here - TxDOT Pavement Design Training
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1. 2 Click anywhere in the video box and a set of drop down menus will appear 3 Asa short cut hit the X key on the keyboard and the images will scroll forward In this process the images and GPR data are synchronized Hit the X key again to stop the scrolling 4 Use the Z key to move backward The function of each of the drop down menus and options available within PAVECHECK will be discussed in the remainder of this report Note PAVECHECK requires substantial free memory to display video images 2 MB is recommended Computer systems with small amounts of RAM or with large numbers of resident programs may have problems In this case the system will give an error message and Shut down 12 CHAPTER 4 USER S GUIDE FOR PAVECHECK USING SUPPLIED DATA The PAVECHECK set up disk automatically loads a complete data set from the Texas Transportation Institute TTI s Riverside campus into the ANNEX folder For this data set the project file annex prj has already been created and contains the files shown in Table 2 This data set contains FWD data and photographs of the test section The worked examples discussed in the reminder of this report will use these data to demonstrate the various features of PAVECHECK Table 2 Project Information for the Annex Sample Data Project file name prj is prj is the default extension name default extension name Project comment Annex test site about Must Encina MUA less than 120 charact2. T MRADAR Collecting GPR and Video Data Technical Memorandum to TxDOT July 2007 39
3. u Y gt 0 0 u Q Q gt 0 Q x O L L O LL gt lt q O PAVECHECK permits the user to e Display Ground Penetrating Radar GPR and synchronized video images The video shows the existing surface condition and the GPR identifies the subsurface condition which permits the user to potentially identify the possible cause of surface distress e Integrate other photographs of pavement cores or other relevant data which can be useful in the pavement evaluation e Integrate deflection data collected independently with Falling Weight Deflectometers e PAVECHECK also includes the MODULUS 6 backcalculation algorithms Scullion Chen and Lau 1995 The PAVECHECK system uses the layer thickness determined from the GPR data within the backcalculation analysis Figure 2 shows one example of a display from PAVECHECK 0 1026 0 1105 0 1184 0 1263 60 70 so Figure 2 Example of a Detailed PAVECHECK Display In Figure 2 the upper left quadrant shows a video mage of the location where data were collected The upper r ght shows a segment of color coded GPR data The basics of the GPR s gnal processing and the color coding system are given elsewhere Liu and Scullion 2001 In the GPR display the depth in inches is given on the vertical axis at the right of the display and the distance in miles and feet is given in the horizontal x axis The vertical red line to the left of the figure is where the displayed vi
4. 0 545 0 613 0 681 8 9 10 11 12 13 14 15 16 17 18 19 20 Ready mmf Figure 8 Combined FWD and GPR Display Re click the button and the FWD data will be removed The functions available in each of the display boxes will now be described in detail DESCRIPTION OF THE GPR COLOR DISPLAY Details of the GPR display screen are described below in Figure 9 e The top of the color display shows the location of each data item o Red marks indicate that a photo was taken at this location Click on the red mark and the photo will be displayed o Black marks indicate the location where a digital image was taken o Blue marks are where the FWD drop was made 15 PAD oboooo Red indicates a photo location High Limit Color Scale Slide Top black mark shows image location blue marks shows location of FWD data I I 0 266 0 355 0 444 Current Single Trace Location Top layer Dielectric Curve DMI mile feet i 1 0 33 0 177 Low Limit Color Scale Slide Color Scale Depth Scale inches Dielectric Curve Scale Figure 9 GPR Color Display The plot at the bottom of the display shows the dielectric value of first layer which is useful in checking the uniformity of surface layer density Periodic decreases signify compaction problems The scale at the left of this plot shows the numeric values of dielectric The numbers at the bottom of the plot are from the distance measuring instrument DMI
5. 9995 12 11 6 85 4 21 3 09 2 33 1 81 1 953 600 0 12 15 3 30 6 20 9 2 78 300 0 755 000 9947 14 40 7 81 4 41 3 2 25 41 71 1 44 600 0 86 1 33 1 21 2 2 77 300 0 802 000 10031 10 81 6 13 3 74 2 85 2 14 1 63 1 31 600 0 129 4 50 0 23 4 2 92 300 0 a upper part of file showing a summary of the results for all bowls 2 Station 0 009 mile 47 feet FWD No amp DMI 2 0mile 47 ft Temperature pav 38 F Test time 13 29 Thickness Mode Use top two layers Trace No amp DMI 48 0 mile 47 ft Cair O F Traceselect Close Fwb Error sensor Se er Image No amp DMI 5 0mile 50 ft suf 65 F Load 1b 10352 Dpth to Bedrock 300 0 inches MODULI RANGE ps1 R1 R2 R3 R4 R5 RO R Thin Thetrace Min Max Poisson Modulicksi Meas Defl mils 13 65 7 78 3 03 3 91 2 98 2 29 1 89 AC 2 3 2 3 600 0 600 0 0 35 600 0 Cale Defl mils 13 65 7 69 teak 3 89 2 91 2 24 1 75 BS 12 9 12 9 10 0 200 0 0 35 98 2 Percent Err 0 00 1 16 4 36 0 31 2 39 2 18 6 88 SB 8 0 0 0 10 0 50 0 0 35 50 0 S Moduli iksi 30 97 23 86 20 54 20 21 21 04 21 25 SG 276 9 0 0 13 0 15 0 0 40 16 6 b lower part of file showing details for each bowl analyzed Figure 27 Stored Results from the FWD Analysis 38 1 2 3 REFERENCES Scullion T Chen Y and Lau C L COLORMAP User s Manual with Case Studies TTI Report 1341 1 November 1995 Liu W and Scullion T User s Manual for MODULUS 6 0 for Windows TTI Report 0 1869 2 November 2001 Liu W and Scullion
6. Dialog BOX ooooonnccncncccnnonoccncnnnnnnnnnnnonnncnnnnnnononononcnnnnnnnos 30 Computing Thickness for Entire Annex Data Set ooooncnccccccnnononncnnnnnnnnnnononanononononononnnananos 36 Backcalculation Using a Single Set of Layer Thickness oooocccccncccnonnooccnncnnnnnnononanononoss 36 ResUlls OMA sa lese 37 Stored Results from the FWD Analysis u a een el an 38 Vill Table Sa es u re SZ me LIST OF TABLES Page Hardware Requirements for Running PAVECHECK 2220ccsnnssnsnesseeeeennnnnnnnnnnn 5 Project Information for the Annex Sample Data cccccccnnnonnnnnnnnnnnnnnnnnnonnnnnnnnnnnnnnnnanononss 13 Functions of Single Trace Analysis BU LODS ooocccccnccccnonononnnnnnnnnononononncnnnnnonononannnnnnnnnos 22 FUNCTIONS 201 VASO BOONS ns 26 EWD Control But a nen u ca 28 FWD Response Display Control Bullons sen a a a a a ea vccaet 29 Thickness Selec1 00 Ophon Tablesn see 31 CHAPTER 1 INTRODUCTION PAVECHECK is a software package used to integrate nondestructive test data from various testing systems to provide the pavement engineer with a comprehensive evaluation of both surface and subsurface conditions Figure shows the basic data that can be integrated Digital Video System FWD test 0 0 0 23 a 0 V GPR Test Take core Eu Compare with GPR result a Test location GPS system a map Figure 1 Elements of the PAVECHECK System Y gt Y
7. Station Range First Previous Next Last Fist Previous _Next_ lat Show the Deflection Bowl 14 a Run All Station Cancel C Use input thickness user input Trace select mode e Trace close to FWD Trace within A 6 ft MODULI RANGE ksi Result Layer type Minimum Maximum u Thickness fin Moduli ksi 10 0 10 20 30 40 50 60 70 80 340 1040 0 38 2 1 4 EnovSensor we 1 2 9 s sc Flexible Base 50 300 0 3 110 57 Tet 1083 577 sos s32 267 ats 191 exible Base v lo fo lo lo DB in AE Gravelly Soils v en 115 0 4 287 2 300 00 ttf tt S no PLOO 00 Back Calculation input data l Back Calculation Result Result Table Figure 23 FWD Backcalculation Analysis Dialog Box 30 SELECT STATION TOP LEFT The buttons on the top left are used to select the thickness modes There are s x options to select as explained in These options were added to provide the user flexibility in merging the GPR thickness information with the FWD bowl information In option 1 the user has already processed the GPR data for one station and saved those results Using option 1 this set of thickness data will be used to process all the deflection bowls To use options 2 3 or 4 the user must have already computed and saved thickness information for all the FWD test locations Using options 2 3 or 4 the layer thickness at each FWD test location will be varied in th
8. data are not displayed If the user wants to view the FWD deflection bowls or to analyze the FWD test data click the button on the toolbar Figure 19 For the annex prj data after clicking the button the FWD data identified in the project file will be displayed in the bottom left quadrant Click on this area with the left mouse button and Figure 20 will appear SS See E E Se I ps gt EI P Pres oe 222 959 920 300 254 20s 10 Oo 10 O a0 FH So sd O so Figure 20 FWD Frame with Buttons 21 Figure 20 shows the FWD deflection bowl at DMI 0 feet There are four lines that show the deflection bowls of four load levels used in the FWD test The thick blue line 1s the load level used for backcalculation This is the load level closest to 9000 Ib The raw data tables in the top right corner of the FWD frame are also for this load level Table 5 lists the functions of each of the buttons in the FWD frame Buttons Ml and EM are only active when there are FWD stations for which the backcalculation analysis has been completed Table 5 FWD Control Buttons l Show the FWD backcalculation dialog box to do the FWD backcalculation analysis The main computations are made here and will be discussed later 2 This button permits the user to display the raw FWD deflection data in graphical form Table 6 describes these options al Show the deflection data in tabular form u Show the FWD data for the previous
9. station Show the FWD data for the next station Show the previous FWD station that has already finished the backcalculation analysis 7 Show the next FWD station that has had the backcalculation analysis performed Print the FWD analysis result 28 Table 6 FWD Response Display Control Buttons Button Function fer Go back to the ma n FWD control buttons Display the center geophones deflection response for the entire project Bi Display the deflection graph for all seven sensors Display the center and outer geophones deflection response graph Display the outer geophones deflection response graph Display the load cell response graph for entire project a Display the air surface and pavement temperature graphs MODULUS BACKCALCULATION MODULE This module is the most complicated part in the PAVECHECK program The purpose of this chapter is to perform the FWD backcalculation with the thickness from the GPR trace analysis When the program reads the FWD data the deflection bowls from all of the load levels are read There is a separate dialog box allowing the user to select the load level and other FWD information before completing the FWD backcalculation To access this dialog box the user needs to click the HE button as shown in Figure 21 Once selected the dialog box shown in Figure 22 appears In this box the user can change the sensor locations the radius of loading plate and select the drop height to b
10. the right of the Zip Image file name row Click on the image file to be used i e us77nbol img and click Open 5 Add a project name and project comments or leave blank Figure 5 shows the completed input screen Read GPR data xj Velocity Factor oO Bounce factor 5s GFF test file name C Pavecheck us us nbol DAT Browse Metal Plate file name C Pavecheck us us mtpdat Browse ip Image file name c Pavecheck us us nbolIMG Browse PWD file name Browse GPS file name Browse Core file name Browse Project name Us ne Project Comment Tes of future Wilh site Cancel Figure 5 Completed Entries to Create a Project File for the US77 Data 6 Click the OK button The created US77NB prj file will be created and stored in the C PAVECHECK directory Note in the future to open up these GPR data and photos the Open Existing prj file icon a can be used 7 To display the GPR data and associated video images click on the Display the project icon The display shown in Figure 6 will appear 10 Untitled pDC File Tools Output Br RAS a 0 ml 39 ft 10 11 12 13 19 15 16 17 18 19 20 um Figure 6 Opening PAVECHECK Screen Showing US77 Data The upper box A contains the GPR color coded display for the section of US77 under testing The approximate depth scale in inches is at the right of the display and the color coding scheme used is at t
11. two test data sets One data set includes a folder called US77 which contains files of GPR and video images These data is the typical raw data collected in the field These files are used to demonstrate how data can be loaded and viewed within PAVECHECK A second data set named ANNEX 1s also loaded This complete data set includes FWD and photos of pavement cores This data set is used to demonstrate the full capabilities of PAVECHECK This system has tremendous potential to assist Texas Department of Transportation TxDOT engineers with future forensic and pavement rehabilitation studies The PAVECHECK framework can also assist in future pavement layer data base efforts and in documenting and evaluating the performance of research test sections 17 Key Words 18 Distribution Statement Ground Penetrating Radar GPR Falling Weight No restrictions This document is available to the Deflectometer FWD Pavements Backcalculation public through NTIS National Technical Information Service Springfield Virginia 22161 http www ntis gov 19 Security Classif of this report 20 Security Classif of this page 21 No of Pages 22 Price Unclassified Unclassified 50 Form DOT F 1700 7 8 72 Reproduction of completed page authorize PAVECHECK UPDATED USER S MANUAL by Wenting Liu P E Associate Research Engineer Texas Transportation Institute and Tom Scullion P E Research Engineer Texas Transportation Institute Report 5 4495 01
12. 4 Title and Subtitle 5 Report Date PAVECHECK UPDATED USER S MANUAL Wenting Liu and Tom Scullion Product 5 4495 01 P1 9 Performing Organization Name and Address 10 Work Unit No TRAIS Texas Transportation Institute APA The Texas A M University System 11 Contract or Grant No College Station Texas 77843 3135 12 Sponsoring Agency Name and Address 13 Type of Report and Period Covered Texas Department of Transportation Product Research and Technology Implementation Office September 2006 November 2007 P O Box 5080 14 Sponsoring Agency Code Austin Texas 78763 5080 15 Supplementary Notes Project performed in cooperation with the Texas Department of Transportation and the Federal Highway Administration Project Title Implementation of an Integrated Deflection and Ground Penetrating Radar Data Analysis System URL http tt1 tamu edu documents 5 4495 01 P1 pdf 16 Abstract 1 Report No 2 Government Accession No 3 Recipient s Catalog No FHWA TX 08 5 4495 01 P 1 The PAVECHECK data integration and analysis system was developed to merge Falling Weight Deflectometer FWD and Ground Penetrating Radar GPR data together with digital video images of surface conditions In project 4495 the earlier system has continued to be expanded with new capabilities This report provides an updated user s manual for the new program Itis accompanied by a CD that contains an executable program to load the software along with
13. P1 Project 5 4495 01 Project Title Implementation of an Integrated Deflection and Ground Penetrating Radar Data Analysis System Performed in cooperation with the Texas Department of Transportation and the Federal Highway Administration January 2008 TEXAS TRANSPORTATION INSTITUTE The Texas A amp M University System College Station Texas 77843 3135 DISCLAIMER The contents of th s report reflect the views of the authors who are responsible for the facts and the accuracy of the data presented herein The contents do not necessarily reflect the official views or policies of the Texas Department of Transportation or the Federal Highway Administration The United States Government and the State of Texas do not endorse products or manufacturers Trade or manufacturers names appear herein solely because they are considered essential to the object of this report This report does not constitute a standard specification or regulation The engineer in charge was Tom Scullion P E Texas 62683 ACKNOWLEDGMENTS This project was made possible by the Texas Department of Transportation and the Federal Highway Administration Elias Rmeili P E from the Brownwood District served as project director and his support for the implementation of PAVECHECK 1s greatly appreciated vi TABLE OF CONTENTS Page Eis RT Vill EIS 87 Lali 1X Chapter k MC nee l Chapter 2 Hardware Requirements for PAVECHECK ooooooocccnccnnncnonnnocnnnnnnnn
14. PR TRACE The most accurate estimates of layer thickness are obtained from the individual GPR reflections Processing these reflections within PAVECHECK will be described in this section Figure 13 shows the basics of GPR layer reflections The reflections from the surface and pavement interfaces are displayed as a plot of reflected energy volts against arrival time Radar Antenna Surface At First Second Interface Interface Retum Return A3 At At travel time in asphalt Atz travel time in base layer Figure 13 Principles of Ground Penetrating Radar The reflections of interest are the surface echo and the reflections that occur to the right of the surface echo By measuring the amplitude of these reflections and the time delay between them it is possible to compute both the layer dielectrics and layer thicknesses Complete details of the of this calculation process are given elsewhere Scullion Chen and Lau 1995 Click on the GPR trace box with the left mouse button and Figure 14 will appear This figure shows the drop down menus from processing the individual GPR traces 19 4 0 Armplitude o Dielestig Travel Time 2 ee eee A ee Oe ee A 41 0 1 077 Figure 14 Processing Options and Results Boxes in Single Trace Analysis As discussed earlier this pavement has a thin surface so it is recommended that the surface be removed by using the scissors option EM Once selected Fi
15. ate New Project File aaa 9 Completed Entries to Create a Project File for the US77 Data ne 10 Opening PAVECHECK Screen Showing US77 Data oooooooonnncncnnncnnnononoccnnnnnnnononananononos 11 Initial Display of Data in the Annex prj File occccccconoonnnnnnnnnnnnnononocnnnnnnnnnnnonananononss 14 Combined FWD and GPR Display sia ai 15 A A rr ARR ao etre ee 16 STEH ANESOL OPR Display une 17 Opuons in the GER Display asien DAR 18 GPR Display after Removal of Surface Reflection ooooooonncncnnnncnnnnononccnnnnnnnnnnnanononnos 18 Principles of Ground Penetrating Radar u a AAA A 19 Processing Options and Results Boxes in Single Trace Analys s nn 20 Using the Remove Surface Option in Single Trace AnalysSIS oooooonccnnnnccnnnnnnocnnnnnnnnnos 21 Results Prom S nsle Layer Analysis 2 Mocs aa a 21 Using the Automated Layer Thickness Tracking OPt10DS occcccccccnnnoonnncnnnnnnnonnnannnnnnnnnos 23 Typical PAVECHECK Video Image with Menu Options ooccccnccccnnnnoncncnnnnnnnnoninonnnnnnnnnos 25 Toolbar Button to Open or Close the FWD FraM ooocccnccncccnnnonocncnnnnnnononocnnnnnnnnnnnnnnnannnnss 27 EWD Frame with BUON a ii T Ween adsense 24 Toolbar Button to Access the FWD Information Dialog Box ceeeeneneennnn 29 FWD Device Information Input Dialog Box ooccccccccnoocncnnnnnnononnnonnnnnnnnnnnononanononnnnnnnos 30 FWD Backculation Analysis
16. deo image was taken The bottom left quadrant has the FWD bowls and the results from the backcalculation analysis For this deflection analysis the point specific layer thicknesses were used The quadrant at the bottom right has the GPR trace for the test location The computed layer thicknesses at this location are displayed these thicknesses that were used in the FWD analysis This User s Manual is intended to demonstrate how to load data into PAVECHECK and how to use the many functions available within the system The PAVECHECK software is provided on a CD that accompanies this report The PAVECHECK executable module will load the program and two folders containing test data into the default C PAVECHECK directory The US77 folder is intended to represent a typical new data set that will need to be input into PAVECHECK These data are used to demonstrate how to create a project file and view data The ANNEX folder contains an already existing comprehensive project file that includes FWD data CHAPTER 2 HARDWARE REQUIREMENTS FOR PAVECHECK Table 1 shows the minimum hardware requirements required for the system Table 1 Hardware Requirements for Running PAVECHECK Operation System Windows 98 Windows XP System Memory RAM At least 1 0 gigabyte 2 0 gigabytes or higher At least 1024x768 1280x1024 or higher Free Hard Drive Space At least 5 gigabytes 20 gigabytes System memory less than 1 0 gigabyte may result in frequent system cra
17. e backcalculation process Table 7 Thickness Selection Option Table Use Current GPR Trace Directly use the current single trace analysis thickness result for each FWD bowl However the subgrade thickness is obtained from the depth to bedrock calculation from the deflection data using the supplied AC layer thickness Use Thickness from GPR Directly use the thickness from the trace that is closest to or within 6 feet of the FWD loading plate Calculate bowl specific subgrade thickness 3 Only use the top AC layer Directly use the top layer s thickness from the trace thickness from GPR closest to or within 6 feet of the FWD loading plate This option is very useful if the base thickness 1s difficult to find from the GPR data Other layer thicknesses are input by the user The subgrade thickness is calculated by depth to bedrock calculation from the deflection data and AC layer s thickness thickness from GPR thickness from GPR 5 Use average thicknesses from the Average thickness from all traces analysis If the GPR GPR section is not very long and the interfaces between layers are clear this is a simple way to get the thickness User input thickness User can input all the thickness just like the current Modulus version 6 0 program The thickness is no longer related to the GPR trace thickness 31 MODULI RANGES In addition to the thickness input discussed above there are other data items required for the backcalcula
18. e trace being displayed For the subsurface reflections identify the maximum and minimum values The results from this analysis are shown in Figure 24 For the trace used in this example trace 206 the surface thickness was 2 5 inches and the base thickness was 12 3 inches e Use the HQ and OH buttons to apply the analysis set up used for the single GPR trace to the rest of the data set Black lines will appear on the traced layer interfaces Use the blue scroll bar to ensure that the layer interfaces have been correctly followed by the search algorithm Once this process 1s complete Figure 24 will be displayed on the computer screen 35 N H 1 1 1 0 68 0 136 0 204 0 272 0 341 0 409 0 477 0 00 a 1 1 1 gt E reer gt T am o 10 o 10 20 30 40 50 60 70 s0 Figure 24 Computing Thickness for Entire Annex Data Set STEP 2 COMPUTING LAYER MODULI USING ONE SET OF THICKNESSES e Click on the FWD quadrant enter the backcalculation module using the button e Click on the backcalculation button and then the first button and Figure 25 will appear Thickness Mode f Curent Trace from single trace frame Thickness from GPR Only use AC layer thekness from GPR Use top two lavers thekness fram GPR Station ft 200 000000 Section FF Station Range Previous Next Last from t o o reos Use average thickness from GPR f Use input thickness user input Trace s
19. e is set at this position The pavement section has a thin HMA layer nominally 2 inches thick and a thick granular base nominally 12 inches thick The thickness scale on the left is for estimation purposes only better thickness estimates for each layer will be described later Surface reflection Bottom of top layer Thickness scale inches Bottom of the base ro FJ hi Ed a Ed th I 13 0 1114 Figure 10 Significance of GPR Display 17 The upper left of corner of Figure 7 has the display shown in Figure 11 This display has several features that are useful Clicking the upper box will put the surface of the pavement solid red line at the very top of the display box The lower box with the scissors performs the surface removal technique This feature is very useful especially with thin surfaces After selecting this option Figure 12 is displayed The H option displays the header information for this file Figure 11 Options in the GPR Display Bottom of HMA Bottom base l B 1003 0 1114 o dar Figure 12 GPR Display after Removal of Surface Reflection The surface removal technique is highly recommended whenever thin surfaces are encountered which is very frequent in Texas As shown in Figure 12 once it is selected the surface of the pavement is now set at the top of the plot and the reflection from the top of the base is more clearly visible in the display 18 PROCESSING A SINGLE G
20. e processed When the FWD data are loaded the program automatically selects a drop height closest to 9000 Ib If all the drop heights are the same the last drop 1s selected Sensor location and radius are input from the FWD field file This box will only be changed 1f the user wishes to process data collected at a different load level or 1f the sensor locations are changed Under normal operations this box will not be changed Clicking the OK button will update the information and exit this dialog box ee lar Geo Po EA E De Figure 21 Toolbar Button to Access the FWD Information Dialog Box 29 FWD Information Rare 3 da ans ae i Distance to platelin jo fiz 24 3e jas sa 72 Selected Drop drop 2 10106 lb bi Radius of loading plate in 59 a era a A O Ze Figure 22 FWD Device Information Input Dialog Box The main FWD backcalculation 1s activated by clicking the EN button in Figure 20 the dialog box shown in Figure 23 will appear Most of the left side of this dialog box is for the input data and the right side is for the display of the result How to select thickness Select or display station Control Button Select Station e Current Trace from single trace frame Thickness from GPR C Only use AC layer thckness from GPR from t o Use top two layers thckness from GPR cc 1205 C Use average thickness from GPR Station ft 501 Of0000 Back Calculation Section
21. e the image frame to the next one 2 Play the image forward from the current location Clicking the mouse button in the image frame will stop the video e Move the image frame to the last one in the project 7 Show the GPR and FWD data at the current image frame location This action synchronizes all the other data to the image frame location E JN Display the information about this image frame Clicking this button and holding t down makes the image resize itself to 1ts original resolution Releasing the button will bring the image frame to its normal size red line will advance on the color display showing the location of the image in the GPR data Note the X key performs the same function Automatically play data forward The images will advance and the vertical red line will advance on the color display showing the location of the image in the GPR data Note the Z key performs the same function 26 The following is a very frequently used option when reviewing GPR data w thin PAVECHECK e Select a location of interest in the GPR color display using the left mouse button e Activate the video menu by clicking on the video display box with the left mouse button e Use the X key to scroll forward in the video Press the X key again to stop the video Press X one more time and the video will continue e To reverse use the Z key PROCESSING FWD DATA IN PAVECHECK When the PAVECHECK program starts the FWD
22. elect mode f Trace close to PAD Trace within A 6 ft MODUL RANGE ksi Layer type Minimum Maimun u Thickness in 340 1040 0 38 25 Flexible Base 50 300 0 3 12 35 Flexible Baze o o o o Gravelly Sails probable 15 0 4 285 1 value kzi Result nal 40 O0 1 20 30 4 50 60 70 80 eit ae we 1 2 a EN os e ot a ce jejejejeje E ERE ma 3313 50 22 60 112 20 82 22 08 DE iri 13 50 300 00 Figure 25 Backcalculation Using a Single Set of Layer Thickness 36 STEP 3 COMPLETE ANALYSIS USING DIFFERENT THICKNESS FOR EACH FWD LOCATION In this step the user enters other information such as the presence of a lime stabilized subgrade The modulus of the surface layer is also fixed at 600 ksi as this is a thin surface e Inthe Thickness Mode area select the option Use top two layer s thickness from GPR e Inthe Moduli Range area set the following o max and min moduli for surface 600 ksi o Poisson s Ratio for surface 0 35 o flexible base moduli range 10 to 200 ksi and o lime stabilized subgrade 8 inches thick e Select Run All Station and the First button and Figure 26 will appear Thickness Mode Current Trace fram single trace frame Thickness from GPR Only use AC layer thekness from GPR f Use top two layers thckness from GPR station ft f 805 00000 Back Calculation First Previous Next Last Sectio
23. ers 1800 ft long se 1 Subfolder if left blank it means these test data are Image folder kept in the project folder Die O GPS folder Core folder Core information kept in subfolder core Radar file Annex_GPR dat GPR file name Metal file Metal plate GPR file Image file ZIP mg Zipped video file FWD file Annex FWD FWD field test file with Dynatest R80 format wm o S To run PAVECHECK click on the icon Meee The menu bar shown previously in Figure 3 appears This time click on the Open Existing prj file la and navigate to the ANNEX folder in the PAVECHECK directory To select the data set click on Annex prj then to display the data click the button Figure 7 will appear 13 Ple Took Output es Pe A e M Figure 7 Initial Display of Data in the Annex prj File Click the button on the main toolbar This button will load the FWD data specified in the project file into the bottom left box Click on the FWD screen lower left quadrant with the left mouse button and Figure 8 will appear showing the pull down menu items for FWD analysis During FWD data collection four drops at different heights were made at each test location The four different colored lines are the deflection bowls for the first test location Details of this screen will be described later 14 File Tools Output Bram ALAS SS M Omi Oft 1 1 1 1 1 1 1 1 1 r O 68 0 136 0 204 0 272 0 341 0 409 0 477
24. gure 15 is displayed the displayed blue line is the true reflection from the lower pavement layers Once the remove surface is activated the software automatically measures the amplitude of the surface reflection and it uses this to compute the surface dielectric The symbols are automatically placed on the maximum and minimum points of the surface echo and the measured amplitudes and dielectric are displayed in the results box 20 4 0 Amplitude o 2 0 2 a Figure 15 Using the Remove Surface Option in Single Trace Analysis To compute dielectrics and thicknesses for the lower layers the user must first identify the reflections and use the mouse to place marks on the max and min values With the surface removal option activated the user must identify these peaks on the blue trace Peak identification 1s done by clicking on the maximum value then by convention the trailing negative peak Figure 16 shows the results of this operation are shown in Figure 16 below The results box 1s automatically updated For this particular example for trace 103 the computed thicknesses were 2 5 inches for the surface and 11 9 inches for the base In PAVECHECK a maximum of three layer thickness can be calculated o o o IC CA IC E OoOo OO OA 2 0 i a Figure 16 Results from Single Layer Analysis 21 Table 3 provides the function of each of the options in this screen Table 3 Funct
25. he far right both can be adjusted as will be described later The surface of the pavement is the solid red line just below Box A The lines below the surface come from reflections from lower layers in the pavement structure In this example there is a clear change in structure at 200 feet The vertical blue lines are user input markers which were entered during data collection to identify features along the section The operator maintains a log of these marks The black tick marks at the top of this box indicate locations where a video image was taken 11 Box B 1s the video image collected at 0 miles and 39 feet into the section If the operator clicks left mouse button on any location in Box A the corresponding video image will be displayed in Box B Box C is the GPR trace collected at one location initially set to the first location in the run If the operator clicks left mouse button on any location in Box A the corresponding GPR trace will be displayed in Box C The horizontal blue bar in the middle of the figure is a scroll bar it can be moved with the mouse It allows the user to move rapidly through the available data This feature is useful when long sections of highway have been tested Use the following steps to quickly review the data stored in this data set 1 Click anywhere in the color coded GPR data A vertical red line will appear and the video image and GPR trace from that location will be displayed
26. in the GPR van they give the distance in miles and feet The current DMI systems are calibrated at TTI s Riverside campus to be accurate to within 1 foot in 1 mile This calibration process is part of the MRADAR data acquisition program The calibration factors are stored within MRADAR Click anywhere in the color display with the left mouse button and a red vertical line will appear The video image FWD drop and GPR trace from that location will also be displayed in the other boxes of Figure 8 The color scale on the far right of the color display can be changed Place the mouse on either the red or blue arrow hold the mouse button down then move the arrow to a new 16 location To redraw the display with the new settings click the R button on the main menu bar The buttons govern the creation of the color display from the raw signal This process is useful for highlighting small reflections from lower layers e The depth scale to the right of the color display can also be adjusted Click on it with the left mouse button hold the mouse down and drag it to a new location Figure 10 shows the significance of the pavement data To generate this plot both the color display bars and thickness scale bars have been adjusted This adjustment is achieved by using the left mouse button and dragging the feature to the new location The surface of the pavement is the center of the strong red reflection The zero 0 inch position of the depth scal
27. ions of Single Trace Analysis Buttons This button will subtract the surface reflection based on the metal plate trace This technique is very effective if thin asphalt layers exist This button will automatically perform the single trace analysis This function 1s not available on this version but it will be added later Move to the previous trace Mil Move to the next trace The Undo button will allow the trace analysis go back to the beginning and restart the calculations This button will save the analysis results to the memory If the user does not click this button the results are discarded The HAJ OH buttons also save the result before further action Automatically track peaks in the backward direction and perform the layer thickness calculations Automatically track peaks in the forward location and perform the layer thickness calculations Goes backward to the trace that has the FWD test data This button helps users to locate the GPR trace at which the FWD field test data were Move forward to the trace that has already finished the single trace analysis Print out the single trace analysis results in detail 22 AUTOMATIC PEAKS TRACKING This option lets the user compute the thickness for a defined section Figure 17 shows the completed analysis To define the start and end of the section the curser is moved to the desired location in the color display and the Shift button and left mouse button a
28. n Run All Station E E E Station Range 16 15 14 13 12 11 10 Cancel from to 1805 7 Use average thickness from GPR Use input thickness user input Trace select made f Trace cloze to Pw Trace within A 6 ft MODULI RANGE ksi Layer type Minimum Masimum u Thickness in Moduli ksi eno eno 0 35 2 41 600 00 un mor Sensor Flexible Base 10 200 0 35 12 18 123 30 5 49 Lime Treated Subgra y 10 50 pa Je 50 00 DB fin Gravelly Soils probable E 0 4 277 4 1830 300 00 value kzi Figure 26 Results from Station 1 e Click OK and go to the output pull down menu in the main menu Figure 3 Select the save FWD data to ASCII file option then provide a name e Exit PAVECHECK and open the stored ASCII file in Wordpad Figure 27 will be displayed 31 File Edit Format wiew Help 3asic Information Project folder name C Pavecheck annex Project name Annex prj FwD test file name Annex FwD GPR test file name Annex_GPR dat 1801 total traces Metal plate file Mtp dat Iamge list file ZIP img 112 total images GPS file name GPS lst 0 total GPS reading Core image file Core Ist wD Test File Information FwD full path name c Pavecheck Annex Annex FWD Roadway ID Ride RUt Test Pad TTI Test date 7030123 Plate Radius 75 9 Cinches FwD Operater Roy Pilgrim Select Load Level 2 10106 1b No of drop
29. nd Shift right Mouse button are used The single trace analysis is then performed as described earlier In the case shown the surface removal option is used in both the color and single layer analyses The automated tracking function is activated using the backward HQ and forward OH buttons and Figure 17 will be seen Moving the curser anywhere within this window will now display the thickness for each location Right section limit Left section i limit Tracking pavement surface Tracking bottom of HMAC Tracking bottom of base I I I I I I I I r 0 0 111 0 223 0 334 0 446 0 557 0 669 0 780 0 392 0 1003 0 1114 Figure 17 Using the Automated Layer Thickness Tracking Options 23 Automated peak tracking does not work n all cases For this process to work the layer interfaces must be clear which is not always the case Some of the factors that can influence the success of the peak tracking function are listed below The age of the pavement Newly constructed pavements are eas er to track In many old pavements the reflections from the top of the subgrade are not clear Multiple overlays will create many sub interfaces which make tracking much more difficult Pavement deterioration like cracks will influence the quality of the captured GPR traces Moist conditions will change the dielectric values Localized moisture makes the peak tracking difficult Thin layers will make the two adjacent peak
30. ononononnnncnnnnononanananonss 5 Chapter 3 Loading PAVECHECK and Creating a Project Flle ooccccccccononnccnnnnnnnnnnnnnnnnnnnss 7 GPR DA Cole CO iy ee esse 7 Eoadinethe SO Water il een 7 Frau ro Reese ee ee rasen en een 8 Chapter 4 User s Guide for PAVECHECK Using Supplied Data eeennnn 13 Description ot the GER Color Display sea 15 Processa SmS GER Trad ae 19 Automatic Peaks Trackin oii accion weet ae 23 Usine the Digital Video Module une aus gare tanbidadaeiaeectien 25 Processing PWD Datain PAVECHECK serien a ae a a 21 MODULUS Backealeulat 01 Modules 2 29 Select SLALOM TOP Leti a nen an aM se ee 31 MODULT IR Ani nenne 32 Control Buttons Running Backcalculati0N ococccccconooooncnnnnnnonononononnnnnnnnnnnnnonanananoos 32 Chapeter 5 Backcalulation Case Study Using the ANNEX PRJ Daita 35 Step 1 Load Data and Compute Layer Thicknesses for Entire Data Set 35 Step 2 Computing Layer Moduli Using One Set of Thicknesses enen 36 Step 3 Complete Analysis Using Different Thickness for Each FWD Location 37 Referent ee ee 39 Vil Figure a ee O N N N NNN N KN BH Ra Ra Ra PF pa pa pa e pa So E de Se Yee SYS OS oO eS SON Se D LIST OF FIGURES Page Elements or ihe PAVE CHECK Syst ana l Example of a Detailed PAVECHECK Displays 2 Man Menu Screen MPAYEFCHECER ann 8 Input Screem to Cre
31. rocessed The resulting moduli values are in the results table together with the average error per sensor The solid line on the graph is the computed deflection bowl for the calculated moduli values 32 When running all station the program will depending on the station select box selection automatically change the layer thicknesses for each bowl But f the user checks the Section Range check box and inputs a valid DMI range the Run All button only calculates the stations within this DMI limit Without checking the Section Range all the stations will be analyzed 33 CHAPTER 5 BACKCALCULATION CASE STUDY USING THE ANNEX PRJ DATA This example will demonstrate most of the features available within PAVECHECK It will combine all of the steps described earlier to perform the computation of layer thickness and its use in backcalculation of layer moduli values STEP 1 LOAD DATA AND COMPUTE LAYER THICKNESSES FOR ENTIRE DATA SET e Open up the annex prj data set Open the FWD data using the button e Click on one location in the color GPR display a vertical red line will appear showing the location where the initial thickness are to be computed The video image and raw GPR data trace for that location will also be displayed e Inthe GPR trace display lower right click on the remove surface option using the EM button e Use the single layer analysis technique discussed earlier to compute the thickness for th
32. s 4 drops No of Stations 37 stations No of sensors T Sensor Locationlin R1 R2 R3 R4 R5 R6 R7 0 00 12 00 24 00 36 00 48 00 60 00 72 00 Load Measured Deflection mils Calculated Moduli values ksi Absolute Dpth to station lbs R1 R2 R3 R4 R5 RG R7 SURF CE1 BASECE2 SUBBCE3 SUBGCE4 ERR Sens Bedrock 0 000 10106 14 18 8 22 5 54 4 26 3 28 2 54 2 04 600 0 200 0 10 0 18 3 12 85 300 0 47 000 10352 13 65 7 78 5 05 91 2 98 2 29 1 89 600 0 98 2 50 0 16 6 1 74 300 0 100 000 9943 12 78 rane 4 88 3 78 2 82 2 13 1 76 600 0 103 8 50 0 16 8 1 34 300 0 153 000 10074 14 50 8 02 5 28 4 09 Sul 2 41 1 98 600 0 91 6 50 0 15 8 3 23 300 0 200 000 10019 11 78 6 64 4 24 3 44 2 76 2 24 1 76 600 0 123 3 50 0 18 3 5 49 300 0 253 000 10090 11 83 6 38 4 30 ad 2 65 2 02 1 68 600 0 119 8 50 0 19 0 4 64 300 0 300 000 10102 11 68 6 55 4 28 3 43 2 68 2 09 Lots 600 0 125 6 50 0 18 9 4 41 300 0 353 000 9713 16 64 10 02 5 69 4 13 3 06 2 35 1 95 600 0 70 9 20 8 a E 3 27 300 0 401 000 10011 14 28 5 7 3 31 2 73 2 21 1 79 1 56 600 0 67 5 50 0 23 3 str 300 0 454 000 10194 9 86 4 68 2 91 2 52 2 08 1 07 1 41 600 0 137 0 50 0 28 0 10 72 300 0 501 000 10047 10 83 SSTT 4 03 3 32 2 67 2 19 1 91 600 0 166 1 50 0 19 6 8 59 300 0 554 000 10090 9 73 5 49 3 64 2 90 2 29 1 80 1 50 600 0 200 0 12 1 26 1 10 86 300 0 601 000 10082 12 50 7 26 3 94 2 51 2 23 1 79 1 31 600 0 92 4 36 6 22 1 4 82 300 0 654 000 9939 10 10 343 3 76 2 98 2 29 1 78 1 46 600 0 200 0 ze 23 2 10 10 300 0 702 000
33. s overlap Defects or localized variation in the pavement structure will challenge the peak tracking Buried pipelines or metal objects will change the waveform of the GPR traces Sections of the GPR survey containing a bridge or sections that are close to a bridge will confuse the peak tracking 24 USING THE DIGITAL VIDEO MODULE The integrated video is a key module within PAVECHECK The user can move back and forward throughout the pavement section and look at surface distresses and subsurface GPR data This feature is very important when the data are being used to diagnose the cause of the distress and to identify locations where coring is required Figure 18 shows the basic video display The distance information in miles and feet is shown in the lower left of the image The options available for viewing the data are shown at the top of the figure i Mindo E i en MEER u Figure 18 Typical PAVECHECK Video Image with Menu Options Table 4 describes the various menu options Note the video image displayed is automatically synchronized with the other PAVECHECK screens color coded GPR and the single GPR display trace 25 Table 4 Functions of Video Buttons No Button Function Show the first image of the project 2 Play the images backward from the current location Clicking the mouse button in the image frame will stop the video hal noi Move the image frame to the previous one mi Mov
34. shes The system has also been reported to run well on the new Microsoft Vista operating system but this operating system has not been fully evaluated CHAPTER 3 LOADING PAVECHECK AND CREATING A PROJECT FILE In this section the steps required to load the system and create a project or work file will be explained For this example the data sets provided in the US77 folder will be input into PAVECHECK GPR DATA COLLECTION GPR and synchronized video images are collected using the MRADAR data acquisition system details of which are given elsewhere Liu and Scullion 2007 The minimum data required for the system are three files as provided in the US77 folder e the GPR data collected over the test section US77nbol dat e the metal plate GPR file collected after data collection US77mtp dat and e the zipped image file provided by the GPR data collection operator US77nbol img LOADING THE SOFTWARE PAVECHECK is provided on a CD that contains a PAVECHECK_ setup exe file To install fur PAVECHECK double click the PAVECHECK_Setup icon and follow the instructions After hitting the Start button if the program asks for permission to overwrite existing DDL files click NO The two work folders US77 and ANNEX will automatically be loaded into the C PAVECHECK directory The US77 directory contains the three data files described above After installation the PAVECHECK icon will be loaded onto the compu
35. ter desktop CREATING A PROJECT FILE Click on the PAVECHECK icon on the desktop and the main menu screen shown in Figure 3 will appear Untitled pDC File Tools Output Gr G oo E e tb de n El So M Show or Hide the Deflection Response frame Open Existing pry file Figure 3 Main Menu Screen in PAVECHECK The function of each of the menus in Figure 3 will be described later in this report The following steps will create a project file prj This example demonstrates the minimum data input requirement for PAVECHECK a 1 Click on the Open New Project icon es and the following box will appear Figure 4 Read GPR data gt Velocity Factor jo Bounce factor ss GPR test file name Browse Metal Plate file name Browse zip Image file name Browse FD file name Browse GPS file name Browse Core file name Browse Project name Project Comment Eea Figure 4 Input Screen to Create a New Project File 2 Click on the Browse button to the right of the GPR test file name row Navigate to the location of the US77 folder supplied with the system Click on the GPR data file to be used 1 e us77nbol dat and click the Open button 3 Click on the Browse button to the right of the Metal plate file name row Click on the GPR metal plate file to be used 1 e us77mtp dat and click the Open button 4 Click on the Browse button to
36. tion process These items are input in the lower left part of the backcalculation dialog box The analysis routine within PAVECHECK is essentially the system included in MODULUS 6 Therefore the process is limited to a maximum of a four layer analysis where the lower layer is a semi infinite stiff layer buried under a calculated subgrade thickness layer The user required inputs to run the backcalculation analysis are as follows e moduli range for each layer including minimum and maximum moduli values e Poisson s ratio for each layer e last layer or the subgrade layer need to input the most probable moduli value and e add any additional layers such as subbases For the lower layers the user can select the material type to define the input values using the drop down list The material types provide a first cut set of moduli values that can be overwritten by the user CONTROL BUTTONS RUNNING BACKCALCULATION There are two ways to run the FWD backcalculation one is a single bowl FWD backcalculation with the first button Back Calculation another is running all stations with the button Run All Station In the single bowl backcalculation the user can process one bowl at a time by using the First Next Previous or Last buttons If the thickness data are available and the user selects options 2 3 or 4 in the station select box the layer thicknesses will be varied for each bowl being p
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