Evaluation of Existing Roadside Safety Hardware Using Manual for Assessing Safety Hardware (MASH) Criteria (2010)

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Research Results Digest 349 August 2010 RESEARCH PROBLEM STATEMENT National Cooperative Highway Re- search Program (NCHRP) Report 350: Recommended Procedures for the Safety Performance Evaluation of Highway Fea- tures contains guidelines for evaluating the safety performance of roadside fea- tures, such as longitudinal barriers, termi- nals, crash cushions, and breakaway struc- tures. This document was published in 1993 and was formally adopted as the national standard by the Federal Highway Adminis- tration (FHWA) later that year with an im- plementation date for late 1998. In 1998, the American Association of State Highway and Transportation Officials (AASHTO) and FHWA agreed that most types of safety features installed along the National High- way System (NHS) must meet NCHRP Report 350 safety-performance evalua- tion criteria. An update to NCHRP Report 350 was developed under NCHRP Project 22-14 (02), “Improved Procedures for Safety- Performance Evaluation of Roadside Fea- tures.” This document, Manual for Assess- ing Safety Hardware (MASH), published by AASHTO in 2009, contains revised criteria for safety-performance evaluation of virtu- ally all roadside safety features. For exam- ple, MASH recommends testing with heav- ier light truck vehicles to better represent the current fleet of vehicles in the pickup/van/ sport-utility vehicle class. Further, MASH increases the impact angle for most small car crash tests to the same angle as the light truck test conditions. These changes place greater safety-performance demands on many of the current roadside safety features. RESEARCH OBJECTIVE The objective of this project was to eval- uate the safety performance of widely used non-proprietary roadside safety features by using MASH. Features recommended for evaluation included longitudinal barriers (excluding bridge railings), terminals and crash cushions, transitions, and breakaway supports. Evaluation methods included, but were not limited to, engineering assessment, simulation, full-scale crash testing, pendu- lum testing, and component testing. Where practical, cost-effective modifications to sys- tems that do not meet the new criteria were recommended for future evaluation. PHASE I RESEARCH—STATE-OF- THE-ART ASSESSMENT Since its publication in 1993, NCHRP Report 350: Recommended Procedures for the Safety Performance Evaluation of Highway Features established guidance EVALUATION OF EXISTING ROADSIDE SAFETY HARDWARE USING MANUAL FOR ASSESSING SAFETY HARDWARE (MASH) CRITERIA This digest presents the results of NCHRP Project 22-14(03), “Evaluation of Existing Roadside Safety Hardware Using Updated Criteria.” The project was conducted by the Texas Transportation Institute with Principal Investigator D. Lance Bullard, Jr., Roger P. Bligh, Wanda L. Menges, and Rebecca R. Haug. Responsible Senior Program Officer: Charles W. Neissner NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM

for evaluating the safety performance of roadside features, such as longitudinal barriers, terminals, crash cushions, and breakaway structures. This doc- ument was formally adopted as the national standard by FHWA later that year with an implementation date of late 1998. An update to NCHRP Report 350, now known as the Manual for Assessing Safety Hardware (MASH), was developed under NCHRP Project 22-14(02), “Improved Procedures for Safety-Performance Eval- uation of Roadside Features.” This document con- tains revised criteria for safety-performance evalua- tion of virtually all roadside safety features. Changes to the design test vehicles and impact conditions will place greater impact performance demands on many current roadside safety features. It may be of interest to note that as the develop- ment of MASH progressed, it appeared that the new design test vehicle for structural adequacy tests would be a 5000-lb, 3⁄4-ton, standard cab pickup. The rationale was to keep the same body style pickup used under NCHRP Report 350 with a test inertia weight adjusted to reflect the upsizing trend indi- cated in sales of new passenger vehicles. Previous research had concluded that the 3⁄4-ton, standard cab pickup was a reasonable surrogate for light truck vehicles, and there was a tremendous amount of experience and investment in designing for and test- ing with this truck. The implications of specifying the heavier, 5000-lb, 3⁄4-ton pickup truck as the new design test vehicle were not completely understood, but it was known that it would be more critical than the ex- isting 4409-lb, 3⁄4-ton pickup used under NCHRP Report 350. The 13 percent increase in weight and impact severity would place more demand on the structural adequacy of barrier systems and would aggravate problems with vehicle stability and occu- pant compartment deformation. As an example, it was demonstrated in a full-scale crash test that stan- dard strong steel post W-beam guardrail would not accommodate the new vehicle under Test Level 3 (TL-3) impact conditions. It was not until well into the development of MASH that the design test vehicle changed to a 5000-lb, 1⁄2-ton, 4-door pickup truck. The rationale for this change is that this body style pickup has char- acteristics that more closely resemble large SUVs than the 3⁄4-ton, standard cab pickup. Subsequent crash testing and analyses conducted under NCHRP Proj- ect 22-14(02) and other projects indicate that the 5000-lb, 1⁄2-ton, 4-door, pickup truck will impart impact loads that are comparable to those of the 4409-lb, 3⁄4-ton, standard cab pickup. Further, the 1⁄2-ton, 4-door, pickup truck appears to be more sta- ble and have less propensity for occupant com- partment intrusion than the 3⁄4-ton pickup. When these vehicle factors are combined with much more liberal thresholds for occupant compart- ment deformation, the need for revising existing hard- ware to comply with MASH does not appear to be as extensive as once anticipated. This fact is reflected in the performance assessment ratings assigned to the hardware assessed. The researchers do note that the dramatic increase in impact severity of the pickup truck redirection tests and other changes in the test matrices for terminals and crash cushions will likely necessitate the modification of some of these systems. However, most of these devices are proprietary in nature and therefore, an assessment of their per- formance has not been addressed under NCHRP Project 22-14(03). In addition to changes in the pickup truck vehicle, the test conditions for TL-4 have changed signifi- cantly. Most notably, the weight for the single-unit truck (SUT) vehicle increased from 17,640 lb to 22,050 lb and the impact speed increased from 50 mi/h to 56 mi/h. The increased weight and speed of the SUT vehicle increased the impact severity of longitu- dinal redirection test 4-12 by 56 percent. In addition, the estimated impact force of 76 kips for MASH test 4-12 represents a 41 percent increase from the 54-kip design load used for NCHRP Report 350 test 4-12. Consequently, some barriers that meet the NCHRP Report 350 guidelines as a TL-4 barrier may not have adequate strength to comply with the same test level under MASH. Another aspect of the structural adequacy criteria is that the test vehicle should not override the barrier. Adequate barrier height is required to prevent heavy trucks with high centers of gravity from rolling over a barrier. Full-scale crash testing has shown that 32-in. tall barriers are capable of meeting TL-4 impact conditions under NCHRP Report 350. How- ever, when MASH test 4-12 was conducted on a 32-in. tall New Jersey safety shape concrete bar- rier, the SUT rolled over the top of the barrier. After the unsatisfactory outcome of the test per- formed under Project 22-14(02), it was proposed to reduce the center-of-gravity (C.G.) height of the ballast of the SUT from 67 in. to 63 in. This effec- tively decreases the overturning moment by decreas- ing the moment arm between the C.G. of the truck and the reactive force applied by the barrier. Addi- 2

tional testing was performed under this project to determine whether the decrease in C.G. height was sufficient to permit 32-in. tall barriers to contain the SUT or whether taller barriers would be needed to comply with MASH. Testing under this project demonstrated that the decrease in ballast C.G. height was not sufficient to prevent the SUT from rolling over a 32-in. tall New Jersey safety shape barrier. State DOTs make considerable use of non- proprietary roadside safety systems. Although some barrier testing was conducted under NCHRP Project 22-14(02) during the development of the MASH criteria, many barrier systems and other roadside safety features have yet to be evaluated under the proposed guidelines. Therefore, evalua- tion of the remaining widely used roadside safety features following the impact performance require- ments of MASH was needed. Under this research project, researchers conducted a survey of the state DOTs for use and frequency rates for non-proprietary hardware and reviewed the test reports of the crash tests performed under NCHRP Project 22-14(02) and TXDOT project FHWA/TX-07/0-5526-1, as well as numerous tests performed under NCHRP Report 350 guidelines. A performance assessment of existing roadside safety devices was performed to help evaluate the impact of adopting MASH. Crash test results, engineering analyses, and engineering judgment were used to assist with the hardware evaluation. Categories of roadside features that were considered under the project include guardrail, median barriers, transitions from approach guard fence to barriers, breakaway sign supports, and precast and permanent concrete barriers. Proprietary devices were not considered. The manufacturers of these devices will be required to assess the impact performance of their devices and ultimately demonstrate compliance of their devices with the new test and evaluation guidelines. Results of the performance assessment were used to develop a prioritization scheme for further testing and evaluation required to bring roadside safety fea- tures into compliance with the new impact perfor- mance guidelines. PHASE II RESEARCH—FULL-SCALE CRASH TESTING The objective of Phase II of this project was to evaluate the safety performance of widely used non- proprietary roadside safety hardware using MASH performance and evaluation criteria. Highway safety hardware proposed for evaluation included longitu- dinal barriers (excluding bridge railings); terminals and crash cushions; transitions; and breakaway sign supports that had previously been accepted under NCHRP Report 350. Researchers identified use and frequency of spe- cific non-proprietary roadside safety hardware by surveying the state DOTs. In conjunction with the NCHRP project panel, a final test matrix consisting of nine roadside safety hardware features was chosen from 89 identified non-proprietary roadside safety hardware features. Researchers performed a total of 10 full-scale crash tests on nine different types of roadside safety hardware. New Jersey Safety Shape Barrier Test 4-12 Test Vehicle: 1999 Ford F-800 single-unit truck Test Inertia Weight: 22,090 lb Gross Static Weight: 22,090 lb Impact Speed: 57.4 mi/h Impact Angle: 14.4 degrees The 32-in. New Jersey safety shape bridge rail failed to contain and redirect the SUT vehicle under the new TL-4 impact conditions with a ballast C.G. height of 63 in. The SUT rolled 101 degrees before exiting the end of the barrier. Although subsequent contact with the ground enabled the vehicle to right itself as it came to rest, there is no question that the SUT would have continued to roll over the top of the rail had the barrier test installation length been longer. The 32-in. New Jersey safety shape bridge rail failed to demonstrate satisfactory performance according to the TL-4 evaluation criteria in MASH. Test 3-11 Test Vehicle: 2007 Chevrolet Silverado 4-door pickup Test Inertia Weight: 5049 lb Gross Static Weight: 5049 lb Impact Speed: 62.6 mi/h Impact Angle: 25.2 degrees The New Jersey safety shape barrier contained and redirected the 2270P vehicle under TL-3 impact conditions. The vehicle did not penetrate, underride, or override the installation. No measurable deflection 3

of the barrier occurred. No detached elements, frag- ments, or other debris were present to penetrate or to show potential for penetrating the occupant com- partment or to present hazard to others in the area. Maximum occupant compartment deformation was 2.0 in. at the right kickpanel. The 2270P vehicle remained upright during and after the collision event. Maximum roll and pitch angles were 29 and −16 degrees, respectively. Occupant risk factors were within the limits specified in MASH. The 2270P exited the barrier within the exit box. The New Jersey safety shape barrier performed acceptably when impacted by the 2270P vehicle (2007 Chevrolet Silverado pickup) and evaluated in accordance with the safety-performance evaluation criteria presented in MASH. G4(2W) W-Beam Guardrail Test Vehicle: 2007 Chevrolet Silverado 4-door pickup Test Inertia Weight: 5009 lb Gross Static Weight: 5009 lb Impact Speed: 64.4 mi/h Impact Angle: 26.1 degrees The G4(2W) W-beam guardrail did not perform acceptably when impacted by the 2270P vehicle (2007 Chevrolet Silverado pickup). The vehicle pen- etrated the guardrail after the W-beam rail element ruptured and then subsequently rolled 180 degrees. It should be noted that the impact speed and angle for this test were 64.4 mi/h and 26.1 degrees, respec- tively. The impact speed and angle were within the acceptable limits prescribed in MASH. However, the impact condition represented an impact severity 16.4 percent greater than the target MASH condition (62.2 mi/h and 25 degrees). Various modifications to W-beam guardrail have demonstrated improved performance. Modifications that have demonstrated improved performance in crash tests include increasing the rail height to 31 in., moving the rail splices to mid-span of the posts, and using 12-in. deep block-outs. It is believed that any one or more of these changes will improve the per- formance of the G4(2W) W-beam guardrail. Addi- tionally, it is known that W-beam guardrail has his- torically been performing at or very near 100 percent of structural design capacity. If the speed and angle in the test were nearer to target impact conditions, the rail may not have ruptured. G4(1S) W-Beam Median Barrier Test-3-10 Test Vehicle: 2002 Kia Rio Test Inertia Weight: 2418 lb Gross Static Weight: 2584 lb Impact Speed: 61.4 mi/h Impact Angle: 26.0 degrees The G4(1S) W-beam median barrier contained and redirected the 1100C vehicle. The vehicle did not penetrate, override, or underride the installation. Max- imum dynamic deflection was 11.25 in. No detached elements, fragments, or other debris were present to penetrate or to show potential for penetrating the occupant compartment or to present a hazard to others in the area. Maximum occupant compartment defor- mation was 2.0 in. in the left front driver’s area at the level of the floor pan. The 1100C vehicle remained upright during and after the collision event. Maximum roll angle was 8 degrees. Occupant risk factors were within the limits specified in MASH. The 1100C vehi- cle exited the median barrier within the exit box. The G4(1S) W-beam median barrier performed acceptably when impacted by the 1100C vehicle (2002 Kia Rio). Test-3-11 Test Vehicle: 2007 Chevrolet Silverado 4-door pickup Test Inertia Weight: 5029 lb Gross Static Weight: 5029 lb Impact Speed: 64.0 mi/h Impact Angle: 25.1 degrees The G4(1S) W-beam median barrier did not per- form acceptably when impacted by the 2270P vehi- cle (2007 Chevrolet Silverado pickup). The 2270P Silverado pickup truck overrode the installation. It should be noted that the impact speed and angle for this test were 64.0 mi/h and 25.1 degrees, respec- tively. The impact speed and angle were within the acceptable limits prescribed in MASH. However, the impact condition represented an impact severity 7.5 percent greater than the target MASH condition (62.2 mi/h and 25 degrees). If the speed and angle in the test were nearer to target impact conditions, the vehicle may not have vaulted over the test installation. Typically, when the G4(1S) W-beam barrier is impacted in a roadside application, the support posts displace through the soil and help dissipate the energy 4

of the impacting vehicle. When the displacement or deformation of the post becomes large enough, the rail detaches from the post by means of the post bolt pulling out of the rail slot. However, in the G4(1S) W-beam median barrier, the addition of the rear W-beam rail element provides additional stiffness and constrains the lateral displacement of the posts. Because the rail cannot readily detach from the posts, the rail is pulled down by the posts and the effective rail height is reduced in the region of impact. In the test presented herein, a guardrail post was impacted by the left front tire and the vehicle climbed the post and W-beam rail element. A 30-in. tall version of the G4(1S) W-beam median barrier (AASHTO Designation SGM06a-b) incorporates a C6x8.2 rub-rail channel that is mounted 12 in. above the ground to the center of the rub-rail. The addition of the rub-rail will prevent the wheel from contacting the face of the posts and thus help mitigate vehicle-post snagging. The rub-rail will also increase the barrier stiffness, which should reduce post displacement and rail deflection. However, the rub- rail may still permit the pickup to climb the barrier. The researchers recommend evaluating the 30-in. tall G4(1S) W-beam median barrier (AASHTO Des- ignation SGM06a) with MASH Test 3-11. W-Beam Transition Test Vehicle: 2007 Chevrolet Silverado 4-door pickup Test Inertia Weight: 5029 lb Gross Static Weight: 5029 lb Impact Speed: 62.8 mi/h Impact Angle: 25.7 degrees The W-beam transition to concrete bridge para- pet successfully contained and redirected the 2270P vehicle. The vehicle did not penetrate, override, or underride the installation. Maximum dynamic deflection was 3.8 in. No detached elements, frag- ments, or other debris were present to penetrate or to show potential for penetrating the occupant com- partment or to present a hazard to others in the area. Maximum occupant compartment deformation was 0.6 in. in the left rear area at hip height. The 2270P vehicle remained upright during and after the col- lision event. Maximum roll angle was 54 degrees. Occupant risk factors were within the limits specified in MASH. The 2270P vehicle exited the W-beam tran- sition within the exit box. The W-beam transition to concrete parapet per- formed acceptably when impacted by the 2270P vehicle (2007 Chevrolet Silverado 4-door pickup). Sign Supports Test Vehicle: 2003 Dodge Ram 1500 quad-cab pickup Test Inertia Weight: 4958 lb Gross Static Weight: 4958 lb Impact Speed: 63.3 mi/h Impact Angle: 0 degrees The U-channel and perforated square steel tube (PSST) small sign supports both readily activated upon impact by the 2270P vehicle by fracturing at bumper height and at the ground stub interface. The detached sign supports rotated around the front of the vehicle, and the sign panels struck near or at the windshield and roof area and subsequently traveled with the vehicle. The 2270P vehicle remained upright during and after both collision events. Minimal roll and pitch were noted. Occupant risk factors were within acceptable limits. The 2270P vehicle came to rest behind the test articles. Contact of the U-channel support with the wind- shield and roof was minimal, and the support did not penetrate nor show potential for penetrating the occu- pant compartment. The largest detached piece of this support weighed 33.6 lb, but the trajectory was rel- atively low and should not cause undue hazard to others in the area. No occupant compartment defor- mation related to impact with the U-channel support was measured. The upper section of the PSST support and sign panel contacted and shattered the windshield. No tear of the windshield plastic lining occurred. However, the windshield was deformed inward 3.5 in. MASH (Section 5.3 and Appendix E) limits deformation of the windshield to 3 in. The 4 lb/ft steel U-channel support manufactured by NuCor Steel Marion successfully met the MASH evaluation criteria for Test 3-62. The 12-gauge per- forated, 2-in. square, steel tube (PSST) support manufactured by Northwest Pipe failed to meet the MASH evaluation criteria for Test 3-62 due to excessive occupant compartment deformation at the windshield. The primary observed difference in the perfor- mance of the two sign support types is the manner in which the sign panel reacted during the impact 5

sequence. Both sign support types fractured at bumper height and near the ground stub interface. The U-channel sign support installation kept the sign panel attached to the support for much of the impact event. The sign panel remained attached until the support and panel impacted the roof of the truck as an assembly. Upon separation, both the sign and support passed over the cab of the pickup truck. During the test of the PSST sign support, the sign panel released from the support at approximately the same time the support failed at bumper height. The failure of the sign attachment and release of the sign panel changed the dynamics of the impact and per- mitted the sign panel to impact the windshield more directly. The PSST sign support stayed in the front of the vehicle and displaced forward with the vehicle with very little angular momentum. It is the opinion of the researchers that had the sign panel remained attached to the support, the PSST sign support instal- lation performance would have been similar to the U-channel performance, and the PSST would have likely met the MASH performance evaluation criteria. Further testing with enhanced sign panel-to-post con- nection can be performed to verify this opinion. G3 Weak Post Box-Beam Guardrail Test Vehicle: 2007 Chevrolet Silverado 4-door pickup Test Inertia Weight: 5011 lb Gross Static Weight: 5011 lb Impact Speed: 63.2 mi/h Impact Angle: 25.4 degrees The G3 weak post box-beam guardrail contained and redirected the 2270P vehicle. The vehicle did not penetrate, underride, or override the weak post guardrail. Maximum dynamic deflection of the rail during the test was 4.8 ft. Two rail brackets detached from their posts, but they did not penetrate or show potential for penetrating the occupant compartment or present a hazard to others in the area. Maximum occupant compartment deformation was 0.75 in. in the lateral area across the cab at the driver’s side kick- panel. The 2270P vehicle remained upright during and after the collision event. Maximum roll angle was −14 degrees. Occupant risk factors were within the limits specified in MASH. The 2270P vehicle exited within the exit box. The G3 weak post box-beam guardrail performed acceptably when impacted by the 2270P vehicle (2007 Chevrolet Silverado pickup). Modified G2 Weak Post W-Beam Guardrail Test Vehicle: 2007 Chevrolet Silverado 4-door pickup Test Inertia Weight: 5004 lb Gross Static Weight: 5004 lb Impact Speed: 62.4 mi/h Impact Angle: 24.6 degrees The modified G2 weak post W-beam guardrail contained and redirected the 2270P vehicle. The vehicle did not penetrate, underride, or override the weak post W-beam guardrail. Maximum dynamic deflection of the rail during the test was 8.6 ft. There was no debris from the test installation that pene- trated or showed potential for penetrating the occu- pant compartment or presented a hazard to others in the area. Maximum occupant compartment defor- mation was 0.25 in. in the lateral area across the cab at the driver’s side hip area. The 2270P vehicle remained upright during and after the collision event. Maximum roll angle was −12 degrees. Occupant risk factors were within the limits specified in MASH. The 2270P vehicle remained within the exit box. The modified G2 weak post W-beam guardrail performed acceptably when impacted by the 2270P vehicle (2007 Chevrolet Silverado pickup). G9 Thrie Beam Guardrail Test Vehicle: 2007 Chevrolet Silverado 4-door pickup Test Inertia Weight: 5019 lb Gross Static Weight: 5019 lb Impact Speed: 63.3 mi/h Impact Angle: 26.4 degrees The G9 thrie beam guardrail did not perform acceptably when impacted by the 2270P vehicle (2007 Chevrolet Silverado pickup). After being con- tained and redirected, the 2270P Silverado pickup rolled 360 degrees. Maximum dynamic deflection of the thrie beam during the test was 33.2 in. Maximum occupant compartment deformation was 3.56 in. in the right rear passenger area. It should be noted that the impact speed and angle for this test were 63.3 mi/h and 26.4 degrees, respectively. The impact speed and angle were within the acceptable limits prescribed in MASH. However, the impact condition represented an impact severity 15.3 percent greater than the target MASH condition (62.2 mi/h and 25 degrees). If the speed and angle in the test were nearer to target impact conditions, the vehicle may not have rolled over. 6

CONCLUSION Nine different types of roadside safety hard- ware were crash tested and evaluated in accordance with MASH. Six of the 10 crash tests performed on these nine safety devices successfully met the MASH evaluation criteria. Table 1 summarizes the non- proprietary roadside safety hardware tested under NCHRP Projects 22-14(02) and 22-14(03) that suc- cessfully met the MASH evaluation criteria. Table 2 identifies the non-proprietary roadside safety hard- ware tested under these projects that failed to meet the MASH evaluation criteria. REPORT AVAILABILITY The complete report for NCHRP Project 22- 14(03) is available on TRB’s website (www.trb.org) as NCHRP Web-Only Document 157. Copies of the crash test reports (Appendices B through K) are available on the National Crash Analy- sis Center website (www.nac.gwu.edu). ACKNOWLEDGMENTS This study was conducted under NCHRP Project 22-14(03), “Evaluation of Existing Roadside Safety Hardware Using Updated Criteria.” It was guided by NCHRP Project Panel 22-14, chaired by Ronald J. Seitz, with the following members: Richard B. Albin, James Buchan, Mack O. Christensen, Keith A. Cota, F. Daniel Davis, John C. Durkos, H. Clay Gabler, David L. Little, Howard M. McCulloch, Leonard Meczkowski, Barry Stephens, Harry W. Taylor, Jr., Steven E. Walker, Kenneth S. Opiela, and Stephen F. Maher. 7

8Ref. Vehicle Impact Impact Test Agency Test Test Test Vehicle Make Mass Speed Angle OIV Ridedown No.* No. Designation Article and Model (lb) (mph) (deg) (ft/s) (G) 1 2 3 4 5 6 7 8 Table 1 Crash tests performed under NCHRP Project 22-14 that met MASH (passed). 2214WB-11 2214WB-2 2214MG-1 2214MG-2 2214MG-3 2214TB-1 2214TB-2 2214NJ-1 3-11 3-11 3-11 3-11 3-10 3-11 3-11 3-10 Modified G4(1S) Guardrail Modified G4(1S) Guardrail Midwest Guardrail System (MGS) MGS MGS (Max. Height) Free-Standing Temporary F-Shape Barrier Free-Standing Temporary F-Shape Barrier 32-in. Permanent New Jersey Safety Shape Barrier 2002 GMC 2500 3⁄4-ton Pickup 2002 Dodge Ram 1500 Quad Cab Pickup 2002 GMC 2500 3⁄4-ton Pickup 2002 Dodge Ram 1500 Quad Cab Pickup 2002 Kia Rio 2002 GMC 2500 3⁄4-ton Pickup 2002 Dodge Ram 1500 Quad Cab Pickup 2002 Kia Rio 5000 5000 5000 5000 2588 5000 5000 2579 61.1 62.4 62.6 62.8 60.8 61.8 61.9 60.8 25.6 26.0 25.2 25.5 25.4 25.7 25.4 26.1 X = 17.3 Y = 16.2 X = 17.6 Y = 13.1 X = 17.1 Y = 14.8 X = 15.3 Y = 15.6 X = 14.8 Y = 17.1 X = 18.5 Y = 18.9 X = 17/0 Y = 17/3 X = 16.5 Y = 35.0 X = −19.7 Y = −8.5 X = 6.9 Y = −6.6 X = −8.8 Y = −5.3 X = −8.2 Y = −6.9 X = −16.1 Y = −8.4 X = −11.9 Y = −6.5 X = −7.2 Y = −11.4 X = −5.5 Y = −8.1

99 10 13 14 15 16 17 18 1Rail ruptured. Passed by FHWA. 2214T-1 2214TT-1 476460-1-4 476460-1-2 476460-1-3 476460-1-6 476460-1-7 476460-1-10 3-21 3-34 3-11 3-62 3-21 3-11 3-11 3-10 Guardrail to Concrete Barrier Transition Sequential Kinking Terminal (SKT)- MGS (Tangent) 32-in. Permanent New Jersey Safety Shape Barrier 4 lb/ft U-Channel Sign Support W-Beam Transition G3 Weak Post Box- Beam Guardrail G2 Weak Post W-Beam Guardrail G4(1S) W-Beam Median Barrier 2002 Chevrolet C1500HD Crew Cab Pickup 2002 Kia Rio 2007 Chevrolet Silverado Pickup 2003 Dodge Ram 1500 Quad Cab Pickup 2007 Chevrolet Silverado Pickup 2007 Chevrolet Silverado Pickup 2007 Chevrolet Silverado Pickup 2002 Kia Rio 5083 2597 5049 4958 5029 5011 5004 2584 60.3 64.4 62.6 63.3 62.8 63.2 62.4 61.4 24.8 14.5 25.2 0 25.7 25.4 24.6 26.0 X = 24.4 Y = 25.0 X = 17.8 Y = 13.4 X = 14.1 Y = 30.2 No contact X = 16.4 Y = 28.5 X = 11.2 Y = 15.1 X = 9.5 Y = 10.5 X = 16.4 Y = 24.3 X = 12.7 Y = 8.7 X = −7.5 Y = −9.1 X = −5.6 Y = −9.6 N/A X = −8.1 Y = 16.4 X = −5.7 Y = 7.2 X = −3.4 Y = 4.5 X = −16.5 Y = 10.5

10 Ref. Vehicle Impact Impact Test Agency Test Test Vehicle Make Mass Speed Angle OIV Ridedown Mode of No.* Test No. Designation Article and Model (lb) (mi/h) (deg) (ft/s) (G) Failure 11 12 15 19 20 21 Table 2 Crash tests performed under NCHRP Project 22-14 that did not meet MASH (failed). 2214NJ-2 476460-1b 476460-1-2 476460-1-5 476460-1-8 476460-1-9 4-12 4-12 3-62 3-11 3-11 3-11 32-in. Permanent New Jersey Safety Shape Barrier 32-in. Permanent New Jersey Safety Shape Barrier Perforated Square Steel Tube Sign Support G4(2W) W-Beam Guardrail G9 Thrie Beam Guardrail G4(1S) W-Beam Median Barrier 1989 Ford F-800 1999 Ford F-800 2003 Dodge Ram 1500 Quad Cab Pickup 2007 Chevrolet Silverado Pickup 2007 Chevrolet Silverado Pickup 2007 Chevrolet Silverado Pickup Truck rolled over rail Truck rolled over rail Excessive deformation Pickup pene- trated and rolled Pickup rolled Penetrated rail element 22,045 22,090 4958 5009 5019 5029 56.5 57.4 61.7 64.4 63.3 64.0 16.2 14.4 0 26.1 26.4 25.1 X = 6.5 Y = 13.6 X = 8.2 Y = 13.8 X = 4.3 Y = 2.3 X = 21.6 Y = 14.1 X = 17.1 Y = 17.4 X = 17.2 Y = 17.1 X = −22.4 Y = −8.8 X = −4.3 Y = 7.7 X = −08 Y = −0.4 X = −10.2 Y = 9.6 X = −6.9 Y = 7.7 X = −5.2 Y = 5.3

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