 0 And i lt CountCSg If y lt CSglob i 1 Then POR CSglob i 4 CSglob i 5 CSglob i 6 i itl Loop The next step is to update the effective probability of rollover for the trajectory path which is computed as the cumulative sum of the probability of rollover at each increment SumPRslopexL SumPRslopexL POR Lj The following lines of code update the average cubed velocity at each increment for use in later in subroutine SubRoloverM2b for computing rollover costs SumV3 SumV3 v 3 V3avg SumV3 N C 140 End Sub SubRolloverM2b This subroutine is called by ModulePOCanalysis to co
89. e the formatting is complete event handling is re enabled the sheet is re protected and cell D5 is initially selected Change Method Whenever a value on the Cross Section worksheet is changed the shXsection Change method is activated As usual event handling is disabled and the sheet is unprotected Tf the user selects a cells in the range D5 H24 do this If 4 gt Target Row lt 25 and the 3 gt Target Column lt 9 then Copy segment information from shRdSegs Write it into cells D26 D31 End if Event handling is then re enabled and the sheet is re protected and controls is passed back to the user Initially Hidden Buttons RSAP Controls lbtnSaveXsection_Click IbIEditXsection Caption btnDeleteXsection_Click IbXsectionNames btnPrevBuildSegments_Click btnNextAnalyze_Click Figure 13 RSAP Controls Dialog Cross Section btnDefaultXsection_Click This macro copies the default cross sections defined on the Alternative worksheet to all segments listed for that alternative The individual segments for each alternative can be further modified by selecting the Assign button The procedure is as follows Unprotect shXsection Disable Event Processing C 32 alts Read the number of alternatives from shAlternatives Range C3 hwyType Read the highway type from shRdSegs Range E5 segs Read the number of segments from sRdSegs Range D64 For iSegs 1 to segs For iAlt 1 to alts Copy the name in row3
90. e trajectory path The variables v and decel may change during the analysis depending on various factors and therefore must be renamed at the start of the analysis to prevent any changes from being passed back to the parent module Determine if Trajectory Path Falls Within Extents of the Hazard The next step in the analysis is to determine if a hazard is located within the lateral extents of the trajectory path If it is not then it will not be checked for impact with the hazard If the hazard is located outside the extents of the trajectory path then a flag is set logic_l k false which tells the program that it can skip the collision analysis for hazard k If the hazard is located within the extents of the trajectory path then the program sets logic_I k true which tells the program that it must check that trajectory for impact with hazard k It also sets another flag logic_2 true which tells the program that at least one hazard is located within the extents of the trajectory path The probability of roadside rollovers is checked for all cases unless it is a redirection trajectory max_extent maximum lateral extent of trajectory path min_extent minimum lateral extent of trajectory path For K 1 To total number of hazards for current alternative If hazard type Point Then If oHy iAlt K 1 lt min_extent Or oHy iAlt K 1 gt max_extent Then Logic_1 K false Else Logic_1 K true logic
91. ect is Station 3 45 67 This is only a display format meaning the number is entered into the cell as 345 67 but will be displayed as 3 45 67 All cells that indicate station input have validation rules attached such that if the sign or any other non numeric character is typed an error will be displayed Most cells that accept user input i e cell styles Input and Input2 have validation rules attached to prevent invalid data from being entered For example if a positive numeric value is needed a validation rule requires the cell field to be input as such The many validation rules are not described herein but they can easily be identified by selecting cell of interest going to Data gt Data Validation gt Data Validation and examining the rule appropriate for that particular cell PROGRAM INITIATION RSAPv3 is started whenever an RSAP macro enabled worksheet or template is started in MS Excel and involves three subroutines found in moduleTools e AutoOpen e StartRSAP e ProcessPrioritySet The subroutine moduleTools AutoOpen automatically starts when an RSAP workbook is opened This subroutine does the following e Unload any open forms so they do not conflict with the new instance of RSAPv3 e Hide the standard excel ribbons interface and set up the standard RSAPv3 view e frmRSAPsplash displays the opening splash screen for 5 seconds e moduleTools StartRSAP starts the RSAP program The subroutine moduleTools S
92. ents corresponds to a roadway curving to the right for traffic moving in the Primary traffic direction Thus when a vehicle traveling in the primary direction encroaches to the right the road curves back toward the encroachment path as the vehicle advances Such encroachments tend to remain relatively close to the roadway On the other hand when a vehicle traveling in the primary direction encroaches to the left the roadway curves away from the encroachment path These encroachments tend to extend farther and farther from the roadway as the trajectory advances Similar situations exist C 73 for vehicles traveling in the opposing direction The following lines of code read in values for the roadway characteristics from the worksheet Road Segments and redefine them according to the current encroachment conditions oPSL posted speed limit read from worksheet Road Segments oPDG vertical grade iDir oPDCR horizontal curve radius iDir iLDS Roadside Cross Section Geometry for Use in Trajectory Selection The trajectory cases in the crash reconstruction database are all normalized to correspond to primary right departures That is the cross section coordinates in the crash reconstruction database are based on a local reference frame relative to the departure point which starts at lateral offset y 0 and extends from that point with lateral coordinate values increasing monotonically An important criterion used in the se
93. er Hazname selection offset 0 5 the hazard name Vehicle selection offset 0 3 the vehicle type numEncr selection offset 0 4 number of encroachments encrlType selection offset 0 1 amp selection offset 0 2 read the number of expected encroachments for each encr type Select Case encrType Case PR Encr shRdSegs cells 13 seg G Case PL Encr shRdSegs cells 13 seg H Case OR Encr shRdSegs cells 13 seg I Case OR Encr shRdSegs cells 13 seg J Case Else gt Error message End Select Find the vehicle cost adjustment and traffic mix I 14 Do Until shTraffInfo cells I 4 value If shTraffInfo cells I 4 value vehicle then look for a match vehicleMix shTraffInfo cells I 3 Exit Do End If C 147 I 1 Loop Read in the number of events for the row Num_crashes selection offset 0 8 selection offset 0 9 crashes Num_prv selecton offset 0 14 penetrations rolls vaults Num_reroll selection offset 0 15 redirection rollovers If numEncr gt 0 then Estimate the total number of crashes and the crash cost If Num_crashes is not 0 or blank then Totalcrash Num_crashes encr NumEncr vehicleMix Crashcost vsl selection offset 0 12 encr vehicleMix Else Totalcrash 0 Crashcost 0 End if Estimate the Penetration Rollover Vault crashes If Num_prv is not 0 or blank then Prv_crash Num_prv encr NumEncr vehicleMix Else Prv_crash 0 End if Esti
94. ergy by the sine of the impact angle m vehicle weight 32 2 lb ft s2 vehicle mass KE 1 2 m v 2 kinetic energy computed from impact velocity DeltaKE KE Sin Abs Theta change in energy during redirection from hazard vRO 2 m KE DeltaKE 0 5 redirection velocity Select Redirection Paths Determine Name of Worksheet with Redirection Trajectories The redirection trajectory paths are selected based on vehicle type and barrier type and are obtained directly from the predefined paths on the RSAPv3 worksheets redirection worksheet containing redirection trajectories based on vehicle type The direction of the local x coordinate for the redirection trajectories is initialized to be in the same direction as the impact trajectory grid_incR Sheets redirection Cells 2 E value grid_inc Abs grid_inc Max_Traj_xR 300 Max trajectory length on Redirection Grid C 134 nopcR Max_Traj_xR Abs grid_incR 1 number of path coordinates nopc num_preR 3 number of data columns preceding path coordinates Compute the sign of the slope for the redirection paths where negative slopes change the sign of lateral coordinates For example e negative slope o traffic side impact on right side of road CSRL left side of hazard o non traffic side impact on left side of road CSRL left side of hazard e positive slope o non traffic side impact on right side of road CSRL right side of ha
95. es the data in arrays for ready access during the analysis The flow chart for this program module is shown in Figure 30 Determine Number of Alternatives and Maximum Array Size of Hazard Variables read from worksheet Alternatives Redimension Hazard Array Variables For iALT 1to num_ALTS For each alternative Next iALT Yes a i ni aoe d a Figure 30 Flow chart for ModulePOChaz C 88 Program Variables max_num_haz maximum number of hazards for any alternative num_ALTS number of alternatives in the analysis HM slope of line segment connecting hazard ends HazRow Current row number with hazard information on worksheet Alternatives AltOffset Current column number with hazard information on worksheet Alternatives R Radius of Point hazards inches oHx oHy oHzrd_Capacity oHzrd_Connection Identifies LON hazard attached to END TERMINAL oHzrd_EFCCR45 oHzrd_Height oHzrd_GenType oHzrd_Prcent_PRV oHzrd_Prent_RR oHzrd_Type oNum_Hazards Procedure The number of alternatives is read directly from the RSAPv3 worksheet Alternatives and the maximum array size for the hazard variables is based on the maximum number of hazards for any alternative case The total number of hazards also includes the area hazard rollover which is automatically added to the hazard list for each alternative case This increases the number of columns i
96. ext box indicating the alternative they would like to copy This text box works in conjunction with the Copy Alt button next to it First the user enters the integer value of the alternative they want to copy and then they press the Copy Alt button to affect that action The new alternative is automatically added and the IblIAltNum value is incremented by one i e if there are three alternatives and the user copies the 2 alternative the new copied alternative will be alternative 4 btnCopyAlt_ClickQ IbIAIt2Delete The user can enter a number in this text box indicating the alternative they would like to delete This text box works in conjunction with the Delete Alt button next to it First the user enters the integer value of the alternative they want to delete and then they press the Delete Alt button to affect that action The selected alternative is automatically removed and the IblIAltNum value is decreased by one i e if there are three alternatives and the user deletes the 2nd alternative the 3 alternative will be become alternative 2 btnSortAlts_ClickQ This macro simply sorts the user entered information into station order It is not necessary to press this button it is only provided for the convenience of the user to organize the information rbtnAlt1_ClickQ Five radio buttons are displayed in the a frame i e Frame2 with the label View Edit All five buttons work exactly the same so only
97. ext button is hidden unless all the yellow INPUT cells have values ptnPrevPrjInfo ptnNextSegments Figure 6 RSAP Controls Dialog Traffic Information C 20 btnDefaultTraffInfo_Click Selecting the Restore RSAP Defaults on this form executes this method which is active only on the Traffic Information worksheet i e only information on the Traffic Information worksheet is deleted or overwritten The user is asked if the really want to delete all the traffic information if they respond YES then all the rose INPUT 2cells are cleared of their content and the appropriate default values are copied from shDefaults The Highway Info gt next button remains hidden unless all the yellow INPUT cells have values btnPrevProjInfo_Click The lt Project Info button returns the control to the previous Project Information worksheet Selecting the button executes this method which simply selects the project Information worksheet i e shprojInfo and sets the value of frmRSAPcontrols mpControls value 0 btnNextSegments_Click The Highway Info gt button advances the control to the Road Segments worksheet The button will not appear until there is user input in all the yellow cells in the Traffic Information worksheet i e style Input Selecting the button executes this method which simply selects the Road Segments worksheet i e shRdSegs and set the value of f
98. f rollover as a function of roadside slope 66 Table 2 Adjustment Factor Lookup Table for probability of rollover as a function of roadside Slope and vertical grade a ac25 250 ce ss2c dacs on es euses saedeaeas beat casstenaweeseaea 67 Table 3 Adjustment Factor Lookup Table for probability of rollover as a function of roadside slope and horizontal curve radius eccceeeseceeeseeeseseeeesteeeenaees 68 Table 4 Example Output to POC Scratch worksheet ceeceeeseeeeeeeeceeececeeeeeeneeeeesaeees 86 C 4 INTRODUCTION This Manual is one of three reports which accompany this software including a USER S MANUAL and an ENGINEER S MANUAL This manual the PROGRAMMER S MANUAL is intended for those that are maintaining or modifying the actual computer code for RSAPv3 Most typical changes and updates to RSAP can be accomplished using the many lookup tables and do not require any changes to the actual code Instructions for making changes to the lookup tables are described in the ENGINEER S MANUAL When updating the program the first and preferable choice is to try and make the change using the lookup tables and to change the underlying code only when absolutely necessary This manual documents the program architecture the data table specifications and the pseudo code and provides the necessary background needed to understand the program structure The USER S MANUAL is a reference for program users of all experience levels
99. fective average velocity used in crash cost calculations Procedure The first step is to compute the probability of a rollover since the last collision event based on roadway roadside conditions i e Proll2 The following line of the code calculates Proll2 as the total probability for rollover from the point of encroachment to the current trajectory position minus the probability of rollover from the point of encroachment to the previous collision event Proll2 SumPRslopexL LT ProllO For example Figure 44 illustrates a trajectory path intersecting two hazards In Figure 44a the vehicle is about to impact the first hazard at Point B In this case N SumPRslopexL 2 P R slope Psia Ps nc Li i Where SumPRslopexL is the sum of the probabilities for rollover at each increment of the path from Point A to Point B LT is the maximum length of the path i e length from Point A to Point E and Proll0 is zero i e there were no events prior to the encroachment at Point A In Figure 44b SumPRslopexL is the sum of the probability for rollover at each increment of the path from Point A to Point D LT is the maximum length of the path 1 e length from Point A to Point E and Proll0 is the sum of the probability for rollover at each increment of the path from Point A to Point B C 143 Line Hazard End of trajectory Point Hazard a Impact with first hazard Line Hazard End of trajectory Point Hazard b I
100. for that alternative to every row in the column between 5 and segs 4 Next iAlt Next iSegs Delete the validation rules in D5 H24 Set the style in D5 H24 to Normal 2 to prevent user input Protect shXsection Enable event processing Position the cursor at DS btnSaveXsection_Click This button is initially hidden and is only revealed if the Assign X Sections to Segs and Alts button is pressed The purpose of the macro is to save a new or edited cross section definition that the user has established in the detailed cross section input area When the user has entered all the information and is satisfied with the cross section this button is selected if the user wants to save the cross section to use in RSAP The macro proceeds as follows Ask the user for a name for the x section Select Case xSectionName Exit Sub Case frmRSAPcontrols lbxsectionNames value Case Loop through the name database and find the row associated with that name Case Else Write the new name at the end of the database list in a new row End Select Unprotect shXsection Disable event processing Write all the information in the user input area into the database row for the named slope Call moduleXsection buildXsectionListBox to re build the list box view Call moduleXsection xsectionInList Enable event processing Position the cursor to DS Protect shXsection Hide btnSaveXsection Hide btnDeleteXsection btnDeleteXsection_Click This button is init
101. form module designates a VBA code module txt designates a text box form rbtn designates a radio button form and C 9 e txt designates a text box Subroutine and method names generally start with one of the fore going designations to help clarify the type of object that is being instantiated RSAP uses several worksheet cell styles to inform the user about where input can and cannot be placed RSAP uses the following styles which can be found in Excel under the Home gt Cell Styles group e Input this style indicates cells where the user must enter information This is the project specific information so there are no default values This cell style has a yellow highlighted background to indicate user input is expected This style is also by default unprotected e Input2 this style indicates cells where the user may provide input but where RSAP will provide a default value The cells are high lighted rose and are unprotected e Heading1 Heading2 Heading3 Heading4 Normal 2 these four styles are used to format the RSAP worksheets with a variety of font sizes and font types They user cannot change these cells as they are protected RSAP generally uses standard Excel format for number with one important exception A custom style O 00 0 00 has been added to display Station number in the traditional highway engineering format i e the location 345 67 feet from the start of the proj
102. gment the project btnEncr_Click estimate the number of encroachments shPrjInfo Select go back to the Project Information worksheet Re protect all user sheets Re enable events Re enable screen updating Re enable alerts End if btnProjInfoClear This method is executed by pressing the Clear User Information button shown in Figure 4 Unlike btnNewPrj_Click which clears all user input in the workbook this method only clears information on the Project Information worksheet Show Msgbox asking if the user really wants to clear the information If user_choice no then Exit Else Unprotect shPrjInfo shProjlInfo Range B5 ClearContents jfrmRSAPcontrols btnNextTraffInfo Visible false Protect shPrjInfo End if btnPrjInfoDefaults The purpose of this method is to allow a user to restore the RSAP default information to the rose colored cells i e style Input2 on the Project Information worksheet Any information that has been changed in these cells will be overwritten Show Msgbox vbYesNo asking if the user really wants to clear the information and restore the RSAP defaults If user_choice YES then Unprotect shPrjInfo shProjInfo Range B5 I5 ClearContents frmRSAPcontrols btnNextTraffInfo Visible false Protect shPrjInfo End if btnNextTraffInfo_Click The Traffic Info gt button advances the control to the Traffic Information worksheet The button will not appear until t
103. greater than lateral position of hazard and the lateral trajectory at the current point is less than the lateral position of hazard and if there is no rollover or end of trajectory path then path crossed barrier from right side Elself y gt Hy0 BHW _ And y gt Application Min oHy oHy2 BHW _ And yj lt Hyl BHW _ And y lt Application Max oHy oHy2 BHW Then CSRL right collision side right used for determining sign of angle for redirection trajectories Collision true End If If a collision has occurred on either side of the hazard then 1 compute probability and associated costs of a rollover occurring prior to the collision with the hazard 2 compute crash statistics and associated costs for collision with the hazard 3 determine probability of PRV 4 evaluate redirection trajectories for secondary collisions and 5 continue evaluating current path post penetration for secondary collisions 1 Compute Rollover Statistics and Cost If the trajectory is not a redirection trajectory then the program calls subroutine subRolloverM2b to calculate rollover statistics The subroutines are presented in a later section of this Manual and the details of the rollover model are provided in the ENGINEER S MANUAL If Collision true Then If redir_flag lt gt 1 Then Call subRolloverM2b Initialize Rollover Variables SumV2 0 V2avg 0 C 117 N 0 End If 2 Compute Crash Statisti
104. h e VehCharac 7 vehicle width e WVehCharac 8 distance from cg to front of vehicle e WVehCharac 9 cg height e WVehCharac 10 crash cost adjustment factor e x x coordinate of initial redirection point e y y coordinate of initial redirection point e grid_inc longitudinal increment of original trajectory path e Max_L maximum length of original trajectory path C 132 Program Variables The following are a list of variables defined in the Module Grid_incR Max_Traj_xR nopcR num_preR POC probability of occurrence for this trajectory path Pass Through Variables The following are a list of variables that are not directly used in this subroutine but are required in the probability of collision analysis of the redirection paths i e call of ModulePOCanalysis CountCSg number of cross section coordinates in CSglob count_pene_RSAP count_RR CS collision side e g traffic side non traffic side CSglob coordinates of global terrain cross section d0 distance to hazard coordinate EFCCRi total cumulative EFCCR the current trajectory EFCCR_RR cumulative EFCCR for rollover after redirection for current hazard EFCCR_tot cumulative EFCCR for the current hazard iDP departure point iLDS lane departure side impact_Count_NTS impact_Count_tot impact_Count_TS oNum_Hazards number of hazards in current alternative oHzrd_Capacity hazard capacity oHzrd_Connection Identifies LON hazard attache
105. h statistics for the rollover event 4 determine probability of redirection and 5 pass this information back to parent module The details of the development of this procedure are provided in the ENGINEER S MANUAL Input Variables The following are a list of variables passed from the parent module e iALT current alternative e EFCCRi total cumulative EFCCR the current trajectory e EFCCR RR cumulative EFCCR for rollover after redirection for current hazard e K hazard number e num_traj_seg cumulative number of trajectories for this segment e oHzrd_Capacity hazard capacity e oHzrd_EFCCR65 hazard severity Effective Fatal Crash Cost Ratio for impact speed of 65 mph e oNum_Hazards number of hazards in current alternative e oHzrd_Height height of hazard e oHzrd_Prent_RR percent of rollover after redirection from crash statistics e oHzrd_Type hazard type C 125 POC probability of occurrence for this trajectory increment e g probability of collision Theta0 impact angle v impact velocity VehCharac 1 RSAPv3 vehicle name VehCharac 2 FHWA vehicle class VehCharac 3 percent of traffic mix VehCharac 4 RSAPv3 vehicle type M C T VehCharac 5 vehicle weight VehCharac 6 vehicle length VehCharac 7 vehicle width VehCharac 8 distance from cg to front of vehicle VehCharac 9 cg height VehCharac 10 crash cost adjustment factor Program Variables The following are a list of var
106. he RSAP controls dialog box is shown in Figure 2 and is initiated using the Show method executed from modulesTools StartRSAP The RSAP controls dialog C 11 box is defined in the object frmRSAPcontrols which is a standard VBA User Form The main portion of the form a multipage form i e mpControls with a label in the lower left i e In NextStepHint and six command button forms i e btn UserMan btnEngMan btnRSAPhep btnSave btnSaveAs and btnExit Figure 2 also shows the tab and button bindings indicating which subroutine or method is executed when the button or tab is pushed frmRSAPcontrols has no input variables constants or public variables other than the standard VBA User Form properties Pressing the tabs executes the frmRSAPcontrols mpControls_Change method which activates the appropriate worksheet indicated on the left side of Figure 2 and sets the value of frmRSAPcontrols mpControls value Each of the tabs will be discussed in detail below The buttons that appear in the context sensitive area of Figure 2 are determined by the value of frmRSAPcontrols mpControls value The six command buttons at the bottom of the RSAP Controls Dialog shown in Figure 2 are always visible and available to the user Pressing the buttons activates the method indicated in Figure 2 For example pressing the User s Manual button executes the frmRSAPcontrols btnUserMan_Click method which opens a window with the User s Manual in it
107. he list in alphabetical order to save on the severity worksheet With shSeverity Sort SortFields Clear SortFields Add Key Range Cells 4 1 Cells botRow 1 SortOn xlSortOnValues Order xlAscending DataOption xlSortNormal SortFields Add Key Range Cells 4 9 Cells botRow 9 SortOn xlSortOnValues Order xlAscending DataOption xlSortNormal SetRange Range Cells 4 1 Cells botRow 24 Header xlNo MatchCase False Orientation xITopToBottom SortMethod xlPinYin Apply End With btnCategory_ClickQ This method works exactly like btnAlpha_Click except the data is sorted by the hazard category in column 11 i e column K rather than 1 btnSeverity_ClickQ This method works exactly like btnAlpha_Click except the data is sorted by the severity in terms of the EFCCRe s in column 5 i e column E rather than 1 btnCapacity_Click This method works exactly like btnAlpha_Click except the data is sorted by the hazard capacity listed in in column 8 i e column H rather than 1 btnBk2Alts_ClickQ This button selects the Alternatives worksheet and sets the frmRSAPcontrols mpControls value 3 This returns the view and control to the Alternatives worksheet modulesTools editSeverities This is a hidden key stroke macro meaning that it is not initiated from the RSAP Controls Dialog user interface and is not mentioned in the User s Manual Typical users will not need to edit the information o
108. here is user input in cell B5 of the Project Information worksheet Selecting the button execute this method which simply selects the Traffic Information worksheet i e shTraffInfo selects cell C3 in that worksheet and set the value of frmRSAPcontrols mpControls value 1 TRAFFIC INFORMATION WORKSHEET The Traffic Information worksheet is used to collect information from the user about the traffic volume traffic mix and vehicle properties as shown in Figure 5 The rose colored cells may be changed by the user but contain RSAP default values Selecting the Traffic tab in the RSAP Controls Dialog or selecting the Traffic Information worksheet tab will set the frmRSAPcontrols mpControls Value property to 1 display the context sensitive buttons as shown in Figure Sand activate the Traffic Information worksheet i e shTraffInfo The Traffic Information view of RSAP Controls shown in Figure 6 Figure 4 includes four command buttons which will be described below The user can either select buttons on the RSAP control form or select a yellow or rose user input cell on the worksheet in order to enter information The worksheet itself contains the following formulae in the protected cells indicated Cell Formula C6 C 3 14 C 4 100 Project Information B 7 2 C7 C 3 1 C 4 100 Project Information B 7 C8 IF C 5 Construction C3 IF C 5 End of Life C 7 C
109. hment Side Opposing Right Then CSy0 oMedianHW oRoadWOP iDir If Encroachment Side Primary or Opposing Left Then CSy0 oMedianHW iDir Elself hwyType Undivided Then If Encroachment Isde Primary or Opposing Right Then CSy0 oRoadWPR iDir If Encroachment Side Primary Left Then CSy0 oRoadWOP iDir If Encroachment Side Opposing Left Then CSy0 oRoadWPR iDir Elself hwyType One Way Then If Encroachment Side Primary Right Then CSy0 oRoadWPR iDir If Encroachment Side Primary Left Then CSy0 0 End If The final steps are to translate the cross section coordinates so that it starts at the local origin and to calculate the vertical slope between each cross section break point Note that the vertical slope CSloc i 3 is only used for resampling the cross section data in ModulePOCtraj so that a point to point comparison can be made with crash cases in the crash reconstruction database when selecting trajectories for the analysis For i 1 To iXsect If CSloc i 1 lt gt Then CSloc i 1 CSloc i 1 iLDS iDir CSy0 iDir compute slope values C 76 Ifi 1 Then CSloc 1 3 0 Else CSloc i 3 vertical slope End If End If Next i ymax maximum lateral extent of the cross section data Global Cross Section Geometry and Corresponding Baseline Probability of Rollover The following lines of code read in and process the complete cross section profile of the curren
110. hted average of the four individual scores In some cases the similarity scores might be very high for certain characteristics and low for others In these cases the weighted average score may result in a relatively high value To reduce the likelihood of such a trajectory case being selected for the analysis a cutoff value is set for each characteristic score When an individual score falls below the cutoff value then its value is reduced by half in order to sufficiently lower the composite score and minimize its chance for selection The cutoff values for each characteristic are defined on the RSAPv3 Control Form as shown in Figure 33 The default value is 0 7 C 100 RSAPv3 Controls xT Figure 33 RSAPv3 Controls Dialog Default Analysis Settings The following lines of code read the cutoff values from the RSAPv3 Control Form For i 1 To Count SIcutoff CDbl frmRSAPcontrols Read cutoff value for x section score S2cutoff Read cutoff value for posted speed limit score S3cutoff Read cutoff value for vertical grade score S4cutoff Read cutoff value for Horizontal Curve score If Slscore lt Slcutoff Then SIscore SIscore 2 End If If S2score lt S2cutoff Then S2score S2score 2 End If If S3score lt S3cutoff Then S3score S3score 2 End If If S4score lt S4cutoff Then S4score S4score 2 End If C 101 The weight assigned to each of the characteristic scores is al
111. i Select Trajectories for the Analysis Once the individual scores for each of the four criteria have been computed and combined into a single representative composite score for the trajectory case RSAPv3 then sorts the trajectory cases in descending order based on their composite score and selects the trajectory cases with the highest scores for use in the analysis RSAPv3 selects only those trajectories that have a composite score of 0 93 or higher or until the minimum number of desired trajectory cases are obtained The minimum number of trajectories is defined on the RSAPv3 Control Form shown in Figure 33 and the default value is 10 For some road segments with very common roadside characteristics there may be a relatively large number of trajectory cases with a score higher than 0 93 particularly as C 102 more and more cases are added to the database Although the accuracy of the analysis is expected to increase as the number of applicable trajectories increases the time for completing the analysis will also increase It is assumed that a maximum of forty trajectories will provide sufficient accuracy with acceptable analysis time however the maximum number of trajectory cases is defined on the RSAPv3 Control Form where it can be readily changed The following lines of code 1 sort the composite scores in descending order 2 selects the trajectories cases with the highest scores for use in the analysis 3 determines the lowest
112. iables defined in the Module POR effective probability of redirection given collision conditions and probability of collision event PORV effective probability of truck rolling over hazard given collision conditions and probability of collision event POC probability of collision and or occurrence of current trajectory path PRB probability of rolling over hazard given current impact conditions ignoring probability of penetration PRR probability of rollover after redirection given current impact conditions ignoring probability of penetration and rolling over the barrier KE kinetic energy of vehicle KK hazard number set for rollovers Capacity barrier capacity in units of energy ISeverity impact severity m vehicle mass Count_pene_RSAP number of penetrations on current hazard VOrv modified post impact velocity die to loss of energy during redirection and rollover WRR probability of rollover after redirection considering probability of penetration and rolling over the hazard WRV probability of rolling over barrier given current impact conditions considering probability of penetration C 126 e WR probability of redirection considering probability of penetration rollover barrier and rolling over after redirection e WP probability of penetration given current impact conditions Procedure Probability of Penetration due to Structural Failure or Vaulting The program uses two different approaches for determining penetration
113. ially hidden and is only revealed if the Assign X Sections to Segs and Alts button is pressed The button removes a named cross section from the RSAP database of cross sections and re builds the list box and validation menus The procedure is as follows Ask user if they really want to delete the cross section If YES then Find the row in column 32 with a name that matches the selection Unprotect shXsection Disable event processing Clear the row in column 32 where matching the cross section name Copy the next row to the last row Paste the selection into the row just cleared Call moduleXsection buildXsectionListBox to re build the list box Call moduleXsection xsectionInList to check that the name is valid Enable event processing Protect shXsection Position the cursor in cell D5 Hide the Save and Delete buttons End if btnAssign_Click This macro allows the user to select different cross sections for each segment and each alternative Each cell in the input area 1 e D5 H24 represents a different segment and alternative The user can choose a cross section for each cell The macro proceeds as follows Unprotect shXsection Disable Event Processing alts Read the number of alternatives from shAlternatives Range C3 hwyType Read the highway type from shRdSegs Range E5 segs Read the number of segments from sRdSegs Range D64 Set the style of the detail cross section input area to normal 2 to prevent input For iSeg 1 to segs For
114. identified by the user for each alternative Lastly the expected crash cost of a severity s crash E CC lSevs is multiplied by the result to convert the result to units of dollars Combining all the terms yields C 6 n 1 E CC y um Ly f base EAF y encr m A l i 1 k 1 j Me P Trj N Haz Encr P Sev Trj N Haz E CCs Sevs 1 While the encroachment method is conceptually straight forward estimating the three conditional probabilities at the heart of the method can be difficult and computationally demanding since tens of thousands of possible encroachments must be evaluated Each of these conditional probabilities are based either on observed encroachment and crash data Since the computations can be complicated a computer program like RSAPv3 is the most convenient way to implement the encroachment based approach in roadside safety analysis Each of these condition probabilities is implemented within RSAPv3 as a module The results of the analysis i e E CC n m are used in the benefit cost module to compare roadside design alternatives Project specific data is collected from the user through a series of worksheets within the RSAPv3 user interface This project specific data is used in conjunction with models based on research stored in other worksheets to preform calculations which are coded in RSAPv3 Unlike earlier versions of RSAP RSAPv3 does not use a Monte Carlo simulation method to calculate the probabilit
115. in Database Point to Point comparison of Compute cross section each trajectory cross section similarity score for each coordinate with project cross trajectory case section 1 Compute posted speed limit similarity score for each trajectory case 2 Compare posted speed limit of each trajectory case with posted speed limit for project Compute vertical grade Compare vertical grade of aa roadway in each trajectory case sirollestty score for gach with vertical grade in project tacon case Compute horizontal curve similarity score for each trajectory case S4 Compare horizontal curve radius in each trajectory case with horizontal curve radius in project Assign weight for each score Read from RSAP Control Form 4 Compute weighted composite score for each trajectory case Sort trajectories in descending order based on composite score Minimum and maximum number of trajectories Defined on RSAP Control Form Select trajectories with highest scores for use in analysis Transform trajectory path data to local coordinates based on traffic direction and departure side Return to POCmain Figure 32 Flow chart for Module POCtraj C 94 Input Variables The following are a list of variables passed from Module POCMain CSloc roadside cross section profile in local coordinates iALT alternative number iDirection traffic d
116. in column 32 SlopeNames Set the Rowsource of lbxsectionNames SlopeNames Sort the names in alphabetical order The result of this macro is that the list of names in column 32 appear in the IbxsectionNames writeXsectionInfo This macro transfers the cross section information from the user input area where new cross sections can be defined and existing cross section can be edited to the hidden database area of shXsection The macro first looks to see if the name is already in use If it is the new information is used to over write the old data If the name is not already in the list it is added and the new cross section information is associated with the new name xsectionInList This macro checks to ensure that the default cross sections selected in the segment and alternative cells of shXsection are valid cross section that are in the list in column 32 If a name is not found the user is notified and asked to pick a valid cross section name from IbxXsectionNames The macro will not allow the user to proceed until a valid name is selected ANALYZE Unlike most of the tabs on the RSAP Controls Dialog the Analyze tab is not associated with a particular worksheet Instead the buttons available on this form control C 36 the execution of the analysis The form has both a simple view and a more complicated view where analysis settings can be made as will be described shortly Selecting the Analyze tab in the RSAP Control
117. ints and reads in the width of the hazard from worksheet Alternatives A sketch of a line hazard with dimensions is illustrated in Figure 31 Width Line Hazard OHX oHy3 HM slope OHx OHy Figure 31 Sketch of line hazard dimensions If oHzrd_Type iAlt K L Then oHx iAlt K 1 read longitudinal coordinate oHx oHy iAlt K 1 read lateral coordinate oHy sideStart o Hx iAlt K 2 read longitudinal coordinate oHx gt oHy iAlt K 2 read lateral coordinate oHy2 sideEnd oHy iAlt K 3 read hazard width 12 convert to feet from inches Compute slopes of piecewise linear segment defining hazard C 91 If oHx iAlt K 2 oHx iAlt K 1 Then oHx iAlt K 2 oHx iAlt K 2 0 1 guard against undefined slopes End If HM iAlt K oHy2 oHy oHx2 oHx Point hazards are defined by a point and radius The coordinates of the center of the hazard and the hazard diameter are read from the worksheet Alternatives Elself oHzrd_Type iAlt K P Then o Hx iAlt K 1 longitudinal coordinate of hazard center point oHy iAlt K 1 lateral coordinate of hazard center point sideStart R iAlt K Diameter 2 12 converted from inches to feet End If oHzrd_Connection iAlt K 0 Next K After all the hazards have been defined the final task is then to associate terminal ends to their mating longitudinal barriers e g guard
118. irection i e l primary 1 opposing iLDS encroachment side 1 right 1 left iSeg segment number iVeh vehicle type number grid_inc longitudinal increments of trajectory path oPDCR horizontal curve radius oPDG roadway vertical grade oPSL posted speed limit SheetName name of the worksheet containing the database of reconstructed trajectories num_veh total number of vehicle types ymaxp maximum extent of cross section profile in local coordinates Program Variables The following are a list of variables defined in the Module TrajectoryData variable array that stores the entire trajectory database to facilitate quick access to the data delta_y ateral increment for resampling cross section profiles myrow first row with data on the trajectory grid worksheets num_pre Number of data columns preceding the trajectory path information in the trajectory databases num_traj total number of trajectories selected for the analysis SumErrSq sum of the errors squared for comparing roadside cross section profiles TrajScore trajx trajy traj_select y lateral coordinate of resampled cross section profile of project road segment z vertical coordinate of resampled cross section profile of project road segment yt lateral coordinates of cross section profile from trajectory database zt vertical coordinates of cross section profile from trajectory database st slopes of cross section profile from trajectory datab
119. lculated The macros that execute the benefit cost module are contained in moduleResults The actual benefit cost calculations are done as worksheet functions on the Results worksheet PROCEDURE featureResults This macro is executed automatically when the Results worksheet is activated and also when the Feature Report button is selected as shown in Figure 18 The purpose of the macro is to process the crash prediction and severity information stored on the hidden shPOCscrach worksheet and display it as a summarized report of the collisions with each roadside feature i e hazard defined in the alternatives The procedure is as follows Start At row 10 Search Column A until the value is blank myRow The row before the blank column is the last row Sort range Al0 myRow21 by Column 2 Alternative number Column 1 Segment number Column 8 Hazard number Column 4 Traffic side C 146 Column 5 Vehicle type Print the run date time Excel version and RSAP version in the Feature Report Select shPOCscratch Range B11 gt the alternative column Set up initial values Row 9 Totalcrash 0 Prvcrash 0 Redirectrollcrash 0 Vsl shPrjInfo Range F18 value gt value of statistical life Clear shResults Range A9 I5000 Do Until alternative is blank Read the row of data from shPOCscratch Alt selection offset 0 0 the alternative number Seg selection offset 0 1 the segment number Haz selection offset 0 6 the hazard numb
120. lection of trajectories for the analysis is based on a point to point comparison of the roadside cross section profile to those in the crash reconstruction database Therefore the roadside cross section coordinates for the current encroachment location must be converted to the local reference frame of the crash cases in the database to enable a direct comparison of the cross section profiles For example consider a primary left encroachment onto a median with cross section defined by the coordinates listed in Figure 27 In order to compare the median cross section to those in the database the median cross section profile must be transformed from global coordinates e g as shown in the upper table in Figure 27 to the local coordinate reference frame e g as shown in the lower table in Figure 27 48 lt Opposing Direction Global Coordinates of Median Profile 35 Global Coordinates ere Lateral Offset from iad Center Line ft 24 0 30 20 o 0 10 20 30 24 16 0 3 0 4 5 20 0 25 z 12 24 0 Primary Left Encroachment Transformed to Local Coordinates Lateral Offset from Median Center Line ft ey Local Coordinates i _ Lateral Offset from Encroachment Point ft i so ae et kig mep e i 4 0 25 20 A 5 36 3 o3 7 gt Primary Direction a o Figure 27 Illustration of transforming the median cross section coordinates from the global referenc
121. lection offset 30 2 value p_hcurvAdj Selection offset 30 3 value p_numLaneAdj Selection offset 30 4 value o_gradeAdj Selection offset 30 5 value o_hcurvAdj Selection offset 30 6 value o_numLaneAdj Selection offset 30 7 value spdLimAdj Selection offset 30 8 value InWidthAdj Selection Offset O 30 Value shldrWidthAdj Selection offset 30 9 value accessAdj Selection offset 30 10 value rumbleAdj Selection offset 30 11 value terrainAdj Selection offset 30 12 value shRdSegs Range E8 value increment for the next row Selection offset 1 0 Select The road characteristics will have been previously written into shRdSegs Range A71 P90 by the segChars subroutine so this subroutine starts by selecting cell A71 the top left cell of the road characteristics table Procedure The procedure is to read in the start and end station for each segment its ADT and the highway type and call the adjust function to find the appropriate base encroachment frequency in the Base Encroachment Frequency lookup table on shEncrAdj shRdSegs Range A71 select do until selection value segment selection value 33 6 the segment number is in colA C 56 startSta selection offset 0 1 value endStat selecton ofset 0 2 value segmentLength endSta startSta if segmentLength is blank or negative then Display error message and exit Else ADT selection offset 0 3 value hwyType range E5 value
122. mate the Redirection Rollover crashes If Num_reroll is not 0 or blank then redirectionrollcrash Num_reroll encr NumEncr vehicleMix redirectionrollcrash Crashcost vsl selecton offset 0 19 encr vehicleMix Crashcost Else redirectionrollcrash 0 End if End if segResults This macro calculates the segment cost information by summing portions of the feature report by segment and alternative This macro is activated when the Segment Report button is selected and results in a view similar to that shown earlier in Figure 16 C 148 printReports This macro prints the three reports shown on the Results worksheet using the worksheet PrintOut and PageSetUp methods The resulting printouts are identical to what is displayed in the three reports on the Results worksheet The procedure is as follows Enable the Excel Ribbon Toolbar Top Row is 9 Do Until the cell ROW column C is blank Bottom Row Row Set featurerange shResults range cells 1 B cells BottomRow J With shResults Make all columns visible Clear PrintArea Print Feature Report PageSetUp PrintArea featurerange PrintOut to print with copy and Preview TRUE Print Segment Report PageSetUp PrintArea N1 AA43 PrintOut to print with copy and Preview TRUE Print Benefit Cost Report PageSetUp PrintArea AB1 AH15 PrintOut to print with copy and Preview TRUE End With Turn off Excel Ribbon Toolbar DEVELOPMENT AND MAINTENANCE TOOLS RSAPv3 contains a variety of macro
123. ment Else if Begin Stations are the same but the Ends are different then Copy the longer segment and add a row Set the End Station of the first row to the smaller value Set the Begin station of the 2 row to the end station of 1 Else if 1 Begin Sta lt the next and next End Sta gt 1 Begin Sta Split segment into two rows and adjust the begin and end End if Increment the row Loop Check to be sure all segments are contiguous allOK TRUE Do Until Begin Sta is blank C 58 If current Begin Sta gt current End Sta then allOK FALSE End if if current Begin Sta gt next Begin Sta then allOk FALSE end if if current and next Begin Sta are same but Ends are not then allOK FALSE End if Increment row Loop Seg stating segment is 1 Do Until Begin Sta is blank or number of segments gt 20 If begin and end stations of current and next row are same then Write seg into row E Else Seg seg 1 End if CRASH PREDICTION MODULE INTRODUCTION This macro computes the probability of a collision given that a vehicle has encroached onto the roadside or median in order to accomplish the following portion of the main RSAP governing equation l m 1 P Cr Encr y gt P Trjx N Haz Encr k 1 j 1 This is accomplished by directly projecting encroachments from the reconstructed trajectory paths in the NCHRP 17 22 crash database onto the roadside or median and looking for intersections between the trajectories and hazard locations This approach
124. mpact with second hazard Figure 44 Illustration of trajectory path intersecting two hazards The next step is to compute the effective probability for rollover along the current path segment The effective probability for rollover is defined as the probability of rollover given the various roadway and roadside conditions i e Proll2 times the probability that the vehicle penetrated the previous hazard POCroll Proll2 POC 1 POCroll0 The term POC 1 POCroll0 in the equation above represents the probability that the vehicle penetrated the previous hazard where POC can be defined as POC POC PenHaZg Where POC is the probability of collision with the previous hazard PenHazp is the probability of penetrating the hazard and POC is the resulting probability of the vehicle getting to the current increment The term POCroll0 1 POCo thus POC POC PenHazo l o a 1 POCroll0 1 1 P0G me C 144 The next step is to compute the average crash cost for a rollover along the current segment of the trajectory path The crash cost is based on the velocity cubed v at the time of rollover Recall that in subRolloverM2a the velocity cubed was computed at each increment along the path and stored in variable V3avg This value could be used directly in the calculation of EFCCR however the subroutine SubCollision_Statistics which is used to compute crash cost statistics requires velocity as input The re
125. mpute the probability of rollover and associated rollover crash costs When a collision is detected in ModulePOCanalysis the probability of occurrence must be determined in order to compute the statistical cost of the collision event The probability of occurrence POC is dependent on the complete history of trajectory path up to the current path coordinate including impact with previous hazards and the probability of rollover occurring prior to impact with the current hazard For example if a trajectory path first intersects one hazard and then another then the probability of the second impact occurring is dependent on the vehicle getting to the first hazard without rolling over penetrating the first hazard not rolling over after the penetration and not reaching zero velocity prior to collision with the second hazard This section of the program computes the probability of the trajectory resulting in a rollover before reaching the hazard The basic procedure is to 1 compute the probability of a rollover based on trajectory path length since the last collision event roadway roadside conditions and probability of getting to the current path location 2 compute the expected crash cost for the rollover event based on the average velocity cubed and probability of occurrence and 3 return relevant statistical information to ModulePOCanalysis The flow chart for this program module is shown in Figure 43 C 141 subRolloverM2b Compute pro
126. n The traffic mix for the roadway segment and the vehicle characteristics e g mass dimensions etc are read from the RSAPv3 worksheet Traffic Information Twelve columns of information are read from this sheet and are stored in the array variable called WehCharac where VehCharac 1 RSAP Vehicles Types by name Motorcycles Passenger Vehicles Trucks VehCharac 2 FHWA Vehicle Class Designation VehCharac 3 Percent of Traffic Mix VehCharac 4 RSAP Vehicle Type Designator M C or T VehCharac 5 Vehicle weight Ibs VehCharac 6 Vehicle length ft VehCharac 7 Vehicle width ft VehCharac 8 Longitudinal distance from front of vehicle to center of gravity ft VehCharac 9 Vertical distance from ground to center of gravity ft VehCharac 10 Crash cost adjustment factor VehCharac 11 RSAP worksheet name containing trajectory information VehCharac 12 RSAP worksheet name containing redirection trajectory information Do Until all traffic data has been read If vehicle mix is not 0 Then num_Veh num_Veh 1 For j 1 To 12 VehCharac num_Veh j data in column j Next j End If Loop Define Hazard Information Information about each of the hazards including hazard name hazard type and geometric coordinates are read from the RSAPv3 worksheet called Alternatives The program calls ModulePOChaz to perform this task which returns the following inform
127. n the Severity worksheet while it is visible it is C 48 protected against user input If the information in the hazard data base does need to be edited or updated however this macro can be used to do so To execute the macro go to the Severity worksheet and use the key stroke CTRL SHIFT H The macro is a toggle so the first time the key stroke is pressed the Severity worksheet is unprotected and the Excel ribbon interface is turned on All the Excel interface features are turned on and the worksheet can be edited like any typical worksheet The second time the CTRL SHIFT H key stroke is issued the ribbon interface is turned off the sheet is re protected and the internal hazard menus are sorted and rebuilt using the following code and RSAPV3 is re started shSeverity Select select the severity worksheet if the headings are on turn them off and re build the hazard menus otherwise turn them off and allow editing If Active Window DisplayHeadings TRUE Then Else Start at row 4 Count the rows until a blank cell is found The last non blank cell is the bottomRow Sort the data fields in the worksheet by hazard category i e column 11 Unprotect and make visible shPrgData Clear the old hazard menu definitions in Range J3 T48 Copy the category names from shSeverity to shPrgData Rebuild the context sensitive menus by resizing the range names for each hazard category Turn off display headings
128. n the array size by one num_ALTS read number of alternatives from Alternatives worksheet max_num_haz number of hazards in the alternative with the most hazards ReDim oNum_Hazards num_ALTS ReDim oHzrd_Type num_ALTS max_num_haz 1 ReDim oHzrd_Name num_ALTS max_num_haz 1 ReDim oHzrd_GenType num_ALTS max_num_haz 1 ReDim oHzrd_EFCCR45 num_ALTS max_num_haz 1 ReDim oHzrd_Prent_PRV num_ALTS max_num_haz 1 ReDim oHzrd_Prcnt_RR num_ALTS max_num_haz 1 ReDim oHzrd_Capacity num_ALTS max_num_haz 1 ReDim oHzrd_Height num_ALTS max_num_haz 1 C 89 ReDim oHzrd_Connection num_ALTS max_num_haz 1 ReDim oHx num_ALTS max_num_haz 1 2 ReDim oHy num_ALTS max_num_haz 1 3 ReDim HM num_ALTS max_num_haz 1 ReDim R num_ALTS max_num_haz 1 The hazard information on worksheet Alternatives is then read for each alternative case The first step is to determine which side i e left or right of the baseline the hazard is located i e Start Side and End Side on worksheet Alternatives HazRow 10 starting row for hazard data on worksheet Alternatives For iAlt 1 To number of alternatives AltOffset iAlt 11 oNum_Hazards iAlt read number of hazards from worksheet Alternatives For K 1 To oNum_Hazards iAlt 1 find out which side of the baseline the hazard is on If Start Side L Then sideStart 1 Else sideStart 1 End If If End Side
129. ncrements for trajectories HM Slope of line between hazard coordinates Hy0 Lateral coordinate of hazard at longitudinal coordinate x Hy1 Lateral coordinate of hazard at longitudinal coordinate x impact_Count_NTS Non traffic side impacts on each hazard impact_Count_tot Total count of all impacts on each hazard impact_Count_TS Traffic side impacts on each hazard MaxL Maximum length of vehicle trajectory path Max_num_traj Maximum number of possible trajectory paths for the analysis MaxX Maximum x coord value for vehicle trajectory MinY Minimum y coord value for vehicle trajectory NCgrade Number of columns of data in the Slope Grade Adjustment table NChorcuv Number of columns of data in the Slope Horizontal Curvature 1 R Adjustment table NCslope Number of columns of data in the Rollover Probability table nope Number of data points used in defining trajectory paths NRgrade Number of rows of data in the Slope Grade Adjustment table NRhorcurv Number of rows of data in the Slope Horizontal Curvature 1 R Adjustment table NRslope Number of rows of data in the Rollover Probability table num_Departure_Incs Total number of departure points for a given segment num_Dir Number of directions e g Primary and or Opposing for each segment num_LDS Number of lane departure sides e g left and or right for each direction num_pre Number of data columns preceding the trajectory path i
130. nformation in the trajectory databases num_traj Number of trajectories evaluated at each increment for the current roadside segment num_traj_seg Current trajectory path number being analyzed on segment num_traj_tot Total number of trajectories evaluated for the current roadside segment num_traj5 Number of trajectory cases used in analysis num_veh Total number of vehicle types for analysis PHIgrade Table of Adjustment factors for rollover based on vertical grade C 63 PHIhorcurv Table of Adjustment factors for rollover based on horizontal curvature POC Probability of occurrence used as a weight factor for collision costs PRslope Table of baseline probability for rollover R Radius of point hazards SegLength Length of segment SegRow Row number for input of segment data on worksheet Road Segements Shift For use in identifying column position on worksheet Cross Section for input of roadside cross section data Row Row number for output to worksheet POC Scratch TrajectoryGrid Name of trajectory grid sheet for current vehicle type trajx Vehicle trajectory path x coord data Trajectory Grid trajy Vehicle trajectory path y coord data Trajectory Grid v0 Trajectory velocity data Velocity Grid VehCharac Vehicle characteristics X0 Longitudinal coordinate of current encroachment location Ymax Maximum lateral coordinate for roadside cross section in local coordinate frame C 64 Traffic Informatio
131. nt data for the development of accurate trajectory paths for motorcycles and trucks when such data becomes available however the trajectory database worksheets can be readily updated The trajectory data currently included in RSAPv3 corresponds to trajectories taken from the NCHRP 17 22 crash reconstruction database and are based on reconstructed crashes involving passenger vehicles The database is composed of 787 of the 890 crash cases collected from the FHWA rollover study NCHRP Project 17 11 and NCHRP Project 17 22 BlighO4 Mak10 Since each trajectory case in the 22 27 database is linked directly to its corresponding crash conditions and roadway and roadside characteristics it is a simple process to filter the trajectory data directly and select only the trajectory cases with roadway and roadside characteristics similar to those for the given project case This eliminates the need to have multiple layers of trajectory tables corresponding to numerous roadway and roadside conditions Select Trajectory Path Database The name of the worksheet containing the database of trajectories for each vehicle type is read from column 11 on the Traffic Information worksheet in RSAPv3 For iVeh 1 To number of vehicle types in analysis TrajectoryGrid name of trajectory worksheet Select Relevant Trajectory Paths for the Analysis RSAPv3 searches the trajectory database to identify relevant cases based on similarity to the given road segment
132. nt driven structure is enabled primarily by the frmRSAPcontrols form The last type of component in the RSAPv3 VBA project are code modules There are nine RSAPv3 code modules moduleAlternatives contains code that supports the Alternatives worksheet moduleEncroachments contains code that calculates the base encroachment rate applies adjustments and performs other tasks in support of the Road Segments worksheet moduleMain is the main program control for the analysis modulePOCanalysis contains code that performs the collision analysis modulePOChaz contains code that reads the hazard information and processes it in support of modulePOCanalysis modulePOCtraj contains code that selects grades and processes trajectories in support of modulePOCanalysis moduleResults contains code that organizes and processes the results and creates the information on the Results worksheet moduleTools contains a variety of code that acts in support of RSAPv3 but is not associated with any particular worksheet or form moduleXsection contains code that supports the X Section worksheet CONVENTIONS Each of these worksheets forms and code modules will be described in later portions of this manual The following convention has generally been used throughout the RSAPv3 code sh designates an MS Excel worksheet frm designates a VBA form btn designates a command button Ibl designates a label
133. ols Dialog box has appeared select any cell in any worksheet and press ALT F11 This starts the VBA editor which appears as another window The RSAPv3 code is password protected so double clicking the RSAPv3 entry in the Project VBA workspace will prompt for a password Once a C 7 correct password has been entered the project components are shown note the password up through RSAP 3 0 0 Beta Relese 120815 is roadsafe RSAP COMPONENTS As is typical for VBA projects there are three types of project components in RSAPv3 as follows e Microsoft Excel Objects e Forms e Modules The Microsoft Excel Objects in RSAPv3 include the following 8 visible and 10 hidden worksheets note names in parenthesis are the worksheet names that are displayed in the workbook whereas the primary name is the internal name of the worksheet generally used in the code Whether the worksheet is by default hidden is also indicated shAlternatives Alternatives shDefaults Defaults hidden shEncrAdj Encr Freq and Adj shPOCplots POC Plots hidden shPOCscratch POC Scratch hidden shPrgData Program Data hidden shPrjInfo Project Info shProfile Profile hidden shRdSegs Road Segments shRedirectionGridC Redirection Cars hidden shRedirectionGridT Redirection Trucks hidden shResults Results shSeverity Severity shTraffInfo Traffic Info shXsection Cross Section TrajectoryGrid1 TrajectoryGrid
134. on Define General Segment Characteristics For iDir PrDir to OpDir Step 2 For each traffic direction For iLDS 1to2 Step 1 For each lane departure side Roadside X Section Horizontal Curve Highway Grade Posted Speed Limit For iALT 1 to num_ALTS For each alternative Read Roadway Roadside Characteristics Compute Baseline Probability for Calisubinterpoiate Rollover for each Sideslope Compute Rollover Adjustment Factors Call subBilnterpolate For iVeh 1 to num_Veh For each vehicle type Select Trajectories For Analysis H Call ModulePOCtraj For iDP 1 to num_Departure_Incs For each departure station For iTraj 1 to num_traj For each trajectory Call ModulePOCanalysis Next iTraj Next iDP Next iVeh Next iALT Next iLDS Next iDir Next iSeg Figure 22 Flow Chart for ModulePOCMaine C 61 Input Variables oNum_Hazards Number of hazards oHzrd_Type Hazard type line area point oHzrd_Name Hazard name e g Strong Post Guardrail Concrete Median Barrier etc oHzrd_EFCCR65 EFCCR65 for hazard type oHzrd_Prent_PRV Percent Penetration Rollover Vault for hazard oHzrd_Prent_RR Percent redirection for hazard including rollover after redirection oHzrd_Capacity Energy capacity for hazard ft lb oHzrd_Height Barrier height in oHzrd_Connection Identifies LON hazard attached to
135. only one direction of traffic i e primary and two encroachment locations left side encroachments and right side encroachments Right side encroachments initiate from the edge line of the right most lane of traffic and encroach directly onto the right roadside Left side encroachments initiate from the edge line of the left most lane of traffic and encroach directly into the left roadside The lateral offset for one way roads is measured with respect to the left edge line of the roadway i N amp SS Primary Left Lateral Offset form Left Edge Line ft 24 4 amp Primary Right Departures Figure 26 Illustration of encroachment locations for a one way roadway C 71 The maximum number of roadside encroachments for each segment is defined in the program via the following procedure Divided Roadway For iSeg 1 To NOS If roadway type D Then num_LDS 2 num_Dir 2 oMedianHW shRdSegs Cells SegRow K value 2 Undivided Roadway Elself roadway type U Then num_LDS 2 num_Dir 2 oMedianHW 0 One Way Roadway Else num_LDS 2 num_Dir 1 oMedianHW 0 End If The next step in the analysis is to determine which encroachments e g Primary Right Primary Left etc to evaluate based on user selection information from the RSAPv3 Control Form In some cases only certain roadsides will be of interest in an analysis For example a highway engineer may want to know the best alternative for
136. ontal curves are defined by curve radius and by the relative direction of the curve e g positive curves to right and negative to left relative to the direction of travel Accordingly the horizontal curve radius for each crash case in the database is compared to the value for each segment using the following relationships For i 1 To Count If no value for horizontal curve was reported for a given case in the database _ Or If a value of 0 was mistakenly entered Then C 99 TrajectoryData i 16 100000 set to straight End If If departure is to the right then the curvature relative to the vehicle departure is positive If TrajectoryData i 28 R Then curvature l TrajectoryData i 16 oPDcurvature 1 0PDCR If departure is to the left then the curvature relative to the vehicle departure is negative Else curvature 1 TrajectoryData i 16 oPDcurvature 1 0PDCR End If S4score 1 1079 Abs curvature oPDcurvature The one exception is if both the oPDCR and the curve for the trajectory case are tangent i e I gt 10 000I then the score is set to 1 0 If Abs oPDcurvature lt 1 10000 And Abs curvature lt 1 10000 Then S4score 1 End If Compute Composite Score for Each Case in the Database The individual scores for each of the four criteria presented above are then combined into a single representative composite score for the trajectory case where the composite score is a weig
137. or Module POC taj jssicxcersiesghescsencceacweaies deasteccaqwa shag gadesocaatedabaatenn 94 RSAPv3 Controls Dialog Default Analysis Settings ee eeeeeeeeeee 101 Flow Chart for Module POCanalysis 0 0 0 eeeeeseceessceceseceeseeeeeeneeeenteeeeaaees 107 Flow chart for detecting collisions with line hazards in Module POCanalysis E SIS NON SPE OEE RT SCT SIR PENS PRT AE E E Pot AION PATEL 108 Flow chart for detecting collisions with point hazards in Module POE analysis scans ns Tats Daas dell E oes ap tana a Nae ete ena 109 Illustration of roadway segment showing definition Of Xo0 c eeeeeeeeeees 111 Illustration Trajectory path a crossing hazard from left side and b crossing hazard from right side 630i ecehenicyeardsazsverarencclaataoededvavnceteaseeveveaavceuatasedacs 115 C 3 Figure 39 Illustration Defining the effective radius R of a Point hazard 120 Figure 40 Illustration Trajectory path crossing a point hazard 0 ce eeeeeeseeeeeteeeeeees 121 Figure 41 Probability model for trucks rolling over longitudinal barriers 128 Figure 42 Flow chart for subroutine subrolloverM2a 0 0 ee eeeeeeeeeeeeeecneeeeeeeeneees 139 Figure 43 Flow chart for subroutine subRolloverM2D 2 0 0 eeeeeeseceesteeeestecetteeeenaees 142 Figure 44 Illustration of trajectory path intersecting two hazards c ceesceeeeseeeeeees 144 LIST OF TABLES Table 1 Lookup Table for probability o
138. orm Median Center Line ft An undivided highway as shown in Figure 25 also has two directions of traffic Primary and Opposing however there is no separation distance between the opposing lanes e g median width is zero For each direction of traffic there are again two encroachment possibilities left side encroachments and right side encroachments Right side encroachments initiate from the edge line of the right most lane of traffic with respect to the direction of traffic and encroach directly onto the roadside Left side encroachments initiate from the edge line of the left most lane of traffic with respect to the direction of traffic and encroach directly into the opposing traffic lanes Thus for undivided roadways the lateral extent of the vehicle trajectory must exceed the total width of all opposing lanes before it reaches the left roadside The lateral offset for undivided highways is measured with respect to the center line yellow line separating the two traffic directions While left encroachments depart from the centerline of the highway there is no provision in RSAPv3 for examining the probability that the vehicle will strike a vehicle in the opposing direction C 70 Opposing Right Encroachments a 24 Lateral Offset form Center Line ft 24 D Primary Right Encroachments Figure 25 Illustration of encroachment locations for an undivided roadway A one way roadway as shown in Figure 26 has
139. penetration is re initialized along with the value for the trajectory length TL used in computing the probability of rollover Do While j lt nopc And logic_2 true And v lt gt 0 And POC gt 0 001 If yj lt gt Then For K 1 To total number of hazards for the current alternative If logic_1 K true Then If oHzrd_Type iAlt K P Then If x gt oHx effective radius of hazard _ And x lt oHx effective radius of hazard _ And y lt gt Then If D lt effective radius of hazard _ And d0 K gt effective radius of hazard Then VO v v0 is reset corresponding to change in velocity after penetration TL 0 _ trajectory length is reset to correspond to the new vO End If Reset distance dO for next increment d0 K D redefine distance from previous trajectory point to hazard End If End If End If Move to the next hazard and continue evaluating current path for collisions Next K If the velocity of the current increment is zero e g due to kinetic energy expended during a penetration or redirection or the trajectory path has ended then set j nopc which will end the analysis for the current increment Do While j lt nopc And logic_2 true And v lt gt 0 And POC gt 0 001 If yj lt gt Then ElseIf v 0 Or y Then j nopc End If Loop End Sub C 123 SubCollision_Statistics This subroutine is called by ModulePOCAnalysis and the subroutines subPenetrate
140. pplication ExecuteExcel4Macro SHOW TOOLBAR Ribbon false Re start RSAP with gt StartRSAP Else Unload frmRSAPcontrols gt stops execution of RSAP Restore usual Excel display settings ActiveWindow DisplayHeadings True Application DisplayFormulaBar True Active Worksheet Unprotect shPrgData Range B6 value Application Execute Excel4Macro SHOW TOOLBAR Ribbon true End If killSplash0 This macro which is called from the Auto_Open macro simply unloads the splash screen form after it has been displayed for 5 seconds RangeisMT This macro tests a range to determine if there are any values in the range The variable testRange is passed to the macro and tested for blank values using the range method Find The procedure is Set test testRange find LookIn xlValues If test is nothing then RangeisMT FALSE Else RangeisMT TRUE End if This function is used in several subroutines to test if there is data in the specified range C 151 showRowsCols This is a useful macro for debugging The macro is a toggle much like editSeverity and editSheet The macro turns on all Excel toolbar functions makes all sheets visible and makes the row and column labels visible StartRSAP This macro was previously discussed and described in the Project Input and Control Chapter to which the reader should refer This macro is called by the Auto_Open macro but can also be executed using the key stroke C
141. presentative velocity for computing the crash costs is then computed as vavg V3avg 1 3 The program then calls the subroutine subCollision_Statistics K Haznum 1 sets the array position to rollover hazard CS TS set Colloision Side to CS for counting the number of rollovers Call subCollision_Statistics The probability that the vehicle continues on without rolling over is then computed and returned to ModulePOCanalysis POC POC POCroll The variables POCroll0 and Proll0 are computed and saved for subsequent rollover calculations POCroll0 1 POC Proll0 SumPRslopexL LT End Sub SEVERITY MODULE The severity module is interwoven with the crash prediction module since the severity of each crash predicted must be estimated The severity module is represented by the following term in the RSAP governing equation P Sev Trj N Haz There are actually relatively few severity calculations within RSAP since the database of EFCCR values serves as a measure of the severity of each likely crash As described in the last chapter when a collision is detected in the crash prediction module the EFFCR corresponding to the hazard struck and the speed of the vehicle is obtained from the Severity worksheet All the EFCCR values for each hazard interacted with along the vehicle s trajectory are summed and this summation is the EFCCR for that particular trajectory Background for developing and adding EFCCR values
142. probability of rollover is then stored in the array CSglob 4 Call subInterpolate The adjustment factors for the probability of rollover for vertical grade and horizontal curve radius is then determined using bi linear interpolation of the adjustment factor tables e g stored in arrays PHIgrade and PHIhorcurv respectively The values for the vertical grade adjustment factor and the horizontal curve adjustment factor are stored in array CSglob 5 and CSglob 6 respectively Call subBilnterpolate Call subBilnterpolate Next i Select Trajectories for Analysis The next step in the analysis is to select trajectories that are representative of the vehicle type and roadway roadside characteristics The probability of collision given that C 79 a vehicle has encroached onto the roadside or median is determined by directly projecting encroachment trajectories from reconstructed crash cases onto the roadside or median and evaluating their probability of collision with each roadside hazard Three databases of trajectories are stored on RSAPv3 worksheets TrajectoryGrid1 TrajecotryGrid2 and TrajectoryGrid3 for motorcycle trajectories passenger vehicle trajectories and truck trajectories respectively Currently all three trajectory databases are identical which assumes that encroachment paths for all vehicle types are of similar form This of course is not likely true but at the present time there is insufficie
143. probability that an crash of severity s occurs given that a crash has occurred and E CC Sevs The expected crash cost of a crash of severity s in dollars The term ADT L P Encr yields the expected number of encroachments on a segment in units of encroachments mi year ADT P Encr can be further defined as n encr ADT P Encr f base ear i 1 where the terms are as defined before and frase encr iS the base encroachment rate in units of encroachments mi yr and EAF are encroachment adjustment factors fhase encr 18 tabulated on the Encr Freq and Adj worksheet in RSAPv3 as are the encroachment modification factors EAF These values are simple lookup tables where the appropriate adjustment or base encroachment is read from the tables given the geometric and traffic characteristics of the highway provided by the user The collision and severity conditional encroachments P CrlEncr P Sevs Cr must be grouped together because each encroachment could have multiple events with different severities P CrlEncr P Sevs Cr can be expanded to l m P Cr Encr P Sev Cr 1y gt P Trjx N Haz Encr P Sev Trj N Haz k 1 j 1 Where Trjg N Haz is the probability that trajectory k will intersect hazard j and the summation is done over all hazards and all trajectories RSAPv3 will typically process tens of thousands of trajectories for each segment to arrive at this summation Each trajectory analyzed is compared to every hazard
144. r collision with each hazard For example if the hazard lies outside the extent of the trajectory path then the path is not checked for collision with the hazard The maximum length of the path is also computed for use in the determining the probability of rollover MinY iVeh i check if current path coordinate is less than the previous minimum value and keep the lesser of the two MaxY iVeh i check if current path coordinate is greater than the previous maximum value and keep the greater of the two Ifj num_pre iVeh 1 Then MaxL iVeh i trajy iVeh i j Else C 104 MaxL iVeh i compute maximum length of trajectory path End If End If Next j Next i MODULEPOCANALYSIS This module is called by ModulePOCMain to compute the probability of impact for a given trajectory case and to compute the associated crash costs The basic procedure is to 1 map the trajectory path onto the roadside or median 2 examine the trajectory point by point for collision with each hazard 3 if collision occurs compute collision cost i e call subTrajectory_Statistics check for penetration call subPenetrate and check for redirection call subRedirect 4 return cost statistics back to Module POCMain Input Variables The following are a list of variables passed from Module POCMain i trajectory path number iALT alternative number iDirection traffic direction i e 1 primary 1 opposing iDP departure poin
145. rType Non Rigid End If If the hazard type on the current row in the redirection trajectory database is equal to BarrierType then include its trajectory path in the analysis If barrier type in database BarrierType Then A constant deceleration of 12 ft s is assumed for all the redirection paths decelR 12 ft s2 Initialize the minimum and maximum extents of the redirection trajectory paths Recall that these parameters are used in ModulePOCanalysis to determine if a hazard is within reach of the path if not the path is not evaluated MinY 1000000 MaxY 1000000 Initialize starting coordinates of redirection path x0 x y0 y Read in the redirection path coordinates for the currently selected row of data and correct for local path direction relative to the hazard s local reference frame For j 1 To total number of path coordinates xL x coordinate value SignX yL y coordinate value SignY C 136 Transform from Local to Global Reference Frame The local x coordinate direction of each trajectory is co linear with the line of the hazard The following lines of code transforms the coordinates from the local reference frame to the global coordinate system for the analysis xR iVeh i j xL Cos Theta_Haz yL Sin Theta_Haz yR iVeh i j xL Sin Theta_Haz yL Cos Theta_Haz Determine minimum and maximum extent of redirection paths and determine the maximum length of the path
146. rail The program goes back and looks for hazards named end terminal It then searches the end coordinates of all line hazards to find the one that is coincident with the location of the end terminal The end terminal and the line hazard are then associated by setting oHzrd_Connection iAlt K j where iALT is the alternative containing the hazard pair K is the hazard number for the end terminal and j is the hazard number for the line hazard If a mate cannot be found RSAPv3 will terminate the analysis then place the cursor on the alternative worksheet in the data cell corresponding to the end terminal and show a pop up window with the message Guardrail terminal not connected to guardrail The coordinates will have to be corrected on the Alternative sheet and the analysis restarted For K 1 To oNum_Hazards iAlt If oHzrd_GenType iAlt K TerminalEnds Then oHzrd_Connection iAlt K 0 initialize association to 0 For j 1 To oNum_Hazards iAlt If oHzrd_Type iAlt j L Then If oHx of end terminal oHx or oHx2 of line hazard _ And _ oHy of end terminal oHy or oHy gt of line hazard _ Then oHzrd_Connection iAlt K j C 92 End If End If Next j If oHzrd_Connection iAlt K 0 Then shAlternatives Select Cells HazRow K 1 AltOffset 8 Select MsgBox Guardrail terminal not connected to Guardrail End End If End If Next K Next iAlt End Sub MODULEPOCTRAJ This mod
147. rees the task can also be achieved by simply resorting the data in descending order for Primary Left and Opposing Right encroachments i e iDir iLDS 1 Itis also necessary to resort the data for Primary Right and Opposing Left encroachments i e iDir iLDS 1 in order to guard against data being input out of order and to eliminate any data with null values For example the worksheet provides the option of using up to eight data points to define a cross section profile In most cases however only a few data points will be necessary to completely define the roadside in which case many of the data cells in the worksheet will have no data If iDir iLDS 1 Then Call MatrixSort and sort cross section coordinates in ascending order with respect to local reference frame If iDir iLDS 1 Then C 75 Call MatrixSort and sort cross section coordinates in descending order with respect to local reference frame The next step is to determine starting lateral coordinate for roadside cross section corresponding to the edge of the roadway at the point of encroachment This point CSy0 0 represents the origin for the local coordinate system of the roadside cross section oRoadWPR Primary road width read from worksheet Road Segments oRoadWOP Opposing road width read from worksheet Road Segments If hwyType Divided If Encroachment Side Primary Right Then CSy0 oMedianHW oRoadWPR iDir If Encroac
148. rement of each trajectory path As the encroachment continues the likelihood of rollover increases So the probability of a collision at Point B is dependent on the vehicle getting to Point B without rolling over first The crash cost of an impact at Point B is computed based on impact conditions and the severity rating of the hazard Then the average expected cost of the collision is determined by multiplying the baseline crash cost by its probability of occurrence POC Likewise for the encroachment to result in a second collision at Point E a sequence of three specific events must happen 1 the vehicle must get to Point B without rolling over 2 the vehicle must penetrate or vault the line hazard Point D and 3 the vehicle must then get to Point E without rolling over or stopping first Thus the probability of collision for each possible collision in the sequence of events continuously reduces with each collision So even though the severity rating for the hazard at Point E may be very high the average crash cost on the hazard will be reduced according to the likelihood of the sequence A B D E occurring Line Hazard Point Hazard Figure 29 Illustration of a possible sequence of crash events for a given trajectory scenario The variables num_traj_seg and EFCCRi are used to compute percentile costs for each segment where num_traj_seg is a running count of the total number of trajectories being evaluated for each segment and EF
149. rier and does not roll over the barrier during redirection and does not rollover after redirection then final possibility is that the vehicle exited from the hazard and its exit trajectory will have to be evaluated for possible secondary collisions As mentioned previously redirection is not considered for Point hazards or for motorcycles If vehicle type motorcycle Then WR 0 Else WR 1 WP WRV WRR End If Compute Effective Probability Statistics and Pass Back to Parent Module The final step of this subroutine is to compute the effective probability of redirection and penetration which will be passed back to ModulePOCanalysis for use in evaluating secondary collisions For example the effective probability of redirection is computed as the probability of redirection given the current collision conditions times the probability of the impact occurring Probability of Redirection POR WR POC Probability of Rollover after Redirection PORV WRV POC Probability of Penetration POC WP POC count_pene_PRVcapacity K cumulative capacity penetrations for hazard K count_pene_rollvault K cumulative penetrations of hazard K from rollover vault SubRedirect This subroutine is called by ModulePOCAnalysis to determine redirection paths to be evaluated for subsequent impacts after redirection from the current hazard The redirection path is influenced by many factors including impact angle impact speed C 131
150. rmRSAPcontrols mpControls value 2 ROAD SEGMENTS WORKSHEET The Road Segments worksheet is used to collect information from the user about the characteristics of the roadway as shown in Figure 7 and Figure 8 The rose colored cells may be changed by the user but initially contain RSAP default values the yellow cells require user input Selecting the Highway tab in the RSAP Controls Dialog or selecting the Road Segments worksheet tab will set the frmRSAPcontrols mpControls Value property to 2 display the context sensitive buttons as shown in Figure 9 activate the Road Segments worksheet i e shRdSegs The initial worksheet view will be similar to Figure 7 The Road Segments view of RSAP Controls shown in Figure 9Figure 4 includes ten command buttons which will be described below The user can either select buttons on the RSAP control form or select a yellow or rose user input cell on the worksheet in order to enter information The Road Segments worksheet has two input areas The first is the Whole Roadway Characteristics area at the top of the worksheet 1 e shRdSegs Range E3 E8 and the second is the User Entered Characteristics area in shRdSegs Range A98 D587 The user is taken to the User Entered Characteristics area when the Enter Highway Characteristics button is selected C 21 Insert Page Layout ormulas Data E3 Fe 50 Concrete Barrier Example Problem WHOLE ROADWAY CHARACTERISTICS PERCEN
151. rmine Probability of Penetration Rollover Barrier and Vault The subroutine subPenetrate is called to compute the probability of penetration due to exceeding structural capacity of the barrier rolling over the barrier and vaulting the barrier Along with the crash statistics e g probability of penetration probability of redirection etc the subroutine also passes back the updated velocity which is reduced C 118 according to the amount of energy expended in penetrating the barrier The subroutines are presented in a later section of this Manual and the details of determining penetration are presented in the ENGINEER S MANUAL Call subPenetrate VO v TL 0 _ trajectory length is reset to correspond to the new vO 4 Evaluate Redirection Paths for Secondary Collisions When a collision occurs with a line hazard there is generally a probability of redirection some exceptions would be a tree line hazard or a water hazard For longitudinal barriers in particular the probability of redirection is dependent upon the type of vehicle and whether or not the vehicle penetrated the barrier Impacts with motorcycles are not evaluated for redirection since it is likely that the passengers would have been ejected upon impact Penetration is determined using a combination of crash statistics and the mechanics of the impact event which are discussed in detail in the ENGINEER S MANUAL If the probability of redirection is greater 1 percent and
152. rom the user like a project name the design life rate of return construction year etc as shown in Figure 3 Note Figure 3 like other screen shots of the worksheet in this manual shows the worksheets with the row and column labels on This is not the normal RSAP default but they are shown that way in this manual to aid in referring to the cell locations in the text The only required information is the project name in cell B5 indicated in yellow in Figure 3 The rose colored cells may be changed by the user but contain RSAP default values Selecting the Project tab in the RSAP Controls Dialog or selecting the Program Information worksheet tab will set the frmRSAPcontrols mpControls Value property to 0 display the context sensitive buttons as shown in Figure 4 and activate the Project Information worksheet i e shPrjInfo The Project Information view of RSAP Controls shown in Figure 4 includes five command buttons which will be described below The user can either select button on the RSAP control form or select a yellow or rose user input cell on the worksheet in order to enter information Activate Method Selecting the Project tab on the RSAP Dialog Controls or the Project Information tab in the Excel worksheet tabs instantiates the shPrjInfo Worksheet_Activate method In the case of shPrjInfo RSAP simply checks to see if there is any input in cell B5 i e the project name This is the
153. rt is contained in columns L Z so this macro simply un hides columns L Z and hides columns A K and AA AI The resulting view is shown in Figure 16 C 42 btnBCReport_ClickQ The Benefit Cost Report and Table are contained in columns AA AI so this macro makes those columns visible and hides columns A K and L Z The resulting view is shown in Figure 17 btnFeatureReport_Click The Feature Report is the default view shown on the Results worksheet and this button returns the view to that report It simply makes columns A K visible and hides columns L AI The resulting view is shown in Figure 15 btnPrint_ClickQ This macro first unprotects shResults and call the macro moduleResults printReports which will be described in the Benefit Cost Module Chapter SETTINGS Unlike most of the tabs on the RSAP Controls Dialog the Settings tab is not associated with a particular worksheet so whatever worksheet is active when the Setting tab is selected remains active and in view The Settings tab provides some useful tools for the user to control the display and functionality of RSAP and has no impact on the analysis results Selecting the Settings tab in the RSAP Controls Dialog will set the frmRSAPcontrols mpControls Value property to 7 display the context sensitive buttons as shown in Figure 19 The Settings view of RSAP Controls shown in Figure 19 includes three visible command buttons one of which is a toggle which will be described
154. s dependent on approach path of the vehicle For example Figure 28 shows a median cross section with a vehicle encroaching from the left In this scenario the vehicle would be going down hill on the left slope and up hill on the right slope thus the slope of the terrain is effectively negative on the left and positive on the right for this encroachment condition On the other hand when a vehicle encroaches onto the median from the right side the vehicle would be going down hill on the right slope and up hill on the left slope in which case the slope of the terrain would effectively be negative on the right and positive on the left C 77 Negative Slope Positive Slope a Left Encroachment Positive Slope Negative Slope b Right Encroachment Figure 28 Illustration of apparent sign of roadside slope relative to encroachment path of vehicle The next step is to define the lateral coordinate of the encroachment point i e y0 for the current trajectory path in the global reference frame Recall that for divided roadways the origin of the global coordinate system is the center of the median for undivided roadways the global origin is at center of the yellow line s separating the opposing traffic lanes and for one way roadways the origin is at the left edge of the roadway The following lines of code define the lateral coordinate of the encroachment point based on departure side ILDS and direction iDir If hwyType
155. s Dialog will set the frmRSAPcontrols mpControls Value property to 6 and display the context sensitive buttons as shown in X and Y RSAP Controls btnRun_Click btnSeeTrajSettings_ Click btnPrev_Click Figure 14 RSAP Controls Dialog Analyze Condensed View btnRun_Click The Run button initiates the RSAPv3 analysis phase The macro proceeds as follows Screen updating is turned off Display status bar is turned off moduleXsection finalXsectionWrite is called to write final roadside terrain data shPOCscratch is unhidden and unprotected shPOCplots is unhidden and unprotected Load frmProgressBar Start timer Call ModuleMain Main End timer Unload frmProgressBar If user has not canceled the run then Activate the Results worksheet Set mpControls 6 to make the RSAP Controls Results Dialog visible Print the analysis time information on the Results worksheet Call moduleResults FeatureResults Call moduleResults SegResults Else Set mpControls 5 the Analyze tab Exit Sub End if The call to moduleMain Main initiates the collision and severity modules of RSAP and are discussed in the Crash Prediction Module and Severity Module chapters The calls to moduleResults featureResults and moduleResults segResults initiates the Benefit Cost Module as discussed in the Benefit Cost Module Chapter btnSeeTrajSettings_Click Selecting the See Settings button makes the full settings button panel visible as shown in
156. s that are used as development and maintenance tools These macros are not normally needed by the user but are useful when adding lookup tables debugging and other software maintenance tasks Auto_Open This macro was previously discussed and described in the Project Input and Control Chapter to which the reader should refer This macro unloads any currently running forms to avoid conflicts hides the Excel toolbars loads the splash screen for 5 seconds and then unloads it The macro then calls the macro StartRSAP which starts the RSAP execution C 149 editSeverities This macro is a toggle macro that is turned on and off by selecting the key stroke CTRL SHIFT H The first toggle stops the execution of RSAP and puts Excel into a conventional editing model The second toggle removed the standard Excel ribbons re protects the worksheet and restarts RSAP The second toggle also rebuilds the hazard menusm on shPrgData The procedure is as follows Select the Severity Worksheet Detect the mode by whether the display headings are on or off If ActiveWindow DisplayHeadings True Then gt turn off edit mode and re start Count number of rows in shSeverity botRow Count 1 Sort the hazard data into hazard category order Copy hazard names to the Program Data worksheet Reset the data range names on shPrgData using Active Workbook Names Set the display back to usual RSAP mode shSeverity Select Active Window DisplayHeadings False Application
157. sed on the road characteristics written by segChars range A71 P90 Program Variables spdLim the posted speed limit numLane the total number of lanes p_grade the grade in the primary direction p_hcurv radius of horizontal curvature in the primary direction numLanePrim number of lanes in the primary direction Inwidth lane width access access density rumble Boolean value indicating presence absence of edge line rumble strips hwyType character indicating the highway type e D for divided highways e U for undivided highways and e O for one way roads and ramps Terrain character indicating the general terrain type e F for flat e R for rolling and e M for mountainous Seg segment number Procedure adjustEncr proceeds by reading in the highway characteristics from shRdSegs performing some error checking appropriate to each characteristics and then looking up the appropriate adjustment factor on shEncrAdj using the adjust function The subroutine has logic to account for the directionality of some of the adjustments For example the grade in the primary direction is used to find the adjustment in the opposing direction by taking the negative If the primary grade is 2 percent then the opposing grade must be 2 percent Similarly if the total number of lanes are known and the number of lanes in the primary direction are known the number of lanes in the opposing direction can be calc
158. so defined on the RSAPv3 Control Form shown in Figure 33 It was determined that the roadside cross section has a greater influence on the vehicle s trajectory path than the other roadway and roadside characteristics and was therefore assigned a higher weight in the calculation of the composite score Likewise the horizontal alignment of the roadway was also considered to have a significant effect on trajectory path and was assigned a relatively higher weight as well The default value of the weight assigned to each criterion is listed below Refer to the ENGINEER S MANUAL for further discussion regarding these values W 3 weight assigned to roadside cross section W gt 2 weight assigned to horizontal curvature W3 1 weight assigned to vertical grade Wz 1 weight assigned to posted speed The following lines of code read the weight values from the RSAPv3 Control Form compute the composite score for the i trajectory case and store the score values in the array Trajscore WS1 CDbl frmRSAPcontrols Read weight for cross section slope profile WS2 Read weight for posted speed WS3 Read weight for vertical grade WS4 Read weight for horizontal curve radius Trajscore i 1 1 Trajscore i 2 WSI SIscore WS2 S2score WS3 S3score _ WS4 S4score WSI WS2 WS3 WS4 Trajscore i 3 SI score Trajscore i 4 S2score Trajscore i 5 S3score Trajscore i 6 S4score Next
159. stment factors The details of each of these subroutines is discussed below adjust This function is a linear interpolation lookup function that takes the segment characteristic to find the appropriate adjustment value based on the characteristic value and the highway type Input Variables The following five variables are passed to the subroutine e inSheetis e startCell is the top left cell in the adjustment factor lookup table being queried The legal values of startCell in this version of RSAP are o A5 or the base encroachment frequency E5 for the access density adjustment factor I5 for the rumble strip adjustment factor MS for the multi lane adjustment factor Q5 for the posted speed limit adjustment factor Y5 for the shoulder width adjustment factor ACS for the terrain type adjustment factor AGS for the grade adjustment factor and 000000 0 C 50 o AKS for the horizontal curvature adjustment factor e shift corresponds to the number of columns to the left of the first column of the queried lookup table and represents the highway type Shift can have one of the following values o l for divided highways o 2 for undivided highways and o 3 for one way roadways Any other value returns an error e lookUpVal is the value of the particular characteristic that is being adjusted For example if the adjustment factor for Lane Width is being sought JookUpVal might be 12 feet e debugFlag is a Boolean indicator th
160. t to allow for user input The Segment and Clear buttons are made visible and the Recalculate Encroachments Edit Whole Project Info and Defaults buttons are hidden The view is split showing the Whole Project Characteristics on the top and the user data entry area on the bottom Control shifts to the user to allow for data entry and remains there until the user selects Segment Project btnSeeEncr_Click This macro simply repositions the view of shRdSegs such that the Expected EncroachmentsTable i e shRdSegs Range A11 J33 is in view btnDefaults_Click This macro clears all information from the rose colored cells and copies the RSAP default values from shDefaults btnEditWholePrjInf_ClickQ This macro sets up the view so that the Whole Project Information is visible and the styles are set to allow user input btnEncr_Click This button calls the macros that calculate the encroachments and adjustments on each segment of the roadway The macro first checks to be sure there is appropriate data in the Road Characteristics Table If there appears to be missing data the user is notified and the macro is exited If there is sufficient data the macros moduleEncroachments calcBaseEncr and moduleEncroachment adjustEncr are called These macros are described in the next chapter Encroachment Module btnSegment_Click This button is initially hidden but is made visible when the Enter Road Characteris
161. t iLDS encroachment side 1 right 1 left iSeg segment number iVeh vehicle type number grid_inc longitudinal increments of trajectory path oHzrd_Name Name of hazard oHzrd_GenType oHzrd_Type oHzrd_EFCCR65 oHzrd_Prent_PRV oHzrd_Prent_RR oHzrd_Capacity oHzrd_Height oHzrd_Connection Identifies LON hazard attached to END TERMINAL oPDCR horizontal curve radius oPDG roadway vertical grade oPSL posted speed limit SheetName name of the worksheet containing the database of reconstructed trajectories C 105 e num_veh total number of vehicle types e ymaxp maximum extent of cross section profile in local coordinates Program Variables The following are a list of variables defined in the Module e POC probability of collision C 106 Initialize variables No Return to POCMain Yes Do While j lt number of trajectory points And velocity gt zero And POC gt 0 001 Increment forward delta x Compute velocity Compute trajectory length Redi trajecto yn Compute probability of rollover ry Yes For K 1 to number of hazards For each hazard If Hazard Type Line Check for Impact see flaw chart of procedure te identify impacts with Line hazards If Hazard Type Point Check for Impact see flow chart of procedure to identify impacts with Point hazards Figure 34 Flow Chart for Module POCanal
162. t View eccceeeseceesseeeesteeeeneeees 40 RSAP Controls Dialog Results 00 0 ee eecccseececsecceesscceesscceeseceeenseeeseeeees 42 RSAP Controls Dialog Setunes 2 oi we es ee PA eee 44 SEveity Worksheet sie sccavsvecdasecesiedcassbacadedaydaccissside peungedacaseadaacsanbdedeangeoeateaeseaes 46 RSAP Controls Dialog Hazards cceeecceessecesneceeececeeneeceeeneeeseeeeeseeeees 47 Plow Chart for ModulePOC Maine c 33 c0sc4 ccd os eactecsigriacsad eanasteensie arcana cave 61 RSAP Controls Dialog Analyze Expanded View Showing Settings 69 Illustration of encroachment locations for a divided roadway scee8 70 Illustration of encroachment locations for an undivided roadway 71 Illustration of encroachment locations for a one way roadway see 71 Illustration of transforming the median cross section coordinates from the global reference frame to the local reference frame eeeceeeeeeeeeees 74 Illustration of apparent sign of roadside slope relative to encroachment path ODE LCN oases or ica nc a ec ae Desa ds eT cages es ay ee 78 Illustration of a possible sequence of crash events for a given trajectory SCS ADL Oct crore nie ec tas sacle one seh nar Gael Dire aed ote ry actual ed Ol pede 83 Flow chart for Modul POChaz 2 2iigscsch nid uae tdgiuh ied 88 Sketch of line hazard dimensions eseeeseceseceseeeeseecsneceseesseeesneecsaeenseensees 91 Flow chart f
163. t roadway segment and terrain alternative including all roadsides roadways and road shoulders and then uses this information to determine the baseline probability of rollover corresponding as a function of slope vertical grade and horizontal curve radius This information is later used in the probability of collision analysis In particular each trajectory path is monitored at every increment during the analysis and its position is continuously cross checked against the terrain profile to determine the probability of rollover Determine Cross Section Coordinates and Slope The first step of this task is to read in all roadside cross section coordinates from the RSAPv3 worksheet named Profiles and store them in the array variable CSglob For i 1 To 8 3 eight columns of data for each possible roadside primary roadside opposing roadside and median CSglob countx 1 y coord of X section CSglob countx 2 z coord of X section Next i The next step is to sort all the coordinates in ascending order with respect to the lateral offset coordinate values in order to guard against data being input out of order and to eliminate any data with null values The slope between each breakpoint is then computed and stored as part of the CSglob array for quick access during the analysis Call ModulePOCtraj MatrixSort CSglob countX ascend 3 1 The apparent direction of the slope i e up hill or down hill slope i
164. tart RSAP actually starts the RSAP run as follows e Sets up the application display to the RSAP default style e ProcessPrioritySet High set the process priority to high so RSAP fall into the background processes e Load frmRSAPcontrols this starts the RSAP Control Dialog box e Select shPrjInfo as the starting place for input When moduleTools StartRSAP completes the application screen should look like Figure 1 If for any reason the RSAP controls dialog disappears RSAPv3 can be re started manually with the keystroke CTRL s which is a keystroke macro that simply re runs moduleTools StartRSAP No information on the worksheets is lost when selecting CTRL S but any settings in the RSAP Controls Dialog box are re set to their default values 5 0 0 x a RSAPv3_120813_culvert RSAP PROJECT INFORMATION rg u lly 4 L Crash Cost Timeline see http www gooaccess gov usbudget fy09 hist html 2003 2024 5 2037 _ Cost used 6 000 000 B 6 749 184 6 749 184 6 749 183 f Szabat and Knapp Treatment of the Economic Value of a Statistical Life in Departmental Analyses 2009 Annual Revision U S DOT March 18 2009 see http regs dot gov M Project Information Traffic Information _ Road Segments _ Aktematves _ Severty _ Cross Section Ener Freq and Ad lt 4 An Figure 1 Initial RSAPv3 Application Display PROJECT INPUT AND CONTROL RSAP CONTROLS DIALOG BOX T
165. te of return value in cell X7 Similarly column X reads the maintenance cost for each alternative from the Alternative worksheet The Benefit Cost Report contains numerous formulae in the worksheet but discussion of these is deferred until the Benefit Cost Module Chapter below Activate Method Selecting the Results tab on the RSAP Dialog Controls or the Results tab in the Excel worksheet tabs instantiates the shResults Activate method Columns A K L AI and AL AR are initially hidden in order to display the Features Report as the default The value of mpControls is set to 6 which displays the buttons shown in Figure 18 The window is also scrolled to column A and row 1 for the initial view The macros that actually calculate the crash costs are executed after the crash prediction module is complete The two macros moduleResults featureResults and moduleResults segResults are called at the end of the btnRun macro discussed in the Analysis section C 41 btnNextSegments Figure 18 RSAP Controls Dialog Results Change Method Whenever a value on the Results worksheet is changed the shResults Change method is activated The method only looks for changes in cells X5 and X6 which contain the rate of return and design life values If either of these are changed the subroutine modulesResults and segResults are re run to recalculate the economic costs in the Segment Report btnSegReport_Click The Segment Repo
166. the score for every 5 mph difference between the posted speed limit of the segment and the value in the i trajectory case from the database Compute Vertical Grade Score The scoring criteria for vertical grade is based on the assumption that slight differences in vertical grade would have less influence on trajectory characteristics for cases of flat and uphill grades than it would for downhill grades Accordingly the vertical grade for each crash case in the database is compared to the value for each segment using the following relationships For i 1 To Count If no vertical grade was reported for a given case in the database Then TrajectoryData i 21 0 set grade to flat End If If oPDG gt 2 Then S3score 0 02392 Abs TrajectoryData i 21 oPDG 2 0 0257 Abs TrajectoryData i 21 oPDG 1 ElseIf oPDG gt 10 And oPDG lt 2 Then S3score 0 2 Abs TrajectoryData i 21 oPDG 1 Else S3score 0 1 Abs TrajectoryData i 21 oPDG 1 End If Compute Horizontal Curve Score The criteria for the similarity score for horizontal curve radii 4score is based on the absolute difference between the reciprocal of the curve radius of each segment in the project i e curvature and the reciprocal of the curve radius for i trajectory from database This value is then multiplied by a factor of 1 079 which converts the score to the same scoring scale used in the previous scoring criteria Horiz
167. tics button is pressed The style of the input area i e shRdSegs Range A98 B587 is changed to Normal 2 to prevent further use input and the Road Characteristics Table i e shRdSegs Range B71 C90 G71 V90 is cleared to prepare it for new data The macro sortRoadChars is then called to sort the characteristics into homogeneous segments and then segChars macro is called to assign the segment characteristics to the Road Characteristics Table Lastly RSAP calls the btnEncr_Click macro which calculates the base encroachment and applies the appropriate adjustments Essentially this button executes the encroachment module of RSAP as described in the next chapter After the adjusted encroachments have been calculated the macro re sets the buttons to the view shown in Figure 9 C 25 btnSeeCharTable_Click This button simply shifts the view of shRdSegs such that the Roadway Characteristics Table is in view The screen is split showing the Whole Project Information on the top and the Road Characteristics Table on the bottom btnClear_Click This button clears all the user entered information on shRdSegs ALTERNATIVES WORKSHEET The Alternatives worksheet is used to collect information from the user about the the various specific roadside alternatives that will be considered in the benefit cost analysis The alternative information is entered by the user on the Alternative worksheet i e shAlternatives as shown in Figure 1
168. to the probability of rollover on terrain slopes These tables are listed on the Encr Freq and Adj worksheet under the headings Rollover Prob Slope Grade Adjustment and Slope Horizontal Curvature 1 R Adjustment as shown in Table 1 Table 2 and Table 3 respectively C 66 Table 1 Lookup Table for probability of rollover as a function of roadside slope AO AP Rollover Prob 1 w N Table 1 provides the baseline probability of rollover for straight level roadways with speed limit of 50 mph and constant roadside slopes The left column in the table is the roadside slope and the right column is the corresponding probability of rollover The program reads this table by calling the subroutine subRollInput Call subRollInput PRslope NRslope NCslope Rollover Prob The input to subroutine subRollInput is simply the name of the table heading under which the data is found in worksheet Encr Freq and Adj The subroutine then searches the table headings in worksheet Encr Freq and Adj for the name Rollover Prob It then determines how many columns of data are in the table e g there are two columns of data in Table 1 The data in the table is read one row at a time until a blank row is found The data that is read from the worksheet is stored in the variable array name PRslope which is passed back to the main program The routine is programed this way to facilitate changes an
169. to the Severity worksheet database are described in the Engineer s Manual C 145 BENEFIT COST MODULE When conducting a benefit cost analysis a benefit cost ratio B C for each feasible alternative with benefits in the numerator and agency costs in the denominator Project benefits in this case are defined as a reduction in crash costs Project costs include the design construction and maintenance costs associated with the improvement as well as repairs required due to crashes predicted on the segment RSAPv3 determines the crash costs of each user entered roadside design alternative as described in the previous chapters The results of the final module are converted to a monetary unit of measure for direct comparison with project costs The B C ratio therefore is unitless The benefit cost ratio BCR is defined as follows CCi CC BCRy DCj DCi Where BCR j Incremental BCR of alternative j with respect to Alternative i CC CC Annualized crash cost for Alternatives i and j DC DC Annualized direct cost for Alternatives 1 and j For each alternative an average annual crash cost is calculated by summing the expected crash costs for the predicted crashes Theses crash costs are then normalized to an annual basis Any direct costs as defined by the user i e initial installation and annual maintenance are also normalized using the project life and the discount rate to an annualized basis and the BCR is ca
170. total number of selected trajectories MinY iVeh i 1000000 MaxY iVeh i 1000000 C 103 For j 1 To num_pre iVeh 300 The longitudinal path coordinates are not explicitly defined in the database instead the lateral trajectory path coordinates are defined at specified longitudinal increments equal to grid_x The following line of code determines the x coordinate of the of trajectory path based on the increment value grid_x and the number of data columns preceding the trajectory path coordinates i e num_pre The value of trajx starts at zero when j num_pre trajx iVeh i j j 1 num_pre iVeh grid_inc iVeh iDirection The next lines of code read in and define the trajectory coordinates The lateral coordinate data is preceded by various other trajectory data which are read from the trajectory database and stored in the variable array traj_y The lateral coordinates are then transformed from local to global reference frame i e they are multiplied by iDirection and iLDS Ifj lt num_pre iVeh Then trajy iVeh i j read crash cases data preceding path _ coordinates Elself TrajectoryData Trajscore i 1 j Then trajy iVeh i j Blank cells remain blank Else trajy iVeh i j read coordinate data iDirection iLDS The minimum and maximum lateral extents of the trajectory paths are also computed for use later in the analysis in deciding if a trajectory path will be assessed fo
171. ts trajectory path N 1 P R P R slope Ps sync Li tot l Where P R Probability of rollover for the trajectory P R slope Probability of rollover based on the sideslope at increment i Psa Adjustment factor for vertical grade and sideslope at increment i s uc Adjustment factor for hor curve radius and sideslope at increment i Li Length of current increment Ltot Total length of the trajectory path N Total number of increments along trajectory path during analysis The program calls subroutine subRolloverM2a to update the values in the rollover equation at each increment If the current increment is the last increment of the trajectory path then the program calls subroutine subrolloverM2b to compute the probability of rollover and the associated crash cost The subroutines are presented in a later section of this Manual and the details of the rollover model are provided in the ENGINEER S MANUAL Do While j lt nopc And logic_2 true And v lt gt 0 And POC gt 0 001 C 113 If redir_flag lt gt 1 Then N N 1 number of increments in rollover count Call subRolloverM2a If the current increment is the end of trajectory and probability of occurrence is greater than 0 1 then compute probability of rollover If j nopc Or traj iVeh i j num_pre 1 Or v 0 And POC gt 0 001 Then Call subRolloverM2b When a rollover event has been determined the statistical variables m
172. ue ii st iXsect 0 C 97 set lateral extent beyond known data to a very large number to make sure yy j can never be greater than this value yt iXsect 1000000 For j 1 To ymaxp delta_y YY yy j 1 delta_y if y gt y0 then a slope change occurs between these two positions If yy j gt yt ii Then zz j st ii 1 yy j yt ii zt ii ii ii 1 Else zz j st ii delta_y zz j 1 End If SumErrSq z j zz j 2 SumErrSq Next j The roadside cross section for each crash case in the trajectory database is compared directly to that of roadway being analyzed and is given a score which represents its degree of similarity The similarity score S score is calculated based on the square root of the sum of the residual errors squared divided by the total width of the roadside cross section as defined below For i To Count SIscore 1 SumErrSq 0 5 ymaxp Compute Post Speed Limit Score The posted speed limit for each case in the trajectory database is then compared with the posted speed limit of the current road segment and a similarity score is determined based on the following relationship For i 1 To Count If no speed limit was reported for a given case in the trajectory database Then TrajectoryData i 7 55 Set value to 55 mph End If S2score 1 Abs oPSL TrajectoryData i 7 50 C 98 The above calculation for S2score basically deducts 0 1 point from
173. ulated and the appropriate adjustment found shRdSegs Range A71 Select Do Until Selection value seg Selection value Work through the encroachments adjustments segment by segment spdLim Selection offset 0 4 value gt column 5 C 52 numLane Selection offset 0 6 value gt column 7 p_grade Selection offset 0 7 value gt column 8 p_hcurv Selection offset 0 8 value gt column 9 Protect against characters in the field If LCase p_hcurv t Then p_hcurv 9999 End If Protect against large radii curves If Abs p_hcurv gt 9999 Then p_hcurv p_hcurv Abs p_hcurv 9999 End If numLanePrim Selection offset 0 9 value gt column 10 shldrWidth Selection Offset 0 18 Value gt column 19 Inwidth Selection offset 0 12 value gt column 13 access Selection offset 0 13 value gt column 14 rumble Selection offset 0 14 value gt column 15 hwyType shRdSegs Range E5 value terrain shRdSegs Range E6 value check to be sure terrain value is legal If LCase terrain flat Or LCase terrain f Then terrain F Elself LCase terrain mountainous Or LCase terrain m Then terrain M Elself LCase terrain rolling Or LCase terrain r Then terrain R Else gt invalid terrain set terrain F and notify user End If shRdSegs Range E6 value terrain Col 2 Undivided highway data is offset 1 Divided highway data is offset 2 One way highw
174. ule is called by ModulePOCmain to select trajectories from the crash reconstruction database trajectory database to be used in the analysis The primary function of this module is search the database to identify relevant cases based on similarity to the given road segment characteristics that is the program selects all trajectory cases that have characteristics which fall within a specified range of those defined for the given project The selection methodology involves examining and scoring each individual trajectory case based on a quantitative comparison of the four critical roadway characteristics 1 e Roadside cross section profile Horizontal curve radius Highway vertical grade and Posted speed limit to those in the current project section The individual scores for each of the four criteria are then combined into a single representative composite score for the trajectory case After all trajectories have been assigned a score RSAPv3 then selects the trajectories with the highest scores for use in the analysis Figure 32 shows the flow chart for this program module The following sections discus the various programming tasks Additional information on the methodology for trajectory selection is provided in the ENGINEER S MANUAL C 93 Module POCtraj Resample cross section coordinates for current Worksheet SheetName project road side Resample cross section profile for each trajectory case
175. ust be re initialized SumV2 0 V2avg 0 N 0 End If End If Check for Collision with Hazards At each increment of the trajectory the coordinates of the path are checked to determine if they have encountered any of the hazards If however it was predetermined that the hazard is not located within the extents of the trajectory path then the evaluation for that hazard is skipped Do While j lt nopc And logic_2 true And v lt gt 0 And POC gt 0 001 If yj lt gt Then For K 1 To total number of hazards for the current alternative If logic_1 K true Then Line Hazards The basic procedure for identifying impact with line hazards is to compare the lateral coordinate of the trajectory at the current and previous increment with the corresponding lateral coordinates of the hazard If the trajectory path at the previous increment j 1 is on the left side of the hazard and the path at the current increment J is on the right side of the hazard then the hazard was struck from the left side as illustrated in Figure 38 a Likewise if the trajectory path at the previous increment j 1 is on the right side of the hazard and the path at the current increment j is on the left side of the hazard then the hazard was struck from the right side as illustrated in Figure 38 b C 114 Line Hazard a Impact on left side of hazard increment j b Impact on right side of hazard Figure 38 Illustration
176. y of a collision given an encroachment Instead a deterministic method is used where a sample of real crash trajectories are compared to the roadside and used to perform the double summation in the equation above Documented below in four main chapters are the encroachment probability module crash prediction module severity prediction module and the Benefit Cost module as implemented in RSAPv3 Each chapter documents the program architechture and structure for each of the modules This document mirrors the structure of the USER S MANUAL and ENGINEER S MANUAL to the extent possible Each manual takes the same general form and references have been made to other manuals to avoid duplication across manuals ARCHITECHTURE BACKGROUND RSAPv3 is written as a series of Visual Basic for Applications VBA macros within Microsoft Excel The Excel worksheets are used to provide a data entry location for the users as well as to provide project documentation and results to the user The macros provide user control and input forms and perform the numerous analysis tasks in the background RSAPv3 was written using VBA 7 0 running under Excel version 14 0 and Microsoft Windows NT 6 01 i e Windows 7 Professional Service Pack 1 RSAPv3 is backwardly compatible with Excel 12 and has been tested with Windows NT XP and 2007 To access the VBA code start any macro enabled RSAP workbook or template After the splash screen has disappeared and the RSAP Contr
177. ysis C 107 Module POCAnalysis For K 1 to number of hazards if Hazard Type LINE and end_pen_flag lt gt k Then Check for collision No extents If Yi SYhazara aNd Y1 gt Yhazard Then Collision TRUE if lateral extent of trajectory is less than or equal to lateral position of hazard at current incrementand is greater than lateral position at next increment then collision occurs with left side of hazard Collect Collision subCollision Statistics Initialize Rollover Variables Determine Impact Side Traffic or Non Traffic Side Else If 2 jazard ANd Yyy lt Yhazard Then Collision TRUE ff lateral extent of trajectory is greater than or equal to lateral position of hazard at current increment and is fess than lateral position at next increment then collision occurs with right side of hazard Compute Impact Angle Determine Probability of Penetration Call subPenetrate Evaluate Redirection Paths Call subRedirect Figure 35 Flow chart for detecting collisions with line hazards in Module POCanalysis C 108 Module POCAnalysis For K 1 to number of hazards if Hazard Type LINE and end_pen_flag lt gt k Then Check for collision ae if YS Yhazard and Yp1 gt Yhazard Then Collision TRUE if lateral extent of trajectory is less than or equ
178. zard o traffic side impact on left side of road CSRL right side of hazard Where CSRL is an acronym for Collision Side Right or Left If CSRL left Then SignY 1 Else SignY 1 End If If the impact angle is greater than 90 degrees then the x coordinate of the redirection path in the local reference frame i e relative to the hazard changes sign If Abs Theta gt 90 3 14159 180 Then SignX 1 Else SignX 1 End If Determine total number of redirection paths to be used in analysis MyrowR 4 first row with path data Do Until there are no more rows of data If hazard general type BridgeRails _ Or hazard general type Guardrails_Rigid _ Or hazard general type MedianBarriers_Rigid Then BarrierType Rigid Else BarrierType Non Rigid End If If the hazard type on the current row in the redirection trajectory database is equal to BarrierType then it will be included in the analysis C 135 If barrier type in database BarrierType Then trajR_tot trajR_tot 1 cumulative count of trajectories End If MyrowR MyrowR I next redirection trajectory Loop Read redirection path coordinates from RSAPv3 worksheet MyrowR 4 first row with path data Do Until there are no more rows of data If hazard general type BridgeRails _ Or hazard general type Guardrails_Rigid _ Or hazard general type MedianBarriers_Rigid Then BarrierType Rigid Else Barrie

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