Home

TRAP - Bridge Engineering Software & Technology (BEST) Center

1. ee OUTPUT SYSTEM MOD OF ELAS WIND INTS CABLE OPTION OPTION KSI KSF OPTION 3 4 29000 00 07500 0 GENERAL TRUSS CONFIGURATION SPAN LENGTHS SPAN 1 FEET 189 72 CONFIGURATION DETAILS DISTFACT OPTION DISTANCE DEAD LOAD CURB DIST BETWEEN DETAIL DISTANCE FACT TRUSSES FACTOR FT FT 23 00 000 26 250 1 200 7 8 TRUSS RATING AND ANALYSIS PROGRAM TRAP PAGE Z GROUP LOADING ANALYSIS TABLE 1 2 GENERAL LIVE LOAD AND RATING DATA ee See M A INVENTORY RATING DATA OPERATING RATING DATA INTERSTATE AASHTO ALLOWABLE AASHTO ALLOWABLE MILITARY LOAD STRESS LOAD STRESS LOADING NAME FACTOR NAME FACTOR 1 Y 0 N MEMBER CABLE MEMBER CABLE HS 15 55 00 HS 15 75 00 0 STATE VEHICULAR LOADINGS VEHICLE l VEHICLE 4 VEHICLE 3 ALLOW STRESS NAME NAME NAME FACTOR MEMBER CABLE 00 00 TRUSS RATING AND ANALYSIS PROGRAM TRAP PAGE 47 GROUP LOADING ANALYSIS TABLE 17 3 GROUP LOADING III MEMBER FORCE IN LOWER CHORDS MEMBER LCT W W L L F GROUP III GP I 0 3W WL LF 1 25 MAX MIN KIPS KIPS KIPS KIPS KIPS L 15 20 92 1 77 2 54 184 42 120 34 213 20 92 1 77 2 54 184 42 120 34 L 3 L 4 31 43 2 59 3 72 270 87 176 68 L 4 L 5 37 17 3 00 4 31 314 72 205 18 L 5 L6 39 77 3 18 4 47 333 36 219 19 L 6 L 7 37 17 3 00 4 31 314 72 205 18 L7L8 31 43 2 59 3 72 270 87 176 68 819 20 92 1 77 2 54 184 42 120
2. B Wind Load on Live Load a Use 100 Ib per linear foot 1 46 KN m and distribute it to the panel joints They are applied over the entire truss b The force from step a is 6 feet 1 83 m above deck Find moment by force 6 feet 1 83 m This moment produces the vertical force on the windward plane truss The vertical force moment truss width C Like step f of part A it can be decided whether the vertical forces exert on the lower or upper panel points 5 5 RATING The TRAP system has the capability to determine the structural rating for any general truss bridge The truss can also be prestressed including indeterminate truss bridge structures of up to six spans For rating truss bridge with counter members ignore the rating factors for compression of counter members The rating procedures used by the program follow the standard AASHTO specifications for Highway Bridge Structures Working stress analysis procedures are used in computing the induced axial stresses of all truss members LFD and LRFD use the WSD analysis results with factors multiplied The AASHTO Manual for Condition Evaluation of Bridges serves as the guide for rating bridges Three rating types are defined 1 2 3 INVENTORY RATING determines the bridge capacity under normal use and at the stress level for which the structure was originally designed Usually this allowable stress is 0 55 Fy OPERATING RATING determine
3. Decimal The net area of the member YIELD STRESS KSI or MPa Decimal The yield stress of the material used as given by the AASHTO specifications INFLUENCE LINE OPTION Integer An option which will allow the user to select which member influence line will be output 1 Input 0 or leave blank if no influence line output is desired 2 Input 1 if a table of influence line values for the given member is to be output EFFECTIVE LENGTH FACTOR Decimal The effective length factor of the member If left blank 1 is assumed TEMPERATURE CHANGE Decimal The temperature change of the member If left blank 0 is assumed NOTE 1 For a through or deck truss with first and last vertical members the first and last loaded members should be the first and last vertical members correspondingly while their deck locations can be specified accordingly 2 For a through truss without first and last vertical members the first and last loaded members should be the fist and last lower chords correspondingly while their deck locations should be specified as zero or left blank The other vertical members should be loaded sequentially from sequence no 2 3 For a deck truss without first and last vertical members the first and last loaded members should be the first and last upper chords correspondingly while their deck locations should be specified as zero or left blank The other vertical members should be loaded sequentially from sequence no
4. 00 00 18 82 18 82 L3U3T 45 22 27 14 HS 28 26 HS 18 07 Hs 73 47 HS L3U3 B 78 53 10 50 HS 234 03 L 58 02 H5 112 55 L L4U4T 12 57 32 24 HS 24 64 HS 19 67 HS 37 21 HS 1414 45 88 20 17 HS 29 57 HS 25 71 HS 75 45 HS L5U5T 4 51 16 45 12 15 HS 20 96 HS 7 654 HS 1505 28 79 12 15 HS 35 29 H5 16 65 HS 64 09 HS L6Us6T 4 51 16 42 HS 12 13 HS 20 94 H5 7 62 HS 28 79 12 11 HS 35 29 HS 16 58 HS 64 08 HS L7 U7 T 12 57 32 24 HS 24 64 HS 19 67 HS 37 21 HS L7U7B 45 88 20 17 HS 29 57 HS 25 71 HS 75 45 HS 45 22 27 14 HS 28 26 HS 18 07 HS 73 47 L8USB 78 53 10 50 HS 34 03 L 68 02 HS 112 55 L L909T 35 47 46 81 HS 00 82 28 HS 35 47 L9USB 19 82 400 00 18 82 18 82 7 20 TRUSS RATING AND ANALYSIS PROGRAM TRAP PAGE 41 PRESTRESSED STEEL THUSS BRIDGE TABLE 10 54 FORCE SUMMARY FOR DIAGONAL MEMBERS AASHTO LOADING RESULTS TOTAL MAXIMUM MAXIMUM MAXIMUM MINIMUM DL TENSION COMPRESSION MEMBER FORCE MEMBER FORCE MEMBER T PL TYPE LIAI PIr DI LL I TYPE TYPE F K K K K L1U2 238 29 00 96 09 L 238 29 334 38 L U2L3 111 87 51 44 L 14 25 HS 163 31 L 97 62 HS U3L4 13 03 37 08 L 25 57 HS 50 11 L 12 54 HS UALS 37 68 37 01 HS 28 65 74 69 HS 9 03 HS 1 5 6 3 31 18 79 HS 14 51 HS 22 09 HS 11 21 HS U5L6 3 31 18 81 14 54 HS 22 12 HS 11 23 HS 1607 12 32 34 62 HS 28 84 HS 22 29 HS 41
5. X 4 gt gt X gt gt gt lt lt X lt gt lt gt gt Table A 1 Index of Output Tables OUTPUT LEVEL NO TABLE TITLE 1 2 3 15 0 ALLOWABLE FORCE 15 1 Allowable Force Summary for Lower Chord Members 15 2 Allowable Force Summary for Upper Chord Members 15 3 Allowable Force Summary for Additional Members 15 4 Allowable Force Summary for Vertical Members 15 5 Allowable Force Summary for Diagonal Members 16 0 TRUSS RATING SUMMARY DL LL D 16 1 DL LL I Rating Summary for Lower Chord Members 16 2 DL LL I Rating Summary for Upper Chord Members 163 DL LL I Rating Summary for Additional Members 164 DL LL I Rating Summary for Vertical Members 16 5 DL LL I Rating Summary for Diagonal Members 16 6A PL LL I Rating Summary for Straight Cables 16 6B PL LL I Rating Summary for One Drape Cables 16 6C PL LL I Rating Summary for Two Drape Cables 16 7 Summary of Inventory and Operating Rating ES ES ES 16 8 Summary of Posting Vehicle Rating These tables are generated for the Cable Option only A 10 Table A 1 Index of Output Tables OUTPUT LEVEL TABLE TITLE COMBINATION OF LOADS Group Loading IA for WSD LFD or Strength II for LRFD Group Loading II for WSD LFD or Strength III for LRFD Group Loading ITI for WSD LFD
6. 00 117 48 L 61 00 L3L4 236 59 86 26 L 00 322 85 L 236 59 1415 224 93 98 01 L 00 322 94 L 224 93 L5L6 244 51 101 59 L 00 346 11 L 244 51 L6L7 274 93 100 00 L 00 374 93 L 274 93 L7L8 136 50 83 90 L 00 220 49 L 136 59 819 161 00 58 94 L 00 219 94 L 161 00 L 9 161 00 58 94 L 00 219 94 L 161 00 TRUSS EATING AND ANALYSIS PROGRAM TRAP PAGE 39 PRESTRESSED STEEL TRUSS BRIDGE TABLE 10 2A PL DLU IIry FORCE SUMMARY FOR UPPER CHORD MEMBERS AASHTO LOADING RESULTS TOTAL MAXIMUM MAXIMUM MAXIMUM MINIMUM DL TENSION COMPRESSION MEMBER FORCE MEMBER FORCE MEMBER PL FPL DL LI I PL DL IL I K K K K K U2U3 241 92 00 88 21 L 241 92 330 12 L U3U4 277 70 00 101 01 L 277 70 378 71 L U4U5 296 63 00 107 70 L 296 69 404 39 L USU6 298 193 00 106 64 L 298 19 404 84 L U617 296 69 00 107 70 L 296 69 404 39 L U7U8 277 70 00 101 01 L 277 70 378 71 L UBUS 241 92 00 88 21 L 241 92 330 12 L 7 19 TRUSS RATING AND ANALYSIS PROGRAM TRAP PAGE 40 PRESTRESSED STEEL TRUSS BRIDGE TABLE 10 45 PIADIALIAI FORCE SUMMARY FOR VERTICAL MEMBERS AASHTO EOADING RESULTS TOTAL MAXIMUM MAXIMUM MAXIMUM MINIMUM DL TENSION COMPRESSION MEMBER FORCE MEMHER FORCE MEMBER ICT gt PL TYPE LL I TYPE PI DI LL I TYPE FL DL LI I K K K X L2U2T 35 47 46 81 HS 00 52 28 HS 35 47 L2U2B 18 82
7. 241 25L 26L 271 BL 29L 301 9500 5600 27 28 28 30 31 0 00 900 00 0 00 900 00 7 2625 38 12 1025 3 amp 7 2625 38 5 0325 38 5 0025 38 9825 38 4825 38 4225 38 6025 38 1525 38 6025 38 3 4225 38 3 4825 38 4 9825 48 5 0025 38 5 0325 38 7 2625 38 12 1025 38 7 2625 38 4 9825 38 3 4825 38 3 0425 38 3 0425 38 3 0425 38 1 9025 38 3 7025 38 4 4425 38 3 2525 38 2 2525 38 3 6225 38 6 1925 38 6 7425 38 6 7425 38 6 1925 3B 5 6225 38 3 6225 3B 3 4025 38 3 3625 38 3 4025 38 3 2525 358 3 2525 38 3 4025 38 3 3825 38 3 4025 38 3 6225 38 5 6225 38 6 1925 38 6 7425 38 6 7425 38 6 1925 38 3 6225 38 3 2525 38 3 2525 38 3 4425 38 3 7025 38 bh LJ L fa 53 940 78 130 53 940 52 130 47 630 45 380 41 440 39 440 30 940 30 940 30 940 38 440 41 440 45 380 47 630 52 130 53 940 79 1360 53 940 45 320 41 440 37 440 37 440 37 440 27 940 64 260 44 500 37 440 35 440 36 940 46 860 48 360 48 360 46 B60 45 360 36 540 41 440 44 000 41 440 35 440 35 440 41 440 44 000 41 440 36 940 45 360 46 860 48 360 48 360 46 860 36 940 35 440 37 440 44 500 64 260 53 940 79 1230 53 940 52 130 47 630 45 380 41 440 38 440 30 940 30 940 30 940 39 440 41 440 45 380 47 630 52 130 53 940 75 130 53 940 45 380 41 440 37 440 37 440 37 440 27 940 62 970 44 060 36 690 34 730 36 570 44 520 46 430 46 430 44 520 43 090 36 570 41 030 43 5
8. Optional program output consists of tables of influence line values of the truss for member forces and prestressed cables Output of TRAP Table 4 3 Reaction Influence Line Values requires that OUTPUT LEVEL 3 on Data Type 0103 Additionally output of any member force influence line values is obtained by setting INFLUENCE LINE OPTION 1 on data types 0501 0502 0503 and 0504 for prestressed cables This will cause output of TRAP Table 4 1 Member Influence Line Values and TRAP Table 4 1A Cable Influence Line Values for Prestressed Cables 5 0 METHODOLOGY This program has the capability of performing an analysis and rating of a truss bridge which can be prestressed with several cable layouts of a general geometry and member configuration The following are the assumptions upon which the program is based 5 1 STRUCTURAL ANALYSIS OF TRUSS The stiffness method see any text on matrix structural analysis is applied herein to the analysis of a plane truss The form of the method adopted assumes that the structure is linearly elastic all connections are pinned and all loads are considered to be acting at the panel points Basic output tables from the method are member axial forces reactions and joint deflections For a structure to be linearly elastic it is assumed that the material must obey Hooke s Law and that displacement must be small in comparison with overall dimensions 52 DEAD LOAD In order to yield maximum
9. or page orientation make the appropriate modifications 3 Click OK 1 5 To view the tables 1 Click the View Tables tab 2 Click on a table you would like to view from the list on the top 3 The selected table will be displayed on the bottom To print the tables 1 Click the Print Tables tab 2 Click on the tables you would like to print from the list on the bottom 3 The selected tables will appear on the top list 4 Click Print Note To delete a table from the top list click on the table Graphic Plot By clicking on the word Graphic shown in the menu bar of the Main Menu screen you will be transferred to the TRAP Graphic Utility screen The geometry of the truss will be shown on the screen The user may toggle joint and member numbers zoom or unzoom the graphics The graphic picture also can be printed out by clicking on the Print option 1 6 2 0 DESCRIPTION 21 GENERAL This chapter describes the application capabilities of the TRAP program A summary of these features along with the limitations is given in Table 2 1 Summary of Program Features and Limitations A more detailed description of the program and the equations used are given in Chapter 5 0 Methodology 2 2 STRUCTURAL MODEL The bridge structure is modeled as a two dimensional truss with loads applied in the plane of the truss The deformations member forces and reactions are solved utilizing the stiffness method in matrix format
10. 0401 0401 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0601 0601 0602 0602 0603 0603 0604 0604 0702 0702 2 1 0 0 2 21 08 3 42 16 4 63 24 5 84 32 6 105 40 7 126 48 8 147 56 9 168 64 10 189 72 IL 2L 2L 3L 3L 4L 41 5L 5L 6L 6L 7L 71 8L 8L 9 91 1 100 20 110 30 120 40 130 50 140 60 150 70 160 171 20 181 30 191 40 20L 50 211 60 221 70 23L 8U 24L 9U 25L 1U 26L 3U 27L 4U 28L 5U 29L SU 30L 60 31L 6U 32L 7U 33L 80 34L 10U l 8 1 53 1 15 1 1 0000000000 0000000000 1 000300 G S 10 DAKO 10 n gt 10 0 ANAN 0 WON AM b UI 29 75 1 23 27 5 30 5 31 5 31 5 30 5 27 5 23 000 0 21 08 42 16 63 24 84 32 105 40 126 48 147 56 168 64 469 469 721 829 685 829 721 469 469 3 277 3 1 2 97 2 97 2 97 3 1 3 277 1 54 2 48 1 54 1 54 1 54 1 54 2 48 1 54 2 97 1 96 1 54 1 54 1 54 1 54 1 54 1 54 1 96 2 97 23 0 27 5 30 5 31 5 31 5 30 5 27 5 23 0 12 12 12 12 12 12 12 12 12 15 15 is 15 15 15 15 12 12 12 12 12 12 12 12 15 15 15 15 15 15 15 15 15 1555 0 075 19 5 19 5 34 5 28 5 34 5 19 5 19 5 28 67 32 35 35 25 35 25 35 25 32 35 28 6
11. 1 L 1L 3 0 85 216 0 0503 003 1 L 7 L B U 3 0 85 216 0 7 16 23 0 30 36 30 36 30 36 27 5 36 24 37 36 8 75 36 13 26 35 8 75 36 6 75 36 8 75 36 B 75 36 13 26 36 36 36 36 coooOocoOooooo0mpooooooooeoocoaoooPpooooococomnu 36 4 h 4 4 4 4 v lt 4 gt q h H HU HU O O O O ps J ps ps J fd fd a fa 26 25 v P 4 1 2 0504 0504 0601 0601 0602 0602 0603 0603 0604 0604 0702 0702 53 L 4 0 0 0 0 189 72 189 72 189 72 189 72 2 3 5 2 3 6 0 85 2 3 7 2 3 216 0 B 2 3 9 50 0 2 3 7 17 OUTPUT RESULTS 7 18 TRUSS RATING AND ANALYSIS PROGRAM TRAP PAGE 38 FRESTRESSED STEEL TROSS BRIDGE TABLE 10 18 PLADIFLLHI FORCE SUMMARY FOR LOWER CHORD MEMBERS AASHTO LOADING RESULTS TOTAL MAXIMUM MAXIMUM MINIMUM DL TENSION COMPRESSION MEMBER FORCE MEMBER FORCE MEMBER t PL Lidl TYPE LLH PleDitiiel 0 K K K 1112 61 00 56 48 L 00 117 48 L 61 00 1213 61 00 56 48 L
12. 27 SdIX 1119135 J IXV 59 12 45 UNV 611914 43IXV ONIQVOT J3Ondl 244 14 o 9 12 45 IXY 91534 9NIQVOT SSHHLS MOTIV 0 z 122 BE 41 O ON 4O L2 V NOLOV4A 1 54 5544151 voi 5534151 0 01 SNIUVO ETEVMOTIV DLHSVY 318 VNOT1Y JlIVISUd4iNI DNTIVE ONAIVHAJdO JNILVH ANLNGANI NOILVNYOINI X NUL SH H uVOT1 3A11 OLHSVY LVN9 1530 I 3 21H3A HOLOV3 583HlS MOTI NOLLVNYOANT 9421504 SONIQVOT WV T02IH3A 1 15 E i a F a VLVO SNILVE UYOT 3A17 TV83N35 7 28 9 1514 Duy ls u 2 5 YNT DVS LON JI YNT 5 ONT A Of DY aS 43 LON 1 5413 119134 ANTAZO LON 1 2 37091H3A TIYIS J xv JT WUDSIBSA 7 29 RE U DE DE DN AES RM GAZA IE RS SINIOd U INVd SlMlIOd Yh V SINIOd TANVU lHi d T3NVd 7 30 UJIALLSAC ANOTA AQ ASMA 501114 2DUJHIUN JuV 91 yt any I NUHL OF SNWNTOD 501414 4 JUV 1 UNY 6 5880102 F P ATIVNLIV SI 111414 VNDISIA ANV NOILV2OT NJ mIW T ILON PT 50070 AA ogo cL d 6T 91 1 i J 21530 2 mic o B o S
13. 29 32 36 30 25 5 36 19 5 16 57 36 19 5 16 57 36 28 67 24 37 36 32 35 27 5 36 0103 3 2 29000 0 0104 0104 189 72 0301 0301HS 15 55 6 HS 15 75 9 0 0801 0401 1 0 0 0 0 I 0401 2 21 08 0 0 21 08 23 0 0401 3 42 16 0 0 42 16 27 5 0401 4 63 24 0 0 63 24 30 5 0401 5 84 32 0 0 84 32 31 5 0401 6 105 40 0 0 105 40 31 5 0401 7 126 48 0 0 126 48 30 5 0401 8 147 55 0 0 147 56 27 5 0401 9 168 64 0 0 168 64 23 0 0401 10 189 72 0 0 11 0501 0501 1L 1L 2 1 469 12 0501 2L 2L 3 469 12 0501 3L 3L 4 221 12 0501 41 4L 5 829 12 0501 SL 5L 6 685 12 0501 6 7 829 12 051 7L 7L 8 721 12 0501 81 8L 9 469 12 0501 9L 9L 10 10 469 12 0501 100 2U 3 3 277 15 0501 lity 3U 4 3 1 15 0501 22U 40 5 2 97 15 35 25 0501 13U SU 6 2 97 15 35 25 0501 140 7 2 97 15 35 25 0501 15U 70 3 1 15 32 35 0501 160 BU 9 3 277 15 28 67 0501 17L ZU 2 223 1 54 12 10 3 0501 18L 3U 3 3 27 5 2 48 12 15 6 0501 195 4U 4 4 30 5 1 54 12 30 3 0501 20L SU S 5 31 5 1 54 12 10 3 0501 21L 6U 6 6 31 5 1 54 12 10 3 0501 22L 7U 7 7 30 5 1 54 12 10 3 0501 23L 8 8 27 5 2 48 12 25 6 0501 241 90 9 823 1 54 12 10 3 0501 251 2U 2 2 97 15 35 25 0501 26L 30 2 1 96 15 14 7 0501 271 40 3 1 54 15 10 3 0501 28L 50 4 1 54 15 10 3 0501 29L SU 6 1 54 15 10 3 0501 301 5 1 54 15 10 3 0501 31 60 7 1 54 15 10 3 0501 32L 7U 8 1 54 15 10 3 0501 33L 8U 9 1 96 15 14 7 0501 34 100 9 2 97 15 35 25 0502 0502
14. 31U 32U 33U 34U 350 360 370 380 390 400 410 420 430 440 4517 460 470 48U 49U 50U 51U 52U 53V 54U 55U 560 57U 58U 59U 60U 62L 62L 63L 64L 65L 66L 7L 81 BL 101 11L 12L 13L 14L 15L 16L 17L 181 131 201 211 221 231 241 251 261 271 281 291 30L 10 20 40 7U BU 9U 10U 11U 12U 13U 14U 150 160 170 18U 19U 260 21U 220 23U 240 25U 26U 27U 28U 29U 30U 10 2U 3U 4U 50 60 Qi tn 11 0038 00141 060141 060 11 0038 00144 000144 000 11 1038 00126 980126 980 11 0038 00119 320119 320 11 0038 00100 890100 890 11 0038 00 83 630 83 630 10 9038 00 51 750 42 950 11 0038 00 51 750 51 750 11 0038 00 51 750 51 750 11 0038 00 51 750 51 750 11 0038 00 51 750 51 750 10 9038 00 51 750 42 950 11 0038 00 83 630 83 630 11 0038 00100 890100 890 11 0038 00119 320119 320 11 1038 00126 980126 980 11 0038 00144 000144 000 11 0038 00141 060141 069 11 0038 00144 000144 000 11 0038 00135 980135 980 11 1038 00127 890127 890 11 3038 00119 630119 630 11 0038 00105 390105 390 11 0038 00 66 750 65 420 10 7032 00 47 250 47 250 10 7032 00 54 750 54 200 11 0032 00 88 890 88 890 11 0032 00104 660104 660 11 0032 00112 740112 740 11 0032 00120 240120 240 11 0032 00120 240120 240 11 0032 00112 740112 740 11 0032 00100 890100 890 11 0032 00 85 130 85 130 11 0032 00 65 250 65 250 10 7032 00 47 250 46 300 10 7032 00 47 250 47 250 10 7032 00 47 250 42 530 10 7032 0
15. 34 L 9 110 20 92 1 77 2 54 184 42 120 34 TRUSS RATING AND ANALYSIS PROGRAM TRAP GROUP LOADING ANALYSIS TABLE 17 3 GROUP LOADING III PAGE 48 MEMBER LCT W W L L F GROUP III GP I 0 3W WL LF 1 25 MAX MIN KIPS KIPS KIPS KIPS KIPS 9253 32 14 2 64 3 80 180 66 276 97 U3UA 37 55 3 03 4 36 207 24 317 89 U4US5 40 41 3 23 4 65 221 35 339 51 U5U 6 40 97 3 27 4 60 223 19 340 80 2657 40 41 3 23 4 65 221 35 339 51 977598 37 55 3 03 4 36 207 24 317 89 987599 32 14 2 64 3 80 180 66 276 97 TRUSS RATING AND ANALYSIS PROGRAM TRAP GROUP LOADING ANALYSIS TABLE 17 3 GROUP LOADING III MEMBER LCT W W L L F GROUP 111 PAGE 49 GP I 0 3W WL LF 1 25 MAX MIN KIPS KIPS KIPS KIPS KIPS 1202 T 4 64 48 1 25 11 96 61 28 L2U2 B 4 64 48 1 25 17 55 12 55 L3U3 T 6 08 41 1 45 18 68 32 72 L3 U3 B 6 08 41 1 45 51 47 92 99 L4UA4 1 25 06 1 16 16 85 8 56 1404 B 1 25 06 1 16 19 29 61 63 1505 T 1 02 08 1 14 16 80 8 51 1505 B 1 02 08 1 14 13 27 53 68 L6U6 T 1 02 08 1 14 16 96 30 99 165 6 B 1 02 08 1 14 13 27 53 68 L7U7 T 1 25 06 1 16 13 19 60 05 1707 B 1 25 06 1 16 19 29 61 63 L8us T 6 08 41 1 45 68 77 25 43 6 08 41 1 45 51 47 92 99 L9U9 T 4 64 48 1 25 2 50 2 50 909 B 4 64 48 1 25 17 55 12 55 7 10 TRUSS RATING AND ANALYSIS PROGRAM TRAP PAGE 50 GROUP LOADING ANALYSIS TABLE 17 3 GROUP LOADING
16. 51 75 330 00 85 00 0401 13 360 00 59 30 360 00 85 00 0401 14 390 00 64 69 390 00 85 00 0401 15 420 00 67 92 420 00 85 00 0401 16 450 00 69 00 480 00 85 00 0401 17 480 00 67 92 480 00 85 00 0401 18 510 00 64 69 510 00 85 00 0401 19 540 00 59 30 540 00 85 00 0401 20 570 00 51 75 570 00 85 00 0401 21 600 00 42 05 600 00 85 00 0401 22 630 00 30 19 630 00 85 00 0401 22 660 00 18 17 660 00 85 00 0401 24 690 00 0 00 1 1 690 00 85 00 0401 25 720 00 18 31 720 00 85 00 0401 26 750 00 23 80 750 00 85 00 0401 27 780 00 46 47 780 00 85 00 0401 28 810 00 56 33 810 00 85 00 0401 29 840 00 63 37 340 00 85 00 9401 30 870 00 67 59 870 00 85 00 0401 31 900 90 62 00 0 1 900 00 85 00 0501 6501 i L lt 2 11 0038 00 66 750 65 420 33 L 0501 2L 2L 3 11 0038 00105 390105 390 33 r 0501 3L 3L 4 11 3038 00119 630119 630 33 1 0502 4L AL 5 11 1038 00127 890127 890 33 l 2502 5L 5L 8 11 D038 00135 980135 980 33 11 9501 6L 7 11 0038 00144 000144 000 33 l 7 34 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0502 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0502 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 7L 81 9L 101 111 121 13L 141 15L 16L 17L 18L 191 20L 211 221 23L 241 251 26L 27L 28L 29L 30L
17. III a lt 2 e A e ee MEMBER LCT W W L L F GROUP III GP I 0 3W WL LF 1 25 MAX MIN KIPS KIPS KIPS KIPS KIPS L1U2 30 96 2 61 4 14 177 79 280 34 U2L3 15 56 1 21 2 19 137 10 71 64 U3 L4 9 44 68 1 65 85 99 25 97 U4L5 5 62 40 1 48 62 61 4 37 15 U 6 1 08 09 68 19 99 8 42 0516 1 08 09 68 19 99 8 42 1607 5 62 40 1 48 62 61 4 37 L7U8 9 44 68 1 65 85 99 25 97 8179 15 56 1 21 2 19 137 10 71 64 U 9 110 30 96 2 61 4 14 177 79 280 34 7 11 SAMPLE PROBLEM 2 190 SIMPLE TRUSS WITH PRESTRESSED CABLES 7 12 EXAMPLE 2 DESCRIPTION Job Title 1 Span Prestressed Truss Bridge II General Information 1 Number of Spans 1 2 Number of Panel Points 10 3 Number of Truss Members 34 4 Span Length 189 72 III Loading Conditions 5 Uniform Loads Floor Steel 0 80 K f Slab W S 0 53 K f Railing and Curb 0 15 K f 6 Bracing Loads see Input Data Card 0702 7 AASHTO Live Load HS 15 8 Prestressed Cable Force Straight Cable 100 Kips One Drape Cable 100 Kips Two Drape Cable 50 Kips Output in the manual contains PL DL LL I Force Summary Table 10 7 13 jno e7 ssnil p ss ns idq 2 ldu ex3 7 14 INPUT DATA 7 15 0102 PRESTRESSED STEEL TRUSS BRIDGE 0103 19 5 16 57 36 19 5 16 57 36 30 25 5 36 34 5 29 32 36 28 5 24 22 36 34 5
18. LL INVENTORY ALLOWABLE STRESS FACTOR FOR TRUSS MEMBER Decimal Input the allowable stress factor to be used in the bridge Inventory Rating If left blank the system will use the standard AASHTO factor of 0 55 WSD ONLY AASHTO LL INVENTORY ALLOWABLE STRESS FACTOR FOR CABLE Decimal Input the allowable stress factor to be used in the bridge Inventory Rating If left blank the system will use the standard AASHTO factor of 0 6 WSD ONLY AASHTO LL OPERATING ALLOWABLE STRESS FACTOR FOR TRUSS MEMBER Decimal Input the allowable stress factor to be used in the bridge Operating Rating If left blank the system will use the standard AASHTO factor of 0 75 WSD ONLY AASHTO LL OPERATING ALLOWABLE STRESS FACTOR FOR CABLE Decimal Input the allowable stress factor to be used in the bridge Operating Rating If left blank the system will use the standard AASHTO factor of 0 9 INTERSTATE NO 0 YES 1 Integer If interstate tandem loading is to be considered for either analysis or rating input one 1 STATE VEHICLE POSTING VEHICLE ONE TWO THREE DESIGNATION Alphanumeric Input the code of the state vehicle for which a Posting Rating is required Up to three 3 state vehicles may be considered for a Posting Rating If less than three state vehicles are to be considered they should be 3 3 specified beginning with vehicle one designation Allowable state vehicle designations are given in Table 3 2 Allowable Live Load Typ
19. Maximum Live Load Force in Two Drape Cables Maximum Live Load Reactions Vertical Deflections These tables are generated for the Cable Option only Table A 1 Index of Output Tables OUTPUT LEVEL NO TABLE TITLE 1 2 3 LIVE LOAD TRUCK 1 Maximum Live Load Force in Lower Chords Maximum Live Load Force in Upper Chords Maximum LL Force in Additional Members Maximum Live Load Force in Vertical Members Maximum Live Load Force in Diagonal Members Maximum Live Load Force in Straight Cables Maximum Live Load Force in One Drape Cables Maximum Live Load Force in Two Drape Cables Maximum Live Load Reactions Vertical Deflections X X gt X LIVE LOAD TRUCK 2 Maximum Live Load Force in Lower Chords Maximum Live Load Force in Upper Chords Maximum Live Load Force in Additional Members Maximum Live Load Force in Vertical Members Maximum Live Load Force in Diagonal Members Maximum Live Load Force in Straight Cables Maximum Live Load Force in One Drape Cables Maximum Live Load Force in Two Drape Cables Maximum Live Load Reactions Vertical Deflections LL I These tables generated for Cable Option Table A 1 Index of Output
20. Tables OUTPUT LEVEL NO TABLE TITLE 1 2 3 LIVE LOAD TRUCK 3 Maximum Live Load Force in Lower Chords Maximum Live Load Force in Upper Chords Maximum Live Load Force in Additional Members Maximum Live Load Force in Vertical Members Maximum Live Load Force in Diagonal Members Maximum Live Load Force in Straight Cables Maximum Live Load Force in One Drape Cables Maximum Live Load Force in Two Drape Cables Maximum Live Load Reactions Vertical Deflections LL D p X X X gt LIVE LOAD TRUCK 4 Maximum Live Load Force in Lower Chords Maximum Live Load Force in Upper Chords Maximum Live Load Force in Additional Members Maximum Live Load Force in Vertical Members Maximum Live Load Force in Diagonal Members Maximum Live Load Force in Straight Cables Maximum Live Load Force in One Drape Cables Maximum Live Load Force in Two Drape Cables Maximum Live Load Reactions Vertical Deflections LL D X X X lt These tables are generated for the Cable Option only Table A 1 Index of Output Tables OUTPUT LEVEL NO TABLE TITLE 1 2 3 10 0 LIVE LOAD DL LL I AASHTO LOADING 10 1 DL LL I Force Summary for Lower Chord Members 10 1A PL DL LL I Force Summary for Lower Chord Members 10 2 DL LL I Force Su
21. loads which are given as concentrated panel point loads are used to describe wood bracing DL or any miscellaneous loads which may occur These may be placed on any or all of the points of the truss 2 4 LIVE LOADING TRAP automatically determines the maximum compressive and tensile forces for all truss members and cables if any maximum downward and upward reactions and maximum deflections at each lower panel point They are obtained by applying the AASHTO lane and specified H or HS truck loadings the interstate vehicle AASHTO LRFD HL 93 loading AREA Cooper E40 to E80 and any truck configuration specified by the user These are all activated together or separately at the option of the user Some special features regarding the application of live loadings are as follows 1 The distribution factor may be input or else it is automatically generated by the program 2 The LL can be applied at the top chord panel points at the bottom chord panel points or intermediate in a vertical member 3 The impact factors are obtained considering loaded lengths such as required by AASHTO for continuous beam bridges see Methodology Section 5 3 4 25 LOAD COMBINATIONS The combinations of loads employed by TRAP utilize the working stress criteria load factor criteria and load and resistance factor criteria and incorporate the AASHTO specifications to define different combinations of loads There are seven groups representing various combinat
22. structure analyzed according to the standard working stress method No other live load analyses can be made during the same run and no rating information will be given Rating Only This option indicates that at least one rating analysis will be performed Rating types vehicles and allowable stresses are given on data types 0301 0302 and 0303 All vehicles given will be applied automatically and the structure rated accordingly for each one Input Verification Only This option allows the scan of all input data for possible errors This affords the user a visual check of the truss structure definition Combinations of Loads Only This option performs the combinations of loads according to the AASHTO definitions shown in Table 5 1 The results of every group loading and the critical group for all member forces will be shown in this option Prestressing option should be 0 in this option i e no group loading for prestressed truss 3 12 Table 3 2 Allowable Live Load Types DESCRIPTION AASHTO LIVE LOADING DATA TYPE 0301 INPUT LOADING DESIGNATION H 10 H 15 H 20 HS 15 HS 20 or HL 93 CONFIGURATION As given by the 2003 AASHTO Standard Specification for Highway Bridges and ASHTO LRFD Bridge Specifications 6 Edition with 2013 Interim STATE VEHICULAR LOADING DATA TYPE 0301 Any 9 Character Alphanumeric As requested by user cards 0304 0305 0306 The catalog
23. which allows great flexibility in the type of structure which can be accommodated The specific structural features which can be accommodated and several assumptions are described as follows 1 Bridges which are either statically determinate or indeterminate 2 Bridges which are either deck or through trusses or a combination of both 3 Members may have flanged or box sections 4 The material is assumed to obey Hooke s Law and the structural displacements are assumed small 5 All joints are assumed pinned 6 Dummy members are assumed to have no axial stiffness 7 The deck may be attached to vertical members see Chapter 5 0 Methodology 8 The truss can be prestressed with different cables and the program is capable of analyzing the prestressed truss 9 Cables can be in tension only 2 3 DEAD LOADING All loadings due to dead load DL are computed and applied automatically by the program from basic input information The approximations and assumptions used are described as follows 1 The dead load for the steel of the truss structure is computed from the sections input times a detail factor to account for the structural details such as 2 1 bolts gusset plates etc 2 Uniform loads are used to define the floor steel slab and wearing surface railing and curb and utilities and accessories These are given in intensity per linear length and may be composed of up to nine segments of different intensities 3 Dead
24. 0 61 250 60 020 10 7032 00 61 250 60 020 10 7032 00 47 250 42 530 10 7032 00 47 250 47 250 10 7032 00 47 250 46 300 11 0032 00 65 250 65 250 11 0032 00 85 130 85 130 11 0032 00100 890100 890 11 0032 00112 740112 740 11 0032 00120 240120 240 11 0032 00120 210120 240 11 0032 00112 740112 740 11 0032 00104 660104 660 11 0032 00 88 890 88 890 10 7032 00 54 750 54 200 10 7032 00 47 250 47 250 1 9025 38 27 940 27 940 3 0425 38 37 440 37 440 3 0425 38 37 440 37 440 3 0425 3B 37 440 37 440 3 4825 38 41 440 41 440 4 9825 38 45 380 45 380 7 35 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 He PRR HH P HH fp p n e pp a a 1 1 1 1 1 1 1 1 H eHe 4 H pr ps po 0501 0501 0501 0501 0501 0501 0501 0502 0501 0501 0501 0501 0501 0501 0501 0501 0501 0561 0501 0501 0591 0501 0591 0501 0503 0501 0501 0501 0501 6501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 0501 9501 9501 9501 0501 0601 0601 0602 0602 0603 au 3U 100 11 120 130 140 15U 16U 170 18U 190 200 210 22U 220 24U 25U 26U 2711 2811 29U 300 31U 10 20 40 50 eu 7U 81 9L 101 111 12L 13L 14L 15L 160 170 1810 191 201 21U 22U 23U
25. 17 HS L7US 63 03 39 29 L 25 41 102 22 L 37 62 H5 1809 11 87 48 79 14 06 HS 69 66 L 2 20 HS 238 29 00 56 09 L 238 29 334 38 L TRUSS RATING AND ANALYSIS PROGRAM TRAP PAGE 42 PRESTRESSED STEEL TRUSS BRIDGE TABLE 10 6 PI LI I FORCE SUMMARY FOR STRAIGHT CABLES AASHTO LOADING RESULTS MAXIMUM MAXIMUM MAXIMUM MINIMUM PRE TENSION COMPRESSION CABLE FORCE CABLE FORCE CABLE STRESS m og IDAD LIFE TYPE K K K K L1L3 100 00 2 71 L 00 202 71 100 00 7 21 TRUSS RATING AND ANALYSIS PROGRAM TRAP PAGE 43 PRESTRESSED STEEL TRUSS BRIDGE TABLE 10 68 FI LLHI FORCE SUMMARY FOR ONE DRAPE CABLES AASHTO LOADING RESULTS MAXIMUM MAXIMUM MAXIMUM MINIMUM PRE TENSION COMPRESSION CABLE FORCE CABLE FORCE CABLE STRESS LOAD II I II I PL LI I PLELLHI X 9 K K 171809 100 00 2 68 L 18 HS 102 68 L 99 82 HS TRUSS RATING AND ANALYSIS PROGRAM TRAP PAGE 44 PRESTRESSED STEEL THUSS BRIDGE TABLE 10 6C PIALIAI FORCE SUMMARY FOR TWO DRAPE CABLES AASHTO LOADING RESULTS MAXIMUM MAXIMUM MAXIMUM MINIMUM FRE TENSION COMPRESSION CABIE FORCE CABLE FURCE CABLE STRESS M LOAD TYPE LIAI TYPE TYPE K K K U3L4L6U 50 00 2 33 HS 00 52 33 HS 50 00 7 22 SAMPLE PROBLEM 3 3 SPAN CONTINUOUS DECK TRUSS 7 23
26. 2 3 7 CABLE DATA FIG 3 5 If the prestressing option in Data Type 0103 is set equal tol at least one of the following cable data cards should be input If the prestressing option is 0 no cable data type should be input Data Type 0502 Straight Cable Data Fig 3 5a CABLE NO Integer The straight cable sequence number starting with 1 and ending with the total number of straight cables CABLE LOCATION AND DESIGNATION Alphanumeric The designation of each cable with respect to the panel points Fig 3 6a Examples include L4U5 A1U2 L5US etc There are four fields 2 alphas of 1 space each and 2 numerics of 3 spaces each The numeric fields should be right justified if less than three digits CABLE AREA NET SQ IN or mm2 Decimal The net area of the straight cable YIELD STRESS KSI or MPa Decimal The yield stress of the material used as given by the AASHTO specifications PRESTRESS FORCE KIPS or KN Decimal Input the prestress force used in prestressing the cable INFLUENCE LINE OPTION Integer An option which will allow the user to select which member influence line will be output 1 Input 0 or leave blank if no influence line output is desired 2 Input 1 if a table of influence line values for the given member is to be output Data Type 0503 One Drape Cable Data Fig 3 5b CABLE NO Integer The one drape cable sequence number starting with 1 and ending with the total number of one drape cables C
27. 6 3 in Equation 6 1 and rearranging Equation 6 1 results in Tr amice uA A 6 4 6 2 By solving Equation 6 4 the cable cross sectional area required is E f 6 5 Substituting Equation 6 5 in Equation 6 3 the required prestress stress for the cable is E n T A f f CTS T 1 2 Since the prestress force be calculated PL fei is Ac 6 7 then P eg oq eos Tp Aa f 7 fa _ BOMBE WW T T A f CIO PA Equations 6 5 and 6 8 still can be used as a guide to start with for statically indeterminate trusses as a trial and error method is required to reach a solution 6 3 6 2 RATING OF PRESTRESSED CABLES The TRAP system has the capability to determine the structural rating for the prestressed cables used in prestressing the deficient truss automatically if the rating option is specified in the program TRAP will rate the cable for inventory operating and posting AllowableCable Stress P Stress Cable Rating Factor idu Actual Cable LL I Stress 6 9 where P is the prestressing stress used in pretensioning the cable The allowable cable stress for each type of cable rating is calculated by the formula F FI Fy 6 10 where F the allowable cable stress FI the allowable rating stress factor the yield stress for cable The default allowable rating stress factor for prestressed cable are as follows for inventory 0 6 for operating 0 9 for posting 0
28. 60 41 030 34 730 34 730 41 030 43 560 41 030 36 570 43 090 44 520 45 430 46 430 44 520 36 570 34 730 36 690 44 060 62 970 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 35 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 PRE PRE epa a a F k He LI i 1 1 1 l 1 1 1 1 1 1 1 1 11 1 1 1 l 1 1 l 1 1 1 1 1 1 1 1 0603 1 0 4820 0 06 00 00 9761 0701 1 5 4 2 6 7 3 7 14 6 3 5 8 8 6 10 4 7 10 8 8 20 0 9 10 810 10 4 070111 2 912 6 313 7 414 7 036 6 716 hos RIVA 7 01898 7 420 6 3 070121 6 922 13 423 10 524 20 025 26 826 10 427 8 828 6 329 7 130 6 7 070131 5 4 0702 0702 1 0 72 0 03 0 64 0 05 2 46 3 9 7 4 2 8 12 19 4 210 4 0 070211 2 512 0 012 1 114 6 815 0 016 0 717 0 018 0 819 1 120 0 0 070221 2 522 4 022 4 224 12 125 4 226 3 927 2 428 0 029 0 830 0 0 070251 0 7 7 37 APPENDIX A INDEX OF OUTPUT TABLES Table A 1 Index of Output Tables OUTPUT LEVEL NO TABLE TITLE 1 2 3 INPUT VERIFICATION System Input General Live Load and Rating Data Special Live Load Data State Vehicular Data Panel Point Data Member Data Straight Cable Data One Drape Cable Data Two Drape Cable Data 1 7 Uniform Dead Load
29. 7 10 3 15 6 10 3 10 3 10 3 10 3 15 6 10 3 35 25 14 7 10 3 10 3 10 3 10 3 10 3 10 3 14 7 35 25 7 6 23 0 16 57 36 16 57 36 25 5 36 29 32 36 24 22 36 29 32 36 25 5 36 16 57 36 16 57 36 24 37 36 27 5 36 30 36 30 36 30 36 27 5 36 24 37 36 8 75 36 13 26 36 8 75 36 8 75 36 8 75 36 8 75 36 13 26 36 8 75 36 30 36 12 5 36 8 75 36 8 75 36 8 75 36 8 75 36 8 75 36 8 75 36 12 5 36 30 36 HHHOOOOHHHHHOOO O H H H H H pt pt pt pa t pa pt E cou le ee ta eiie OOOUUUUOOOOOUUUUOOCOOOOOoOoO0Oo0oooooooo e 8 9 26 25 00000000000000000 M ro 1 2 OUTPUT RESULTS TRUSS RATING AND ANALYSIS PROGRAM TRAP PAGE 1 CONFORMS TO 1983 AASHTO SPEC UP TO 1987 INTERIM EXCLUDING LOAD FACTOR DESIGN EXAMPLE NO 1 STATICAL INDETERMINATE TRUSS GROUP LOADING ANALYSIS ALL INFORMATION PRESENTED IS FOR REVIEW APPROVAL INTERPRETATION AND APPLICATION BY A REGISTERED ENGINEER ONLY a a ee A
30. 9 6 4 7 0 SAMPLE PROBLEMS This document includes three sample problems that can be used as learning tools Each sample contains a problem description sketch of the truss list of input and partial output Of the three samples the third includes a completed input form for a guide to data preparation The installation package distributed with the manual contains complete input and output of all sample problems The users may choose to review the input data from the installed directory in order to test the programs that they will install on any PC or PC compatible 7 1 SAMPLE PROBLEM 1 190 SIMPLE TRUSS 7 2 EXAMPLE 1 DESCRIPTION I Job Title 1 Span Truss Bridge II General Information 1 Number of Spans 1 2 Number of Panel Points 10 3 Number of Truss Members 34 4 Span Length 189 72 ft III Loading Conditions 1 Uniform Loads Floor Steel 0 80 K f Slab W S 0 53 K f Railing and Curb 0 15 K f 2 Bracing Loads See Input Data Card 0702 3 AASHTO Live Load HS 15 4 Group Loading See Input Data Cards e Output in the manual contains Group Loading III for Table 17 3 7 3 017 8 68011 80 12 D sieued 6 1 ejdwex3 74 INPUT DATA 7 5 0101 NO 1 0101 STATICAL INDETERMINATE TRUSS 0102 GROUP LOADING ANALYSIS 0103 0103 0104 3 0104 189 72 0301 4 0301HS 15 55 0 HS 15 0401 0401 0401 0401 0401 0401 0401 0401 0401
31. ABLE LOCATION AND DESIGNATION Alphanumeric The designation of each cable with respect to the panel points Fig 3 6b Examples include L4U5L6 A1U2L5 50516 etc There are six fields 3 alphas of 1 space each and 3 numerics of 3 spaces each The numeric fields should be right justified if less than three digits CABLE AREA NET SQ IN or mm Decimal The net area of the cable YIELD STRESS KSI or MPa Decimal The yield stress of the material used as given by the AASHTO specifications PRESTRESS FORCE KIPS or KN Decimal Input the prestress force used in prestressing the cable INFLUENCE LINE OPTION Integer An option which will allow the user to select which member influence line will be output 1 Input 0 or leave blank if no influence line output is desired 2 Input 1 if a table of influence line values for the given member is to be output Data Type 0504 Two Drape Cable Data Fig 3 5c CABLE NO Integer The two drape cable sequence number starting with 1 and ending with the total number of two drape cables CABLE LOCATION AND DESIGNATION Alphanumeric The designation of each member with respect to the panel points Fig 3 6c Examples include 14050617 A1U2U3L4 etc There are eight fields 4 alphas of 1 space each and 4 numerics of 3 spaces each The numeric fields should be right justified if less than three digits CABLE AREA NET SQ IN or mm Decimal The net area of the cable YIELD STRESS KSI
32. Cables 4 4 0X gt gt gt gt These tables generated for Cable Option Table A 1 Index of Output Tables OUTPUT LEVEL NO TABLE TITLE 1 2 3 12 0 LIVE LOAD DL LL D TRUCK 2 121 DL LL I Force Summary for Lower Chord Members 12 1A PL DL LL I Force Summary for Lower Chord Members 192 DL LL I Force Summary for Upper Chord Members 12 2A PL DL LL I Force Summary for Upper Chord Members 12 3 DL LL I Force Summary for Additional Members 12 3A PL DL LL I Force Summary for Additional Members 124 DL LL I Force Summary for Vertical Members 12 4A PL DL LL I Force Summary for Vertical Members 12 5 DL LL I Force Summary for Diagonal Members 12 5A PL DL LL I Force Summary for Diagonal Members 12 6A PL LL I Force Summary for Straight Cables 12 6B PL LL I Force Summary for One Drape Cables 12 6C PL LL I Force Summary for Two Drape Cables X X X X X X X X X X X X X X X X X X X X X X X X X X X gt lt X These tables are generated for the Cable Option only Table A 1 Index of Output Tables OUTPUT LEVEL NO TABLE TITLE 1 2 3 LIVE LOAD DL LL I TRUCK 3 DL LL I Force Summary for Lower Chord
33. DISTRIBUTION Straight tendon b One drape tendon c Two drape tendon represents end anchorage FIG 3 5 PRESTRESSING CABLE TYPEES 3 18 a Configuration of Truss 1 with Straight Cable b Configuration of Truss 1 with One Drape Cable NN L c Configuration of Truss 1 with Two Drape Cable FIG 3 6 CONFIGURATION OF TRUSS EXAMPLES WITH VARIOUS TYPES OF CABLE Load No 1 Load No 2 Load No 3 Z Ss AA emt CENE M NL i 80 120 FIG 9 7 SEGMENTED UNIFORM LOADS FIG 3 8 PANEL POINT LOADS 40 OUTPUT 4 1 GENERAL Various engineering and diagnostic levels of output are available These depend upon the output level specified and whether an analysis rating of the truss prestressed or not or combinations of loads is being performed All output is given in the form of tables identified by number and title Appendix A Index of Output Tables gives a listing of all program output tables and indicates under what OUTPUT LEVEL DATA TYPE 0103 and for which function Analysis Rating or Combinations of Loads each table is given 4 2 RATING AND ANALYSIS OUTPUT The various tables available for truss analysis rating and load combinations are described in Appendix B Definition of Output Tables Given for each output table is the actual output heading along with a definition of each item that appears in that heading 43 OPTIONAL PROGRAM OUTPUT
34. Data 1 8 Bracing Dead Load Data 1 9 Miscellaneous Load Data 2 0 TRUSS GEOMETRY DEFINITION 2 1 Truss Heights 22 Geometric Data for Lower Chord Members 2 3 Geometric Data for Upper Chord Members 2 4 Geometric Data for Additional Members 2 5 Geometric Data for Vertical Members 2 6 Geometric Data for Diagonal Members These tables are generated for the Cable Option only Table A 1 Index of Output Tables OUTPUT LEVEL NO TABLE TITLE 1 2 3 TRUSS DEAD LOAD Dead Loads at Lower Panel Points Total Dead Load and Prestress Load at Lower Panel Points Dead Loads at Upper Panel Points Total Dead Load and Prestress Load at Upper Panel Point Dead Load at Additional Point A Total Dead Load and Prestress Load at Additional Point Dead Load at Additional Point B Total Dead Load and Prestress Load at Additional Point B X gt gt gt Dead Load Deflections Lower Panel Point Deflections Dead Load and Prestress Deflections Lower Panel Point Deflections Dead Load Deflections Upper Panel Point Deflections Dead Load and Prestress Deflections Upper Panel Point Deflections Dead Load Deflections at Additional Point A Dead Load and Prestress Deflections at Additional Point A Dead Load Deflections at Additional Point B Dead Lo
35. ESTRESSED CABLES Prestressing truss bridges is a means of creating redundancy i e alternate load paths in the structural system and strengthening it Consequently structural strength and reliability can be increased Since prestressing enlarges the elastic range increases the fatigue resistance reduces deflection and increases redundancy the remaining life of the truss bridge can therefore be increased relatively inexpensively The method used in the development of the stiffness matrix of a prestressed plane continuous truss bridge is based on the following three assumptions The material of the cables is linearly elastic and perfectly plastic all calculations involving the overall dimension of the truss can be based upon the original dimension of the structure and the axial cable force is constant throughout the length of the cable i e friction between the cables and their paths is zero Three cable layouts are considered in this study a straight cable a one drape cable and a two drape cable A draped cable can be constructed by passing the cable over a pulley attached to the truss joint where the cable needs to change its angle as shown in Figure 3 5 It is assumed that the friction between the pulley and the cable passing over it is negligible and the cable will be in tension only 6 1 ANALYSIS OF PRESTRESSED CABLES The derivation of the cable stiffness matrix is based on the direct stiffness method Every cable layout i
36. EXAMPLE 3 DESCRIPTION I Job Title 3 Span Continuous Deck Truss Bridge II General Information 1 Number of Spans 3 2 Number of Panel Points 31 3 Number of Truss Members 121 4 Total Number of Released Members 3 5 Span Length Span No 1 210 00 Span No 2 180 00 Span No 3 210 00 III Loading Conditions 1 Uniform Load Floor Steel 0 95 K f Slab W S 0 56 K f Railing and Curb 0 48 K f 2 Bracing Loads see Input Data Card 0701 and 0702 3 AASHTO Live Load HS 20 4 State Vehicular Loading 4S1 5C3 6T1 7 24 5 Special Truck Loading S 20 40 Output in the manual contains Rating Summary for Table 16 7 25 os 80 01 C ON N d5 C ON HY4Ss 4007 01Z7 00 DEBZ 00 081 00 0 84 921 Q0 0 ANLYa 009 521 217 vin cn ac sen 4007 08 5 Z ON NYdS 007 012 ION A dS 00 10124 00 0681 0682 400 0817 00 0509 00 9 WhL d 0940 H LY OIT SI il I Zi n an n 91 s n en vil 7 26 08 5355144 avol ANYS Au ISX sz 02 11 ALISILSYIA 5 01140 SNOIIdO ALISNAaLNI GNIM SOIODON 116816 1 41 0 114185531 3HvN 321623X3 7
37. MBINATION OPTION Integer If 1 is specified AASHTO truck with its distribution factor as defined in Data Type 0104 or calculated by the program will combine with Overload Special vehicle with the distribution factor that is defined below SPECIAL VEHICLE DISTRIBUTION FACTOR Decimal If a combination of AASHTO and Overload trucks is considered this distribution factor will be applied to the Overload Therefore it is recommended to compute the distribution factor with only the near lane loaded The program then assumes the near lane is occupied by Overload and the other lanes are loaded by AASHTO trucks with multilane reduction considered Data Type 0303 Special Vehicle Axle Weights and Spacings AXLE NO Integer Input the sequence number of the axle beginning with one 1 AXLE WEIGHT KIPS or KN Decimal Input the weight of the axle SPACING NO Integer Input the number of the nth spacing between the nth and nth 1 axles SPACING DISTANCE FT or m Decimal Input the nth distance between the nth and nth 1 axles 3 4 STATE VEHICLE DATA Data Type 0304 State Vehicle One Axle Weights and Spacings AXLE NO Integer Input the sequence number of the axle beginning with one 1 AXLE WEIGHT KIPS or KN Decimal Input the weight of the axle SPACING NO Integer Input the number of the nth spacing between the nth and nth 1 axles SPACING DISTANCE FT or m Decimal Input the nth distance between the nth and nth 1 axles Data Type 0305 an
38. Members PL DL LL I Force Summary for Lower Chord Members DL LL I Force Summary for Upper Chord Members PL DL LL I Force Summary for Upper Chord Members DL LL I Force Summary for Additional Members PL DL LL I Force Summary for Additional Members DL LL I Force Summary for Vertical Members PL DL LL I Force Summary for Vertical Members DL LL I Force Summary for Diagonal Members PL DL LL I Force Summary for Diagonal Members PL LL I Force Summary for Straight Cables PL LL I Force Summary for One Drape Cables PL LL I Force Summary for Two Drape Cables X gt lt lt 0X gt gt LIVE LOAD DL LL I TRUCK 4 DL LL I Force Summary for Lower Chord Members PL DL LL I Force Summary for Lower Chord Members DL LL I Force Summary for Upper Chord Members PL DL LL I Force Summary for Upper Chord Members DL LL I Force Summary for Additional Members PL DL LL I Force Summary for Additional Members DL LL I Force Summary for Vertical Members PL DL LL I Force Summary for Vertical Members DL LL I Force Summary for Diagonal Members PL DL LL I Force Summary for Diagonal Members PL LL I Force Summary for Straight Cables PL LL I Force Summary for One Drape Cables PL LL I Force Summary for Two Drape Cables These tables are generated for the Cable Option only
39. OIL asas qana do oA Sai Fate da c Foedus 3 10 3 10 Miscellaneous Panel Point Loads 3 11 40 L eo do a 4 4 1 sa nu dete od atta io dite 4 1 4 2 4 Rating and Analysis Output 4 1 4 3 Optional Program Output 4 1 5 0 Methodology A 5 1 5 1 Structural Analysis of Trusses 5 1 52 Dead LR Qa a M Saa u ae 5 1 5 3 Live Load 5 2 5 4 Combinations of Loads 5 4 5 57 Rating WSR 5 5 5 6 Ratne LFR orrLRFR S N ode eee 5 9 6 0 Methodology of Prestressed Cables 6 1 6 1 Analysis of Prestressed Cables 6 1 6 2 Rating of Prestressed Cables 6 4 7 0 Sample Problems 7 1 7 1 Sample Problem 1 190 Simple Truss 7 2 132 Sample Problem 2 190 Simple Truss with Prestressed Cables 7 15 7 3 Sample Proble
40. TRAP TRUSS RATING AND ANALYSIS PROGRAM e B idge Engineering Software amp Techno Bridge Engineering Software amp Technology BEST Center Department of Civil and Environmental Engineering University of Maryland College Park MD May 2014 TRAP USER MANUAL Table of Contents Page List oP Tables oM ATA a iii Listo f FRISWPeS M b uite iii sag iv 1 0 Using WIN TRAP 00 pde 1 1 1 1 dass 1 1 1 2 Accessing the Main Menu A A 1 1 1 3 The TRAP Main eint oed Gane edi aaah 1 2 1 4 Detailed Usage of the Utility Program 1 2 2 0 o eM ue ttd ee use 2 1 2 1 HQ 2 1 2 2 Str ct ral Mod l a s ds 2 1 2 3 Dead d 2 1 24 Live 2 2 2 5 Load Combination u Saa Foe Re reden 2 2 2 6 aqui 2 3 2 7 PHC SUES SIMU os 2 4 3 0 PU di 3 1 3 1 tas 3 1 3 2 Live Load and Rating Data 3 3 3 3 Special Vehicle danna 3 4 3 4 State Vehicle id 3 5 3 5 deoa 3 5 3 6 Member Data ido 3 6 3 7 Cable Data us 3 8 3 8 Uniform Dead 3 10 3 9 Panel P
41. VduV YILENIH 3248 025 NOI1V201 m WOWIN IW 2 3 j 40 07 VIVO WiHW3h 7 31 4394 uU ANT 404 1311 1819 55 UN 7 5 14 01 3904134 AUOJINN 1441 howd 1511 1331 32NVISIO HYUOJINA viva dvo avid 7 32 Sul iN YO iv Sd 13 qvo 81 SdI3 qvo qvo LINIOJ 19NYd 434807 OL 30 Savol 1 33 0101SUMMIT NORTH 0101 TRAP MAIN ST BRIDGE O102SPAN DECK CANTILEVER TRUSS 0103 0103 3 2 29000 a 0104 0104210 000480 000210 000 2 0250 40 000 1 200 0301 0301 5 20 HS 29 1 451 5C3 STL 0 75 0302 0302 TZST TEST VEHICLE 0 55 0303 0303 2 12 000 1 13 875 2 16 050 2 4 250 3 16 050 0304 0304 i 10 000 1 15 000 2 16 000 2 4 000 3 16 000 3 4 000 4 16 000 0505 0305 1 8 000 1 12 000 2 16 000 2 4 000 3 16 000 3 21 000 4 20 000 4 10 000 0305 S 20 000 0306 0306 1 10 000 1 13 000 2 16 000 2 4 000 3 16 000 3 4 000 4 16 000 4 10 000 0306 5 11 000 5 16 000 6 11 000 0401 0401 1 0 00 69 00 Q 1 0 00 85 00 0401 2 30 00 67 59 30 00 85 00 0401 3 60 00 63 37 60 00 85 00 0401 4 90 00 56 33 90 00 85 00 0401 5 120 00 46 47 120 00 85 00 0401 6 150 00 33 80 150 00 85 00 0401 7 180 00 18 31 180 00 85 00 0401 8 210 00 0 00 1 1 210 00 85 00 0401 9 240 00 16 17 240 00 05 00 0401 30 270 00 30 19 270 00 85 00 0401 11 300 00 42 05 300 00 85 00 0401 12 330 00
42. ability of this program includes automatic determination of the maximum compressive and tensile forces for all truss members as well as prestressed cables if any maximum upward and downward reactions and the maximum deflection at each lower panel point These are determined by applying AASHTO lane specified H or HS truck or HL 93 LRFD design vehicle and generalized truck loadings to the appropriate member reaction or deflection influence line The specific assumptions and methodology are as follows 1 2 3 Distribution Factor The distribution factor may either be input directly or it may be generated automatically by the program If the latter case is desired the width between curbs or the width between trusses must be input Here the number of traffic lanes is determined in accordance with AASHTO The width of a design traffic lane is computed from the width between curbs divided by the number of traffic lanes It is assumed that the lane loadings or standard trucks can occupy any position within their individual design traffic lane in computing the maximum distribution factor Loads Standard AASHTO highway loadings including truck lane and tandem are used in the program Also included are specific state trucks incorporated into the system as desired by the user and any generalized truck Application of Loads The calculation of live load effects requires three phases of program operation The first phas
43. ad and Prestress Deflections at Additional Point B Dead Load Forces and Adjusted Lengths in Lower Chords DL PL Forces and Adjusted Lengths in Lower Chords These tables are generated for the Cable Option only Table A 1 Index of Output Tables OUTPUT LEVEL NO TABLE TITLE 1 2 3 DL Forces and Adjusted Lengths in Upper Chords DL PL Forces and Adjusted Lengths in Upper Chords DL Forces and Adjusted Lengths in Additional Members DL PL Forces and Adjusted Lengths in Addtl Members DL Forces and Adjusted Lengths in Vertical Members DL PL Forces and Adjusted Lengths in Vertical Members DL Forces and Adjusted Lengths in Diagonal Members DL PL Forces and Adjusted Lengths in Diag Members Dead Load Reactions Dead and Prestressing Loads Reaction Total Truss Steel Weight lt gt gt lt gt gt gt X OUTPUT LANE FACTOR Member Influence Line Values Cable Influence Line Values Reaction Influence Line Values LIVE LOAD AASHTO LOADING Maximum Live Load Force in Lower Chords Maximum Live Load Force in Upper Chords Maximum Live Load Force in Additional Members Maximum Live Load Force in Vertical Members Maximum Live Load Force in Diagonal Members Maximum Live Load Force in Straight Cables Maximum Live Load Force in One Drape Cables
44. ance Factor LRFD methods which are based on the following criteria 1 Load and Resistance Factor Design LRFD Rating based on the AASHTO Manual for Bridge Evaluation 2nd Edition with up to 2014 Interims 2 National Bridge Inventory NBI Rating based on AASHTO Manual for Condition Evaluation of Bridges 1994 and updated Interims 274 edition 3 Load Factor LFD Rating based on the AASHTO Guide Specifications for Strength Design of Truss Bridges Load Factor Design 1986 and updated Interims 4 New Load and Resistance Factor Design LRFD based on the AASHTO LRFD Bridge Design Specifications 6 Edition with 2013 Interim Revisions Note The WINDOWS upgrade for the V6 00 Series version is called WIN V 1 00 In Version 6 00 both English and SI units are allowed iv TRAP 1 0 USING WIN TRAP WIN TRAP currently is available for use on microcomputers using the Microsoft Windows environment This manual describes the Windows version of WIN TRAP hereafter referred to as TRAP This version utilizes a Windows based pull down menu structure to access TRAP s input execution graphic and printing utilities 1 1 Before You Begin TRAP is designed to run on microcomputers that use the Microsoft Windows operating system While this manual provides step by step instruction in the use of TRAP it cannot address the specific operation of every personal computer PC Before you begin please ask yourself the following questi
45. can safely pass across the bridge without overstressing any structural member A factor less than one indicates overstressed members and may result in a weight limit being specified for the bridge structure Since dead load stresses are constant for every member and the allowable stress does not change for each type of rating this rating factor is the lowest value obtained through the highest possible live load effect for each member Computation of dead and live load stresses has been discussed in Sections 5 1 and 5 2 In the process of determining the allowable stress total stresses are calculated to decide whether the member is in tension or compression The allowable stresses for inventory operating and posting rating are calculated as given below 1 Inventory Rating a Truss member in tension Fir min FyAg FuAnU Ag 5 2 b Truss member in compression C QE F 2 5 3 When KL r lt 4 5 4 When KL r gt C 5 5 IR KL iw vot Where F IR the allowable stress for Inventory Rating Es the yield strength of the member E the modulus of elasticity K the effective length factor r the minimum radius of gyration L the member length Frr the allowable tension stress factor for inventory rating default 0 55 Fic factor of safety of compression member for inventory rating default 2 12 otherwise 2 12 0 75 1 7 2 Operatin
46. cess any of the five utilities in TRAP or to exit the program These are the Input Run Graphic Print and Help utilities Input Utility allows you to create new bridge data files or to edit existing files Once you have entered the details of a structure then you can save it for later use Run Utility allows you to execute the TRAP program using the data stored in any of your input data files Graphic Utility allows you to view and print graphic files Print Utility allows you to view and print output files and tables It also provides a directory of available tables for your convenience Exit allows you to exit TRAP simply by clicking on the word Exit in the TRAP Main Menu or by typing Alt x on your keyboard Help Utility allows you to view help for the Help basics commands and buttons Help Utility also may be accessed from Input Utility 1 4 Detailed Usage of the Utility Programs Input Utility is accessed by clicking on the Input in the main menu It allows you to create new bridge data files or to edit existing files Once you have entered the details of a structure you can then save it for later use To open a data file On the File menu click Open In the Look in box click the drive that contains the file Below the look in box click the folder that you want Double click the data file or type it in the File Name box create new data file On the File menu click New T
47. d 0306 See 0304 for State vehicles two and three Data Type 0307 and 0308 See 0302 and 0303 for Special Vehicle Overload two 3 5 PANEL POINT DATA Data Type 0401 Panel Point Data PANEL POINT NO Integer The number of each panel point and subdivision in the planar truss starting with the one at the extreme left bridge support LOWER UPPER A and B PANEL POINTS X and Y COORDINATES FT or m Decimal Input the X and Y coordinates of all panel points NOTE The coordinate system should be positioned such that all panel points are positive and lie in the first X Y quadrant see Figure 3 1 In addition to the upper and lower panel points the capability exists within TRAP to define two extra panel points A and B see Figure 3 1 RESTRAINTS X and Y Integer The definition of the support restraints at the panel point locations in the X and Y directions Use 1 if the panel point is restrained in the X or Y direction For example if the support is pinned use for both directions if roller use 1 for Y direction and 0 for X direction NOTE Care should be taken when specifying support restraints Every structure must be restrained 3 5 from moment in the X and Y direction and therefore must contain at least 1 pinned point and 1 roller point NOTE In order to identify whether the first upper or lower panel point exists while inputting for the Data Type 0401 Panel Point Data the user should be careful about the first panel p
48. data file is selected To select a different output file click the Output File button then follow the same procedures To execute TRAP Clicking the OK button on the run utility screen will execute TRAP After the execution starts a separate window will appear on the screen with the program status shown Print Utility To change printers and printing options 1 On the Print menu click Print Setup 1 4 2 To change printers paper size or page orientation make the appropriate modifications 3 Click OK Print screen On the Print menu click Print Screen Print Utility is accessed by clicking on Print in the main menu It allows you to view and print output files and tables It also provides a directory of available tables for your convenience To open a result file Click the drive that contains the file Click the directory folder that you want Double click the file in the file list box or type it in the file name box Click OK To view the whole result file Click the View Print File tab to view the whole file To find a string 1 Click Find String 2 In the Enter Search String box enter the text you want to search for 3 Click OK To find next string Click Find Next to search the next string To print the whole result file 1 Click the Print button 2 Chose a printout option 3 Click OK To change printing options 1 Click Print Setup 2 To change printers paper size
49. e involves the generation of influence lines for each member and reaction as well as for prestressed cables if any If the deck is attached to any vertical member it is assumed that the unit load is shared by the upper and lower joints as shown in Figure 5 1 After the application of unit loads the resulting ordinates are then stored 5 2 The second phase of load application involves the extraction of basic data from the influence lines These include maximum and minimum ordinates positive and negative areas and loaded lengths of all influence lines The third and final phase involves the application of live loads to obtain maximum member forces and reactions as well as cable forces if any This is accomplished as follows a With respect to application of AASHTO live loading two concentrated loads are used for moment computations These are used to obtain maximum upper chord tension and lower chord compression However only one concentrated load for moment is used throughout for all other truss members except for diagonals where the concentrated load for shear is used In order to obtain maximum reactive forces one concentrated AASHTO shear load is used For maximum lower panel point deflections one concentrated AASHTO load for moment is used b With respect to truck loading the maximum member forces as well as maximum cable forces reactions and lower panel point deflections are obtained by placing and reposi
50. embers also as shown in Equations 5 3 through 5 5 without Fic factor For LFR Capacity is and for Capacity is where is the resistance factor Capacity reduction factor DL Force 15 the factored dead load axial force tension or compression and expressed as where is the dead load factor and Fpr is the calculated dead load force LL I Force is the factored live load plus impact axial forces tension or compression and expressed as yr Fri where is the live load factor and may be varied according to their truck definition normal load or overload and Fir 15 the calculated live load force plus the impact effect Axial Tension P gt Pa P F A where 2745 51 lesser LRFD Eq 6 8 2 1 1 amp 2 P F A U Axial Compression P where P 0 66 for lt 2 25 LRFD 6 9 4 1 1 uz 0 88F A 2 F 3 F rr E Where K 0 75 for bolted or welded end and 0 875 for pinned ends for gt 2 25 LRFD Eq 6 9 4 1 2 5 10 TABLE 5 1 DEFINITION OF GROUP LOADINGS COMBINATION WSD GROUP DL LL 1 w WL LF T l 1 1 100 1 2 150 1 1 125 II 1 1 0 3 1 1 125 IV 1 1 1 125 V 1 1 1 140 VI 1 1 0 3 1 1 1 140 TABLE 5 1a DEFINITION OF GROUP LOADINGS COMBINATION LRFD GROUP DL LL 1 WS WL Tu Strength 1 25 1 75 0 5 1 2 St
51. es If the vehicle is not one of those predefined in Table 3 2 data types 0304 0305 and 0306 should be input for state vehicles 1 2 and 3 respectively WSD ONLY STATE VEHICLE POSTING ALLOWABLE STRESS FACTOR FOR TRUSS MEMBER Decimal Input the allowable stress factor to be used in the Posting Rating of the specified state vehicles If left blank the system will use the standard AASHTO factor of 0 75 WSD ONLY STATE VEHICLE POSTING ALLOWABLE STRESS FACTOR FOR CABLE Decimal Input the allowable stress factor to be used in the Posting Rating of the specified state vehicles If left blank the system will use the standard AASHTO factor of 0 9 33 SPECIAL VEHICLE DATA Data Type 0302 1 Special Truck Identification and Posting Information SPECIAL VEHICLE LOADING DESIGNATION Alphanumeric Input any code to identify the special truck SPECIAL VEHICLE DESCRIPTION Alphanumeric Input any description of the vehicle to be given in the program output WSD ONLY SPECIAL VEHICLE ALLOWABLE STRESS FACTOR FOR TRUSS MEMBER Decimal Input the allowable stress factor to be used in the Posting Rating of the special vehicle If left blank the system will use the standard AASHTO factor of 0 75 WSD ONLY SPECIAL VEHICLE ALLOWABLE STRESS FACTOR FOR CABLE Decimal Input the allowable stress factor to be used in the Posting Rating of the special vehicle If left blank the system will use the standard AASHTO factor of 0 9 SPECIAL VEHICLE CO
52. ever if left blank the program assumes 0 75 For cable the allowable stress is 0 9 For LFR or LRER allowable stress is replaced by the capacity 6 Special Truck Posting Live loading consists of the special truck as 2 3 designated on input data type 0302 and 0303 The allowable stress can be specified on data type 0302 or the system will assume a value of 0 75 for truss members and 0 9 F for cable For LFR or LRFR allowable stress is replaced by the capacity The TRAP system uses program generated influence lines as the means for calculating member forces Application of the live load with impact results in the actual maximum live load stress for each structural member The Rating Factor see Section 5 5 Rating is computed for each structural member as follows AllowableStress DL Stress Rating Factor 5 Actual LL D Stress Capacity DL Force Rating Factor LL I Force A rating factor less than one indicates that the structural member does not adequately sustain the given live load 27 PRESTRESSING The truss can be prestressed using three different cable layouts The TRAP program can analyze this type of prestressed truss In the case of draped cable the cable changes its direction through the rotation over a pulley placed on the truss joint A more detailed description of the methodology and the equation used in the analysis and rating are given in Chapter 6 Methodology of Pre
53. g Rating a Truss member in tension F OR For min FyAg FuAnU Ag 5 6 b Truss member in compression F F IR e F OR A Foc Where F OR the allowable stress for Operating Rating and F amp IR is calculated by Equation 5 4 or 5 5 depending on KL r value For the allowable tension stress factor for operating rating default 0 75 Foc factor of safety of compression member for operating rating default 1 7 otherwise 2 12 0 75 For 1 7 3 Posting Rating Truck 1 2 3 or a Special Truck 5 8 a Truss member in tension Fa Post min FyAg F A U A 5 8 b Truss member in compression F IR 5 9 PC Where F Post the allowable stress for Posting Rating regardless of whether the loading is Truck1 2 3 or a Special Truck Fpr the allowable tension factor for posting default 0 75 factor of safety of compression member for posting default 1 7 otherwise 2 12 0 75 1 7 After the allowable stress is calculated Equation 5 1 is applied to compute the rating factor which indicates the adequacy of the structure under the applied live load 5 6 Rating LFR or LRFR For Load Factor Rating LFR or Load and Resistance Factor Rating LRFR Equation 5 1 is changed to Capacity DL Force 5 10 where Capacity is given in the AASHTO Manual for Condition Evaluation of Bridges for 5 9 tension and compression m
54. ill be given or group loading is required Input 1 2 3 or 4 as described in Table 3 1 Definition of System Options MODULUS OF ELASTICITY KSI or MPa Real Input the modulus of elasticity If left blank the system will use the modulus of elasticity for steel 29 000 ksi WIND INTENSITY KSF or MPa Real Input the wind intensity to be used in the analysis for group loading If left blank the system will use a value of 0 075 ksf PRESTRESS OPTION NO 0 YES 1 Integer If a prestressed truss needs to be analyzed or rated input one 1 Data Type 0104 General Truss Configuration SPAN LENGTHS SPAN 1 SPAN 6 FT or m Decimal Input the length of each span in feet Overhangs are not allowed Leave blank the input field for any spans not used CURB DISTANCE FT or m or AXLE DISTRIBUTION FACTOR Input the width between curbs the clear roadway width or the LL axle distribution factor If the width between curbs is entered the LL axle 3 1 distribution factor will be automatically calculated according to AASHTO specifications DISTANCE BETWEEN TRUSSES FT or m Enter the distance in feet between the center line of each vertical truss DEAD LOAD DETAIL FACTOR Input the dead load detail factor to account for bolts weldments etc This factor will be used to increase the weight of all truss members If left blank the system will use one 1 Data Type 0105 Design Method and Load Resistance Factors DESIGN METHOD I
55. ints B These are given as follows Data Types 0701 0702 0801 0802 Bracing Panel Point Loads PANEL POINT NUMBER Integer This is the sequence number of the panel point beginning with one 1 The sequence number for upper lower and additional panel points are as given on input card type 0401 3 10 One panel point can refer to at most a lower upper additional A and additional B panel points LOAD KIPS or KN Decimal Input the value of the vertical concentrated load 3 10 MISCELLANEOUS PANEL POINT LOADS Fig 3 8 Dead loads due to any miscellaneous source can be input as concentrated panel point loads for 1 lower panel points 2 upper panel points 3 panel points A and 4 panel points B These are given as follows Data Types 0901 0902 1001 1002 Miscellaneous Panel Point Loads PANEL POINT NUMBER Integer This is the sequence number of the panel point beginning with one 1 The sequence number for upper lower and additional panel points are as given on input data type 0401 One panel point can refer to at most a lower upper additional A and additional B panel points LOAD KIPS or KN Decimal Input the value of the vertical concentrated load Table 3 1 Definition of System Options Data Type 0103 SYSTEM OPTION DESCRIPTION Analysis Only This option indicates that the AASHTO Live Load specified on data type 0301 under Inventory Rating will be applied automatically and the
56. ions of loads which are considered in TRAP In addition to dead load and live load some other loadings regarding the application of combinations of loads are as follows 1 Thermal forces The member forces due to thermal effect are computed automatically by the program from the input temperature change of each member The effect is considered in the specific groups 2 Wind loads on truss For all truss members TRAP automatically determines the member force due to wind loads on the truss using the default intensity 75 Ib sf or user input intensity for different wind conditions 2 2 3 Wind on live load TRAP can determine the member forces due to wind on live load using the default intensity 100 Ib sf 4 Longitudinal forces The effect of longitudinal forces is the partial effect of the live load TRAP determines this automatically 2 6 RATING The rating analysis employed by TRAP utilizes the working stress criteria load factor criteria and load and resistance factor criteria and incorporates the AASHTO specification to limit the stress to a maximum permissible level to which a structural member may be subjected Only axially loaded members are considered in the analysis The allowable axial stress or capacity is determined by the program and is dependent upon whether the structural member is in tension or compression Six possible ratings can be performed by the TRAP system The capability exists whereby the allowable stress le
57. it menu click Delete To cut a row of data so you can move it to another place double click the gray area on the leftmost side of the table to highlight the row Then on the Edit menu click Cut To copy a row of data so you can paste it in another place double click the gray area on the leftmost side of the table to highlight the row Then on the Edit menu click Copy 1 3 To paste a row of data you have cut or copied double click the gray area on the leftmost side of the table to highlight the row where you want to put the data Then on the Edit menu click Paste To undo your last action on the Edit menu click Undo Going to the next or previous screen Clicking on the lt back gt icon takes you back to the previous screen Clicking on the lt down gt icon takes you down to the next screen Going to a specific screen On the Input Screen menu click any input screen title On the Go To menu click any input screen data type number Run Utility is accessed by clicking on the Run in the main menu It allows you to execute the TRAP program using the data stored in any of your input data files To select an input data file 1 Click the Input File button 2 In the Look in box click the drive that contains the file 3 Below the look in box click the folder that you want 4 Double click the data file or type it in the File Name box NOTE The default output file will appear below the output file button after an input
58. m 3 3 span Continuous Deck Truss 7 30 Appendix A Index of Output Tables A 1 11 Table 2 1 Table 3 1 Table 3 2 Table 3 3 Table 5 1 Table 5 1a Table 5 2 Figure 3 1 Figure 3 2 Figure 3 3 Figure 3 4 Figure 3 5 Figure 3 6 Figure 3 7 Figure 3 8 List of Tables Summary of Program Features and Limitations 2 5 Definition of System 3 12 Allowable Live Load Type 3 13 Default State eene 3 14 Definition of Group Loadings Combination WSD 5 11 Definition of Group Loadings Combination LRFD 5 11 Logd Rating Criteria o een dp eeu 5 12 List of Figures Highway Bridge Truss Nomenclature 3 15 Loaded Verticalss ode t edt 3 16 Member Components cassis NOH ee dtt iaa iaa 3 17 Deck 3 17 3 18 Configuration of Truss Example with Various Types of Cable 3 19 Segmented Uniform Loads 3 20 Panel Point Loads a usa aa 3 20 iii Abstract The computer program TRAP Truss Rating and Analysis Program performs an analysis or rating group loading of a simply supported or continuous span truss havi
59. mmary for Upper Chord Members 10 2A PL DL LL I Force Summary for Upper Chord Members 10 3 DL LL I Force Summary for Additional Members 10 3A PL DL LL I Force Summary for Additional Members 10 4 DL LL I Force Summary for Vertical Members 10 4A PL DL LL I Force Summary for Vertical Members 10 5 DL LL I Force Summary for Diagonal Members 10 5A PL DL LL I Force Summary for Diagonal Members 10 6A PL LL I Force Summary for Straight Cables 10 6B PL LL I Force Summary for One Drape Cables 10 6C PL LL I Force Summary for Two Drape Cables gt lt gt lt lt X III gt gt lt gt lt gt PS gt gt gt lt gt lt gt 11 0 LIVE LOAD DL LL I TRUCK 1 11 1 DL LL I Force Summary for Lower Chord Members 11 1A PL DL LL I Force Summary for Lower Chord Members 11 2 DL LL I Force Summary for Upper Chord Members 11 2A PL DL LL I Force Summary for Upper Chord Members 11 3 DL LL I Force Summary for Additional Members 11 3A PL DL LL I Force Summary for Additional Members 11 4 DL LL I Force Summary for Vertical Members 11 4A PL DL LL I Force Summary for Vertical Members 11 5 DL LL I Force Summary for Diagonal Members 11 5A PL DL LL I Force Summary for Diagonal Members 11 6A PL LL I Force Summary for Straight Cables 11 6B PL LL I Force Summary for One Drape Cables 11 6C PL LL I Force Summary for Two Drape
60. ng up to six spans in accordance with AASHTO specifications 17th Edition with up to 2003 interims and AASHTO LRFD Design Specifications Sixth Edition with up to 2013 interims Also the program since version 4 00 is capable of performing the analysis and rating of a prestressed truss Live load using State of Maryland or AASHTO is performed automatically In addition a general truck configuration having up to forty 40 axles may be input for a special posting rating analysis The program uses the direct stiffness method to generate influence lines for truss member forces cable forces reactions and panel point deflections These influence lines then are used to determine the maximum compressive and tensile forces in each member under the indicated live loading Capabilities include the automatic computation of Inventory Operating and Posting Ratings per AASHTO recommendations Output contains a verification of truss geometry and loading input and includes member cable and panel point data truss heights and geometric data for all members Also included in the output are panel point dead loads deflections reactions and a force summary due to DL LL I for all members Finally a summary of the truss rating analysis output is given Output of a group loading analysis and the governing case can be obtained by inputting the appropriate program option A new feature added allows rating using either Load Factor LFD or Load and Resist
61. nteger Working Stress Design 0 Load Factor Design 1 Guide Load and Resistance Factor Design 2 or AASHTO Load and Resistance Factor Design 3 DEAD LOAD FACTOR Decimal Default is 1 0 for WSD 1 3 for LFD and 1 25 for LRFD PRESTRESS LOAD FACTOR Decimal Default is 1 0 LIVE LOAD FACTOR FOR AASHTO TRUCK Decimal Default is 1 0 for WSD and 1 3 x 5 3 for LFD and 1 75 for LRFD LIVE LOAD FACTOR FOR STATE VEHICLE Decimal Default is 1 0 for WSD and 1 3 x 5 3 for LFD and 1 75 for LRFD LIVE LOAD FACTOR FOR OVERLOAD Decimal Special Vehicle is considered an overload Default is 1 0 for WSD and 1 3 x 5 3 for LFD and 1 35 for LRFD IMPACT FACTOR Decimal Default is AASHTO impact factor If specified it will be constant throughout RESISTANCE FACTOR for TENSION Decimal Default is 1 0 a For LFD 1 or LRFD Guide 2 the Resistance Factor is applied to tension allowable as a reduction factor lt 1 0 where P follows the LRFD calculation b For LRFD 3 the Resistance Factor where condition factor system factor and resistance factor is applied to tension to represent a reduction factor to account for shear lag The lesser of P 0D F Ay 0 95DpF Az and P F A 0 8 0 will be used as the tensile resistance AASHTO LRFD Art 6 8 2 2 U 1 for welded connection U 0 90 for flange bolted rolled I and tee shapes with flange widths not less than 2 3 the de
62. nts Examples include L4U5 A1U2 L5U5 etc There are four fields 1 alpha of 1 character 1 numeric of 3 characters 1 alpha of 1 character and 1 numeric of 3 characters The numeric fields should be right justified if less than three digits L Lower U Upper Additional Codes A B B etc RELEASED MEMBER Integer Use 1 if the member is free from resisting axial forces such as in dammy members LOADED MEMBER SEQUENCE NO Integer The sequence of loaded vertical members starting from the left see Figure 3 2 NOTE A loaded member must always be specified at the first and last panel points of a truss bridge This would be the vertical end post for a truss having end verticals For a truss without end verticals the horizontal or near horizontal member framing into each end panel point is specified as the first and last loaded member respectively A diagonal member is never given a loaded member sequence number LOADED MEMBER DECK LOCATION FT or m Decimal The distance from the top of the loaded vertical member to the point where the deck is connected see Figure 3 4 MINIMUM RADIUS OF GYRATION IN or mm Decimal The value of the minimum radius of gyration of the member MEMBER DEPTH IN or mm Decimal The depth of the member measured along an axis parallel to the connecting plates see Figure 3 3 MEMBER AREA GROSS SQ IN or mm H 100 Decimal The gross area of the member MEMBER AREA NET SQ IN or mm H 100
63. o save a new unnamed data file 1 On the File menu click Save As 2 In the File name box type a name for the data file 3 Click Save 1 2 To save an existing data file On the File menu click Save Input Screens The available input categories are Structure Live Load Dead Load and Geometry Each category has its own submenu s which include related bridge input data screens Using the keyboard with input screens To move in a table Press To the next cell in the row ENTER or TAB or Right arrow To the previous cell in the row Left arrow Up one row in a table Up arrow Down one row in a table Down arrow To move in individual fields Press space bar To the next field ENTER or TAB or Right arrow or Down arrow To the previous field Left arrow or Up arrow To delete cut copy and paste data in a field To delete data select them Then on the Edit menu click Delete To cut data so you can move it to another field select the data Then on the Edit menu click Cut To copy data so you can paste a copy of it in another field select the data Then on the Edit menu click Copy To paste data you have cut or copied click the place where you want to put the data Then on the Edit menu click Paste To undo your last action on the Edit menu click Undo To delete cut copy and paste data in a row To delete a row of data double click the gray area on the leftmost side of the table to highlight the row Then on the Ed
64. oint for different cases which are described as follows 1 For a through truss without first upper panel point the X and Y coordinates of the lower panel point should be specified with right justification within the entry block while the other coordinate entries should be left blank e g DATA PANEL LOWER PANEL PT UPPER PANEL PT NO POINT X Y X Y 2 For a deck truss without first lower panel point the X and Y coordinates of the upper panel point should be specified with right justification within the entry block while the other coordinate entries should be left blank e g DATA PANEL LOWER PANEL PT UPPER PANEL PT NO POINT X Y x Y 3 For a through or deck truss with first panel vertical member both upper and lower panel point coordinates should be filled with right justification within the entry block e g DATA PANEL LOWER PANEL PT UPPER PANEL PT NO POINT x Y x Y Other panel points coordinates can be input within the appropriate entry blocks 36 MEMBER DATA Data Type 0501 Member Data Truss member data must be entered left to right in the following order 1 All lower chords 2 All upper chords 3 All additional chords A and B if any 4 All vertical members 5 All diagonal members MEMBER NO Integer The member sequence number starting with 1 and ending with the total number of members MEMBER LOCATION AND DESIGNATION Alphanumeric The designation of each member with respect to the panel poi
65. ons 1 Are you familiar with Microsoft Windows Do you have an understanding of the concepts and use of terms such as menus help screens cursor mouse files etc 3 Have you read installed the TRAP software using the installation instructions you received 4 Have you filed your installation instructions with your other TRAP reference material If you cannot answer Yes to all of these questions please take the time to address them before continuing on in this manual If you are prepared to continue take a moment to look over the Table of Contents provided at the beginning of this manual You will find that the remainder of this document illustrates the detailed use of the four basic utility functions of TRAP in Section 1 4 The remainder of this section describes how to enter TRAP and how to access the Main Menu 1 2 Accessing the Main Menu The TRAP MAIN MENU is the main access screen to each of the utilities provided within the TRAP system It is also the main return point when you have finished using one of the utilities If you have not yet done so please refer to your installation instructions and install your TRAP software If your PC is currently off simply turn it on and run Microsoft Windows After entering Windows TRAP can be run by double clicking the TRAP icon The TRAP 1 1 Introduction Screen will be displayed on your monitor in a few seconds 1 3 The TRAP Main Menu This screen allows you to ac
66. or MPa Decimal The yield stress of the material used as given by the AASHTO specifications PRESTRESS FORCE KIPS or KN Decimal Input the prestress force used in prestressing the cable INFLUENCE LINE OPTION Integer An option which will allow the user to select which member influence line will be output Input 0 or leave blank if no influence line output is desired 2 Input 1 if a table of influence line values for the given member is to be output 38 UNIFORM DEAD LOADS FIG 3 7 Data Type 0601 Dead Load Data Uniform Dead Loads for the truss deck can be given as 1 Uniform loads due to floor steel 2 Uniform loads due to slab and wearing surface 3 Uniform loads due to railing and curb and 4 Uniform loads due to utility and accessories These are input as follows Data Types 0601 0602 0603 0604 Uniform Dead Loads LOAD NO Integer Input sequence load segment beginning with one 1 These are precoded on the input sheets LOAD KLF or KN m Decimal Input the intensity of the load in kips per linear foot of the truss DISTANCE FROM LEFT END BRIDGE FROM TO FT or m Decimal The location of the left and right ends of the uniform loaded segment measured from the left end of the bridge 39 PANEL POINT BRACING DEAD LOADS FIG 3 8 Dead loads due to lateral bracing can be input as concentrated panel point loads for 1 lower panel points 2 upper panel points 3 panel points A and 4 panel po
67. or Strength V for LRFD Group Loading IV for WSD LFD or Strength VI for LRFD Group Loading V for WSD LFD or Service I for LRFD Group Loading VI for WSD LFD or Service II for LRFD SUMMARY OF CRITICAL COMBINATION OF LOADS Critical Loading for Lower Chords Critical Loading for Upper Chords Critical Loading for Additional Members Critical Loading for Vertical Members Critical Loading for Diagonal Members These tables are generated for the Cable Option only A 11
68. program flexibility the dead load is categorized into three types 1 uniform loads along the deck 2 concentrated panel point loads and 3 the weight of the truss Dead loads which are uniform along the deck are used to describe the floor steel slab and wearing surface railing and curb and utilities and accessories These are given in units of kips per linear foot and may be composed of up to 9 segments of differing intensities In determining the effect of deck loads the deck either supported directly at a panel point or attached to a vertical member is assumed to act as a simple beam between support points If the deck is attached to any vertical member it is assumed that the load from the deck reaction is distributed to the upper and lower support points of the vertical member in the proportion shown in Figure 3 4 Dead loads which are given as concentrated panel point loads are used to describe wind bracing dead loads or any miscellaneous loads which may occur These may be placed on any or all of the joints throughout the truss downward taken as positive Dead loads due to the weight of the truss are obtained by accumulating the simple beam reactions due to member weights at each panel point throughout the truss The member weights 5 1 are computed by taking the product of the member lengths the gross member areas and the density of steel taken as kcf times a constant detail factor 53 LIVE LOAD The live load cap
69. pth and n less than 3 fasteners per line U 0 85 for other bolted members with no less than 3 fasteners per line U 0 70 for all bolted members with 2 fasteners per line RESISTANCE FACTOR for COMPRESSION Decimal Default is 1 0 a For LFD 1 the total Resistance Factor is 0 85 b For LRFD Guide 2 the total Resistance Factor is Pr c For 3 the total Resistance Factor is 0 9 where condition factor system factor and LRFD resistance factor DUCTILITY REDUNDANCY and IMPORTANCE FACTOR 7 npnryr LRFD only n and n2 are defined below a For Strength Limit State use only 77 Decimal Default is 1 0 b For other limit states 42 Decimal Default is 1 0 3 2 Live Load and Rating Data Data Type 0301 General Live Load and Rating Data AASHTO LIVE LOAD INVENTORY OPERATING LOAD NAME Alphanumeric Input the standard AASHTO L H or HS Truck Designation or HL 93 LRFD design vehicular live load See Table 3 2 for standard truck designations If SYSTEM OPTION 1 for Analysis Only see Table 3 1 then this vehicle will be the only live load considered in the truss analysis All other columns of this data type should then be left blank If SYSTEM OPTION 2 for Rating Only see Table 3 1 then this vehicle will be the live load used to compute the bridge Inventory Rating Other rating vehicles may be input as described below WSD ONLY AASHTO
70. put 2 9 Influence line option 2 10 Combination of loads 2 11 Complete analysis of prestressed cable truss system 3 0 INPUT All numerical input must have a decimal point except those designated as integer or alphanumeric which must be right justified All data types except project description cards require a header card with only the data type number given and the remaining fields blank By using the Windows version field justification and header cards will be taken care of by the program 3 1 SYSTEM DATA Data Type 0101 Project Description Alphanumeric Input a general description of the project program that is to be printed on the first page of the output only This may consist of up to two input lines Data Type 0102 Project Description Alphanumeric Input a single line description of the project or problem that is to be printed on every page of output Data Type 0103 Program Options OUTPUT LEVEL Integer This value allows the selection of various analysis rating tables to be output Input 1 if primary basic output is desired Use 2 if additional detail beyond that given by the basic output level is required Input 3 and influence values for reactions are given with level 2 Member force influence line values are given with additional input as described in Section 3 6 Member Data SYSTEM OPTION Integer This input data indicates that the truss is to be analyzed rated and that only input verification w
71. rength Il 1 25 1 35 0 5 1 2 Strength 1 25 1 4 0 5 1 2 Strength IV 1 25 0 5 1 2 Strength V 1 25 1 35 0 4 0 4 0 5 1 2 Service I 1 0 1 0 0 3 0 3 1 0 1 2 Service 1 0 1 0 1 2 Where DL Dead Load LL I Live Load Plus Impact WS Wind Load On Truss WL Wind Load On Live Load LF Longitudinal Forces T Thermal Forces 96 Percentage Of Basic Unit Stress TABLE 5 2 LOAD RATING CRITERIA ITEM LRFD RATING LFD RATING LOADS TO BE RATED HL 93 HS 20 or Standard lane Loading Type 3 Type 352 Type 3 3 RESISTANCE FACTOR As Determined from AASHTO LRED Bridge As Determined from AASHTO Design Specifications Article 6 5 4 2 Design Specifications DEAD LOAD FACTOR 1 25 1 3 LIVE LOAD FACTOR As Determined from the Manual for Bridge As Determined from AASHTO Evaluation Table 6A 4 2 2 1 Maintenance Manual Inventory Rating 2 17 Ranges 1 30 to 1 75 Operating Rating 1 30 IMPACT As Determined from the manual for Bridge As Determined from AASHTO Evaluation Article 6A 4 4 3 Design Specification Formula 3 1 MULTIPLE LANE LIVE As Determined from AASHTO LRFD Bridge As Determined from AASHTO LOAD REDUCTION Design Specifications Table 3 6 1 1 2 1 Maintenance Manual FACTORS 1 Lane 1 2 1 2 Lanes 1 00 2 Lane 1 00 3 Lanes 0 85 4 or More Lanes 0 65 E Lanes Determined by Bridge Striping 3 Lanes 0 90 4 More Lanes 0 75 Lanes Determined by Bridge Curb to Curb Width 5 12 60 METHODOLOGY OF PR
72. ria are given in Table 5 1 The percentage of the basic unit stress for the various groups is also given in Table 5 1 Approaches for the Wind Load In the TRAP system only the plane truss analysis is used Under real circumstances the direction of wind load is perpendicular to the whole plane truss The following are the approaches and assumptions made when the wind loads are converted into the plane forces A Wind Load on Truss W a Calculate the wind load on each member Force Area Intensity Area of each member member length member depth 5 4 Intensity 75 Ib sf 3591 Pa or input value b The force from step a can be taken by two joints of each member equally Repeat steps a and b to calculate the wind force for all members After step c all wind forces are exerted on the joint If the total force of all joints from steps a to d is less than 450 Ib ft 6 57 KN m use 450 Ib ft 6 57 KN m instead by adjusting proportionally Article 3 15 1 of AASHTO 2002 f If the support is on the lower panel point take the moment about the lower panel point The moment produces a vertical downward force at that panel point on the windward plane truss The vertical force acts on the lower panel point On the other hand if the support is on the upper panel point take the moment about the upper panel point and the vertical force acts on the upper panel point The vertical force the moment truss width
73. s the maximum permissible truck load allowed for a given truss bridge configuration based on an allowable stress level higher than the allowable design stress Usually this allowable stress is 0 75 Fy SAFE LOAD CAPACITY RATING POSTING determines whether any specific vehicle may pass safely over the bridge Such vehicles are normally heavier than those vehicles for which an Operating Rating is computed Special permits are issued to these trucks if the axle load distribution is such that the stresses produced do not exceed the allowable stress level for an Operating Rating This again is usually taken as 0 75 Fy The TRAP system will apply the standard AASHTO live load vehicles automatically to determine a truss bridge s inventory and operating rating Additionally a measure of standard state trucks specified by the user can be built into the system such that they can be used for a posting rating by merely specifying the vehicle name in the input Finally a general truck of any configuration may be input and a posting rating determined See Section 3 0 Input In the WSD rating analysis procedure a Rating Factor for the truss system is formed by the following formula Rating Factor AllowableStress DL Stress Actual LL I Stress 5 1 This factor dictates the capacity of the bridge to withstand the designated live load A 5 6 rating factor greater than unity indicates that the particular live load considered
74. s treated as a separate member like any other truss member The cable force is constant along the cable member regardless of whether the cable is straight or draped A cable layout should not coincide with one truss member Cable ends should be anchored to truss joints and in the case of draped cable where a pulley is used the pulley should be attached to a truss joint For more details refer to Figure 3 6 The analysis of prestressed cable trusses is divided into two stages In the first stage an analysis is performed using the dead load and prestressing load is applied to the truss without considering the cable stiffness The second analysis stage considers the live load and the stiffness matrices of the cables The final solution is achieved by imposing the solutions of the two stages 6 1 A closed form solution for the relationship between the cross sectional area the prestressing force of the cable and the desired final member stress after prestressing is derived for a statically determinate truss The final truss member stress fm is given by 6 1 where is truss member force due to dead load Am 15 the member area is the applied prestress stress in the cable Ac is the cable area and is the truss member force due to live load The final cable stress is Ti ut where f is the allowable cable stress Equation 6 2 can be rewritten as T EUM WT 6 3 Substituting Equation
75. stressed Cables TABLE 2 1 SUMMARY OF PROGRAM FEATURES AND LIMITATIONS NO ITEM AND DESCRIPTION 1 0 LIMITATIONS Limit 1 1 Maximum number of spans 6 1 2 Maximum number of joints 400 1 3 Maximum number of members and cables 450 1 4 Maximum number of detail factors 1 5 Maximum number of joints at any panel point 1 6 Maximum number of uniform DL segments 1 7 Maximum number of supports 1 8 Maximum number of panels 100 1 9 Maximum number of straight cables 10 1 10 Maximum number of one drape cables 10 1 11 Maximum number of two drape cables 10 1 12 Members are assumed to act in both tension and compression Cables are assumed to act in tension only 1 1 Overhangs are not allowed 2 0 FEATURES 2 1 Conforms to the 2003 AASHTO Standard Specifications and AASHTO LRFD Specifications 6 Edition with 2013 Interim 22 Automated DL for all construction conditions including ties 23 Automated LL for AASHTO Interstate AREA and special trucks 24 All impact factors are automatically calculated either on the basis of the actual span length or loaded lengths where appropriate 2 5 y 4 Bridge be determinate indeterminate of configuration e g deck truss through truss etc 2 6 Maximum positive and negative effects are given for ll members and cables reactions and deformations 27 User specified truck loadings 2 8 User can specify different levels of out
76. tioning the specified trucks over the maximum ordinates of the influence lines In the WSD LFD analysis case where an HS loading is specified H trucks also are tested automatically 4 Impact Factors For LRFD Impact factor is a constant For WSD or LFD impact factors are calculated by using the formula TES L 125 in which I is the impact fraction maximum 30 minimum 10 and L is a length 5 3 a b given as follows For a member force L is taken as the loaded length of the influence line If 2 spans contribute to the maximum member force the L is taken as the average of 2 loaded lengths However in order for the second loaded length to be considered in the determination of L it must have an area of 60 or more of the maximum area over the primary loaded length If it does not contribute in at least this amount it is discounted as being a loaded length For end support reactions and lower panel point deflections L is taken as the span length For intermediate support points L is taken as the average of the adjacent span lengths 54 LOAD COMBINATIONS The load combination capability of this program includes automatic determination of seven different groups and the critical group for each member The specific assumptions and methodology are as follows 1 2 Definitions of the Specific Groups There are 7 groups considered in this program Group loading combinations for working stress crite
77. ue of six 6 predefined state vehicles are given in Table 3 3 SPECIAL VEHICLE LOADING DATA TYPES 0302 AND 0303 Any 9 Character Alphanumeric 3 13 Up to 40 axles Table 3 3 Default State Vehicle VEHICLE DESCRIPTION Axle 1 2 3 5 6 7 8 9 10 32 8 2D sist spacing 4 12 L I eee E MR spacngern 16 4 2 a Weight 16 17 17 P TYPE 3 is ere ETE ER NN ERE n 4 2 8 me see e De e D D D L sp 15 4 15 la a 10 4 m 4 mao aaa OL2 EISE DIES Weight K 15 74 26 98 26 98 26 98 26 98 26 98 26 P82 ER LE EORR Cooper E80 3 14 Maximum 4 Joints Any PP Us Us Y MEMBER RELEASE 1 07 ADDITICNAL CHORDS As A 7 HORIZ 5 AND ROAD GRADE SPAN 1 SPAN 2 SPAN 3 FIG 3 1 HIGHWAY BRIDGE TRUSS NOMENCLATURE 3 15 FIG 3 2 LOADED VERTICALS GRADE LINE DIST FROM LOADED MEM TO DECK NOTE CIRCLED NUMBER INDICATES LOALZD MEMSER SEQUENCE 3 16 GUSSET PLATE GUSSET PLATE AREA IN GUSSET PLATE CONSIDERED A PART OF SPLICE PLATE DEPTH OF MEMBER FIG 3 3 MEMBER COMPONENTS FIG 3 4 DECK LOAD
78. vel for a particular rating function can be input to override the system default value These six rating types and the allowable stress which is used automatically for each are given as follows 1 Inventory Rating Live loading consists of the AASHTO truck H HS or Interstate or lane loading Unless otherwise specified the allowable stress is 0 55 Fy For cable the allowable stress is 0 6 Fy For LFR or LRFR allowable stress is replaced by the capacity 2 Operating Rating Live loading consists of AASHTO truck H HS or Interstate or lane loading Unless otherwise specified the allowable stress is 0 75 Fy For cable the allowable stress is 0 9 Fy For LFR or LRFR allowable stress is replaced by the capacity 3 Posting 1 Live loading consists of the State Truck 1 as designated on input data type 0301 The allowable stress is normally input however if left blank the program assumes 0 75 Fy For cable the allowable stress is 0 9 For LFR or LRFR allowable stress is replaced by the capacity 4 Posting 2 Live loading consists of the State Truck 2 as designated on input data type 0301 The allowable stress is normally input however if left blank the program assumes 0 75 For cable the allowable stress is 0 9 Fy For LFR or LRFR allowable stress is replaced by the capacity 5 Posting 3 Live loading consists of the State Truck 3 as designated on data type 0301 The allowable stress is normally input how

TRAP - Bridge Engineering Software & Technology (BEST) Center

Contents

Download Pdf Manuals

Related Search

Related Contents

TRAP - Bridge Engineering Software &amp; Technology (BEST) Center

Contents

Download Pdf Manuals

Related Search

Related Contents

TRAP - Bridge Engineering Software & Technology (BEST) Center