Volume I: Evaluation of Existing Roadside Safety Hardware Using Updated Criteria—Technical Report (2010)

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Web-Only Document 157: Volume I: Evaluation of Existing Roadside Safety Hardware Using Updated Criteria—Technical Report National Cooperative Highway Research Program D. Lance Bullard, Jr. Roger P. Bligh Wanda L. Menges Rebecca R. Haug Texas Transportation Institute College Station, TX Contractor’s Final Report for NCHRP Project 22-14(03) Submitted March 2010 NCHRP

ACKNOWLEDGMENT This work was sponsored by the American Association of State Highway and Transportation Officials (AASHTO), in cooperation with the Federal Highway Administration, and was conducted in the National Cooperative Highway Research Program (NCHRP), which is administered by the Transportation Research Board (TRB) of the National Academies. COPYRIGHT INFORMATION Authors herein are responsible for the authenticity of their materials and for obtaining written permissions from publishers or persons who own the copyright to any previously published or copyrighted material used herein. Cooperative Research Programs (CRP) grants permission to reproduce material in this publication for classroom and not-for-profit purposes. Permission is given with the understanding that none of the material will be used to imply TRB, AASHTO, FAA, FHWA, FMCSA, FTA, Transit Development Corporation, or AOC endorsement of a particular product, method, or practice. It is expected that those reproducing the material in this document for educational and not-for-profit uses will give appropriate acknowledgment of the source of any reprinted or reproduced material. For other uses of the material, request permission from CRP. DISCLAIMER The opinions and conclusions expressed or implied in this report are those of the researchers who performed the research. They are not necessarily those of the Transportation Research Board, the National Research Council, or the program sponsors. The information contained in this document was taken directly from the submission of the author(s). This material has not been edited by TRB.

TABLE OF CONTENTS Section Page LIST OF FIGURES ..................................................................................................................... viii LIST OF TABLES ......................................................................................................................... xi I. INTRODUCTION .......................................................................................................................1 RESEARCH PROBLEM STATEMENT ............................................................................1 RESEARCH OBJECTIVE ..................................................................................................1 II. STATE OF THE PRACTICE ....................................................................................................3 III. ASSESSMENT OF ROADSIDE SAFETY HARDWARE ...................................................12 GENERAL PERFORMANCE CONSIDERATIONS .......................................................12 Structural Adequacy .......................................................................................................14 Vehicle Stability .............................................................................................................17 Occupant Compartment Deformation .............................................................................18 GUARDRAILS ..................................................................................................................20 Strong-Post W-Beam Guardrail [modified G4(1S) and G4(2W)] ..................................21 Thrie-Beam Guardrail (G9) ............................................................................................22 Thrie-Beam Guardrail (steel posts and routed wood blockouts) ....................................23 Thrie-Beam Guardrail on Strong Wood Posts ................................................................23 Modified Thrie-Beam Guardrail .....................................................................................24 Weak-Post W-Beam Guardrail (G2) ...............................................................................25 Low-Tension Cable Guardrail (G1) ................................................................................26 Weak-Post Box-Beam Guardrail (G3) ............................................................................27 AESTHETIC BARRIERS .................................................................................................28 Test Level 3 ....................................................................................................................29 Rough Stone Masonry Guardwall ................................................................................29 Type A Steel-Backed Timber Guardrail ......................................................................29 Merritt Parkway Steel-Backed Timber Guardrail ........................................................30 Test Level 2 ....................................................................................................................32 Type B Steel-Backed Timber Guardrail ......................................................................32 Round Steel-Backed Timber Guardrail .......................................................................32 Deception Pass State Park Log Rail .............................................................................33 Test Level 1 ....................................................................................................................35 Glacier Park Removable Timber Guardrail .................................................................35 Glacier Park Round Removable Timber Guardrail .....................................................36 MEDIAN BARRIERS .......................................................................................................37 Cable Median Barrier......................................................................................................38 Concrete Median Barrier ................................................................................................39 Portable and Precast Concrete Median Barrier ...............................................................44 Low-Profile Barrier – Test Level 2 .................................................................................44

TABLE OF CONTENTS (CONTINUED) Section Page Portable and Precast Median Barrier Connections .........................................................46 F-Shape Type X Connection ........................................................................................49 Portable and Precast Median Barrier Connections Summary ......................................51 TRANSITIONS .................................................................................................................51 TL-3 Transition ...............................................................................................................52 TL-2 Transition ...............................................................................................................59 General Transition Discussion ........................................................................................60 END TERMINALS AND CRASH CUSHIONS ..............................................................61 End Terminals .................................................................................................................62 Test Level 3 Guardrail Terminals ................................................................................62 Test Level 2 Guardrail Terminals ................................................................................66 Crash Cushions ...............................................................................................................69 Connecticut Impact Attenuator System .......................................................................69 Narrow Connecticut Impact Attenuator System ..........................................................71 Thrie-Beam Bullnose Guardrail System (Bullnose Attenuator) ..................................72 BREAKAWAY HARDWARE - SIGN SUPPORTS AND LUMINAIRES .....................74 Wedge Anchor Sign Support ..........................................................................................80 Summary of Wedge Anchor Results ............................................................................83 Discussion of Test 2 of Wedge Anchor System ..........................................................83 Texas Triangular Slip Base .............................................................................................85 Summary of Texas Slip Base Test Results ..................................................................88 Discussion of Texas Slip Base System ........................................................................88 CONCLUSIONS................................................................................................................88 IV. CRASH TESTING MATRIX AND EVALUATION PLAN ................................................89 SMALL SIGN SUPPORTS AND LUMINAIRE BASES ................................................95 THRIE-BEAM LONGITUDINAL BARRIER .................................................................96 W-BEAM TRANSITIONS TO SAFETY AND F-SHAPE BARRIER ............................96 BURIED-IN-BACKSLOPE TERMINAL .........................................................................96 CABLE GUARDRAIL ......................................................................................................96 OTHER GUARDRAILS ...................................................................................................97 SUMMARY .......................................................................................................................97 V. FULL-SCALE CRASH TESTING ..........................................................................................99 32-INCH NEW JERSEY SHAPE BARRIER – SGM11a .................................................99 Test Installation Description ...........................................................................................99 Test Number 476460-1b (MASH Test 4-12).................................................................100 Test Description .........................................................................................................100 Summary of Test Results ...........................................................................................103 Test Number 476460-1-4 (MASH Test 4-11) ..............................................................106 Test Description .........................................................................................................106

TABLE OF CONTENTS (CONTINUED) Section Page Summary of Test Results ...........................................................................................108 W-BEAM GUARDRAIL – G4(2W) ...............................................................................111 Test Installation Description .........................................................................................111 Test Number 476460-1-5 (MASH Test 3-11) ...............................................................112 Test Description .........................................................................................................112 Summary of Test Results ...........................................................................................114 W-BEAM GUARDRAIL – G4(1S) MEDIAN BARRIER .............................................118 Test Installation Description .........................................................................................118 Test Number 476460-1-10 (MASH Test 3-10) .............................................................120 Test Description .........................................................................................................120 Summary of Test Results ...........................................................................................122 Test Number 476460-1-9 (MASH Test 3-11) ...............................................................125 Test Description .........................................................................................................125 Summary of Test Results ...........................................................................................127 PENNDOT W-BEAM TRANSITION ............................................................................130 Test Installation Description .........................................................................................130 Test Number 476460-1-3 (MASH TEST 3-21).............................................................133 Test Description .........................................................................................................133 Summary of Test Results ...........................................................................................135 SMALL SIGN SUPPORTS .............................................................................................138 Test Installation Description .........................................................................................138 Steel U-Channel Support ...........................................................................................138 Perforated Square Steel Tube Support .......................................................................139 Soil Conditions...........................................................................................................139 Test Number 476460-1-2 (Mash Test 3-62) .................................................................141 Test Description .........................................................................................................141 Summary of Test Results ...........................................................................................148 G3 WEAK POST BOX-BEAM GUARDRAIL ..............................................................151 Test Installation.............................................................................................................151 Test Number 476460-1-6 (MASH Test 3-11) ...............................................................152 Test Description .........................................................................................................152 Summary of Test Results ...........................................................................................155 MODIFIED G2 WEAK POST W-BEAM GUARDRAIL ..............................................158 Test Installation Description .........................................................................................158 Test Number 476460-1-7 (MASH Test 3-11) ...............................................................160 Test Description .........................................................................................................160 Summary of Test Results ...........................................................................................162 G9 THRIE BEAM GUARDRAIL ...................................................................................165 Test Installation Desciption ..........................................................................................165 Test Number 476460-1-8 (MASH Test 3-11) ...............................................................166 Test Description .........................................................................................................166

TABLE OF CONTENTS (CONTINUED) Section Page Summary of Test Results ...........................................................................................169 VI. SUMMARY AND CONCLUSIONS ...................................................................................173 PHASE I...........................................................................................................................173 PHASE II – FULL-SCALE CRASH TESTING .............................................................175 New Jersey Safety Shape Barrier ..................................................................................175 Test 4-12 ....................................................................................................................175 Test 3-11 ....................................................................................................................176 G4(2W) W-Beam Guardrail .........................................................................................176 G4(1S) W-Beam Median Barrier ..................................................................................177 Test-3-10 ....................................................................................................................177 Test-3-11 ....................................................................................................................177 W-Beam Transition.......................................................................................................178 Sign Supports ................................................................................................................178 G3 Weak Post Box-Beam Guardrail .............................................................................180 Modified G2 Weak Post W-Beam Guardrail ................................................................180 G9 Thrie Beam Guardrail .............................................................................................181 CONCLUSIONS..............................................................................................................181 VII. REFERENCES ....................................................................................................................185

LIST OF FIGURES Figure Page Figure 1. Yield Line Failure Analysis for Concrete Parapet(9). ................................................ 14 Figure 2. Typical Cross-Section of Strong-Post W-Beam Guardrail. ...................................... 21 Figure 3. Typical Cross-Section of Thrie-Beam Guardrail. ..................................................... 23 Figure 4. Typical Cross-Section of Modified Thrie-Beam Guardrail System. ......................... 24 Figure 5. Typical Cross-Section of Weak Post W-Beam Guardrail System. ........................... 25 Figure 6. Typical Cross-Section of Low-Tension Cable Guardrail System. ............................ 26 Figure 7. Typical Cross-Section of Weak-Post Box-Beam Guardrail System. ........................ 28 Figure 8. Rough Stone Masonry Guardwall System. ............................................................... 29 Figure 9. Type A Steel-Backed Timber Guardrail System. ...................................................... 30 Figure 10. Merritt Parkway Steel-Backed Timber Guardrail System. ....................................... 31 Figure 11. Type B Steel-Backed Timber Guardrail System. ...................................................... 32 Figure 12. Round Steel-Backed Timber Guardrail System. ....................................................... 33 Figure 13. Deception Pass State Park Log Rail System. ............................................................ 34 Figure 14. Glacier Park Removable Timber Guardrail System. ................................................. 35 Figure 15. Glacier Park Round Removable Timber Guardrail System. ..................................... 36 Figure 16. Typical Cross-Section of a Low-Tension Cable Median Barrier System. ................ 39 Figure 17. Typical Cross-Section of New Jersey Shape Concrete Safety Barrier. ..................... 40 Figure 18. Typical Cross-Section of F-Shape Concrete Safety Barrier. ..................................... 41 Figure 19. Typical Cross-Section of Single Slope Concrete Barrier. ......................................... 41 Figure 20. Typical Cross-Section of Low-Profile Barrier Segment. .......................................... 45 Figure 21. F-Shape Concrete Safety Barrier with X-Bolt Connection. ...................................... 50 Figure 22. Elevation of Texas TL-3 Guardrail-to-Concrete Bridge Rail Transition. ................. 59 Figure 23. Texas TL-2 Guardrail-to-Concrete Bridge Rail Transition. ...................................... 60 Figure 24. Buried-in-Backslope Guardrail Terminal. ................................................................. 62 Figure 25. Eccentric Loader Terminal. ....................................................................................... 64 Figure 26. New York Cable Guardrail Terminal. ....................................................................... 65 Figure 27. Vermont Low-Speed Guardrail Terminal. ................................................................ 66 Figure 28. Modified Eccentric Loader Terminal. ....................................................................... 68 Figure 29. Connecticut Impact Attenuator System. .................................................................... 69 Figure 30. Narrow Connecticut Impact Attenuator System. ...................................................... 71 Figure 31. Bullnose Attenuator. .................................................................................................. 73 Figure 32. Sign Support and Luminaire Bases. .......................................................................... 78 Figure 33. Photographs of Wedge Anchor Sign Support. .......................................................... 81 Figure 34. Details of Wedge Anchor Sign Support. ................................................................... 82 Figure 35. Vehicle/Installation Geometrics for Wedge Anchor & Triangular Slip Base Test. ..................................................................................... 84 Figure 36. Photographs of Texas Triangular Slip Base. ............................................................. 86 Figure 37. Details of the Texas Triangular Slip Base. ................................................................ 87 Figure 38. Cross Section of the 32-inch New Jersey Shape Barrier. .......................................... 99 Figure 39. 32-inch New Jersey Shape Barrier Prior to Testing. ............................................... 100 Figure 40. 32-inch New Jersey Shape Barrier after MASH Test 4-12. ..................................... 101

LIST OF FIGURES Figure Page Figure 41. Test Vehicle after MASH test 4-12 on the 32-inch New Jersey Safety Shape Barrier. ................................................... 102 Figure 42. Summary of Results for MASH Test 4-12 on the 32-inch New Jersey Shape Barrier. .............................................................. 104 Figure 43. 32-inch New Jersey Shape Barrier after MASH Test 3-11. ..................................... 107 Figure 44. Test vehicle after MASH Test 3-11 on the 32-inch New Jersey Shape Barrier. .............................................................. 107 Figure 45. Summary of Results for MASH Test 3-11 on the 32-inch New Jersey Shape Barrier. .............................................................. 109 Figure 46. Cross-Section of the G4(2W) W-Beam Guardrail. ................................................. 111 Figure 47. G4(2W) W-Beam Guardrail Prior to Testing. ......................................................... 112 Figure 48. G4(2W) W-Beam Guardrail after MASH Test 3-11. ............................................... 113 Figure 49. Test Vehicle and G4(2W) W-Beam Guardrail after MASH Test 3-11. ................... 114 Figure 50. Summary of Results for MASH Test 3-11 on the G4(2W) W-Beam Guardrail. ..... 116 Figure 51. Cross Section of the G4(1S) W-Beam Median Barrier. .......................................... 119 Figure 52. G4(1S) W-Beam Median Barrier Prior to Testing. ................................................. 119 Figure 53. G4(1S) W-Beam Median Barrier after MASH Test 3-10. ....................................... 121 Figure 54. Test Vehicle after MASH Test 3-10 on the G4(1S) W-Beam Median Barrier. ....... 121 Figure 55. Summary of Results for MASH Test 3-10 on the G4(1S) W-Beam Median Barrier. ................................................................ 123 Figure 56. G4(1S) W-Beam Median Barrier after MASH Test 3-11. ....................................... 126 Figure 57. Test Vehicle after MASH Test 3-11 on the G4(1S) W-Beam Median Barrier. ....... 126 Figure 58. Summary of Results for MASH Test 3-11 on the G4(1S) W-Beam Median Barrier. ................................................................ 128 Figure 59. Details of the Pennsylvania W-Beam Transition. ................................................... 132 Figure 60. W-Beam Transition prior to Testing. ...................................................................... 132 Figure 61. PennDOT W-Beam Transition after MASH Test 3-21. ........................................... 134 Figure 62. Test Vehicle after MASH Test 3-21 on the PennDOT W-Beam Transition. .......... 134 Figure 63. Summary of rResults for MASH Test 3-21 on the PennDOT W-Beam Transition. .................................................................... 136 Figure 66. Details of the Perforated Square Steel Tubing Sign Support. ................................. 140 Figure 67. Perforated Square Steel Tubing Sign Support prior to Testing. .............................. 140 Figure 68. U-Channel Installation after MASH Test 3-62. ....................................................... 142 Figure 69. PSST Sign Support after MASH Test 3-62. ............................................................. 144 Figure 70. Vehicle after MASH Test 3-62 with Small Sign Supports. ..................................... 145 Figure 71. Summary of Results for MASH Test 3-62 on U-Channel Small Sign Support. ...... 146 Figure 72. Summary of Results for MASH Test 3-62 on PSST Small Sign Support. .............. 147 Figure 72. Cross-section of the G3 Weak Post Box-Beam guardrail. ...................................... 151 Figure 74. G3 Weak Post Box-Beam Guardrail after MASH Test 3-11. .................................. 154 Figure 75. Test vehicle after MASH test 3-11 on the G3 weak post box-beam guardrail. ....... 155

LIST OF FIGURES Figure Page Figure 76. Summary of results for MASH test 3-11 on the G3 Weak Post Box-Beam guardrail. ............................................................ 156 Figure 77. Cross-Section of the Modified G2 Weak Post W-Beam Guardrail. ........................ 159 Figure 78. Modified G2 Weak Post W-Beam Guardrail prior to Testing. ............................... 159 Figure 79. G2 Weak Post W-Beam Guardrail after MASH Test 3-11. ..................................... 161 Figure 80. Test Vehicle after MASH Test 3-11 on the G2 Weak Post W-Beam Guardrail. ..... 162 Figure 81. Summary of Results for MASH Test 3-11 on the Modified G2 Weak Post W-Beam Guardrail. .............................................. 163 Figure 84. G9 Thrie Beam Guardrail after MASH Test 3-11. ................................................... 168 Figure 85. Test Vehicle after MASH Test 3-11 on the G9 Thire Beam Guardrail. .................. 168 Figure 86. Summary of Results for MASH Test 3-11 on the G9 Thrie Beam Guardrail. ......... 170

LIST OF TABLES Table No. Page Table 1. Weighted Prioritization by Hardware Category. .......................................................... 5 Table 2. Aggregate Ranking of Roadside Safety Hardware by Frequency of Use. .................... 9 Table 3. Summary of Crash Tests Conducted under NCHRP Project 22-14(02). .................... 13 Table 4. Comparison of Critical Test Vehicle Dimensions. ..................................................... 18 Table 5. FHWA Accepted Temporary Concrete Median Barriers with Pin Connection ......... 47 Table 6. FHWA Accepted Temporary Concrete Median Barriers with Miscellaneous Connections ................................................................................ 48 Table 7. Summary of NCHRP Report 350 Transition Tests ..................................................... 53 Table 8. Summary of FHWA-Accepted Breakaway Hardware. ............................................... 77 Table 9. Compiled Prioritization, Ranking, and Probability for Successfully Complying with MASH Criteria. ...................................................... 90 Table 10. Performance Evaluation Summary for MASH Test 4-12 on the 32-inch New Jersey Shape Barrier. ................................................................ 105 Table 11. Performance Evaluation Summary for MASH Test 4-11 on the 32-inch New Jersey Shape Barrier. ................................................................ 110 Table 12. Performance Evaluation Summary for MASH Test 3-11 on the G4(2W) W-Beam Guardrail. .......................................................................... 117 Table 13. Performance Evaluation Summary for MASH Test 3-10 on the G4(1S) W-Beam Median Barrier. .................................................................. 124 Table 14. Performance Evaluation Summary for MASH Test 3-11 on the G4(1S) W-Beam Median Barrier. .................................................................. 129 Table 15. Performance Evaluation Summary for MASH Test 3-21 on the PennDOT W-Beam Transition. ...................................................................... 137 Table 16. Performance Evaluation Summary for MASH Test 3-62 on the 4 lb/ft U-Channel Small Sign Support. .......................................................... 149 Table 17. Performance Evaluation Summary for MASH Test 3-62 on the PSST Small Sign Support. ............................................................................. 150 Table 18. Performance Evaluation Summary for MASH Test 3-11 on the G2 Weak Post Box-Beam Guardrail. ............................................................. 157 Table 19. Performance Evaluation Summary for MASH Test 3-11 on the G2 Weak Post W-Beam Guardrail. ................................................................ 164 Table 20. Performance Evaluation Summary for MASH Test 3-11 on the G9 Thrie Beam Guardrail. ............................................................................. 171 Table 21. Crash Tests Performed Under NCHRP Project 22-14 That Meet MASH (Passed). ...................................................................................... 181 Table 22. Crash Tests Performed Under NCHRP Project 22-14 That Did Not Meet MASH (Failed). ......................................................................... 183