Roadside Barrier Designs near Bridge Rail Ends with Restricted Rights-of-Way: A National Survey and Testing Reports (2022)

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185 Appendix G Test Report • FOIL • Test 20004 • MASH Test 3-33 Retest CRASH TEST EVALUATION OF A SHORT-RADIUS BARRIER FOR APPLICATION NEAR BRIDGE ENDS FOR THE MASH 3-33 RETEST TEST CONDITION Authors: Dhafer Marzougui, Christopher Story, Kenneth Opiela Fadi Tahan, and Cing-Dao (Steve) Kan Center for Collision Safety and Analysis George Mason University FOIL Test No. 20004 CCSA Report No. R-20004

186 SUMMARY This appendix reports the result of a crash test described below: Report Title Crash Test Evaluation of a Short-Radius Barrier for Application Near Restricted Bridge Ends Test Type Full-Scale Crash Test: Vehicle Impacting Barrier What is Tested Short-Radius Guardrail System (SRGS) Purpose/Objective For situations where there are access constraints that limit the normal type of end treatments (such as bridge next to intersecting roadway). Impacting Item/Vehicle 2270P MASH pickup truck-type vehicle. Impact Speed and Conditions Speed 62 mph, centerline of the vehicle aligned 15 degrees to the main roadway, impacting the nose of the system with a level surface behind the system. Test Procedures and Standards Information Manual for Assessing Safety Hardware (MASH), 2016 edition Test Criteria TL-3 Impact Rating for Condition 3-33 Test Number FOIL Test No. 20004 Test Date March 20, 2020 Test Location Federal Outdoor Impact Laboratory (FOIL) Turner-Fairbank Highway Research Center (TFHRC) FHWA U.S. DOT 6300 Georgetown Pike, McLean, VA 22101-2296 Conducted by Center for Collision Analyses and Safety (CCSA) George Mason University (GMU) 4087 University Drive, Fairfax, VA 22030 Report Authors Dhafer Marzougui, Christopher Story, Kenneth Opiela Fadi Tahan, and Cing-Dao (Steve) Kan Test Results Summary MASH Test 3-33 Retest. Test 20004. Pickup truck was captured and brought to a controlled stop within the system. PASSED MASH requirements.

187 TABLE OF CONTENTS SUMMARY ................................................................................................................................ 185 TABLE OF CONTENTS .......................................................................................................... 187 LIST OF FIGURES ................................................................................................................... 188 LIST OF TABLES ..................................................................................................................... 188 1.0. INTRODUCTION ........................................................................................................ 189 1.1. PROBLEM STATEMENT ............................................................................................. 189 1.2. STUDY OBJECTIVES ................................................................................................. 189 1.3. SCOPE OF STUDY ...................................................................................................... 190 2.0. SYSTEM DETAILS ........................................................................................................... 190 2.1. TEST ARTICLE AND INSTALLATION DETAILS ........................................................... 190 2.2. MATERIAL SPECIFICATIONS ..................................................................................... 197 2.3. SOIL CONDITIONS ..................................................................................................... 197 3.0. MASH TEST REQUIREMENTS AND ACCEPTANCE CRITERIA ......................... 197 4.0. TEST CONDITIONS ......................................................................................................... 198 4.1. FOIL TEST FACILITY ................................................................................................ 198 4.2. VEHICLE TOW AND GUIDANCE PROCEDURES .......................................................... 198 4.3. TEST VEHICLE PREPARATION .................................................................................. 200 4.4. DATA ACQUISITION SYSTEMS .................................................................................. 200 4.5. TEST SET-UP CONDITIONS ........................................................................................ 200 5.0. CRASH TEST DOCUMENTATION ............................................................................... 204 5.1. TEST DESIGNATION AND IMPACT CONDITIONS ....................................................... 204 5.2. CRASH TEST 20004 OUTCOME (FOR MASH TEST 3-33 RETEST) ............................ 204 5.3. TEST ARTICLE AND VEHICLE DAMAGE ................................................................... 204 5.4. MASH EVALUATION ................................................................................................ 213 6.0. CONCLUSIONS AND RECOMMENDATIONS ........................................................... 215 6.1 SUMMARY AND CONCLUSIONS ................................................................................. 215 6.2 RECOMMENDATIONS ................................................................................................. 215 7.0. REFERENCES ................................................................................................................... 215

188 LIST OF FIGURES Figure 1. SRGS (modified) Test Installation diagram with main road side profile and details. ..............192 Figure 2. SRGS Test Installation diagram showing side road features (horizontal portion). ..................193 Figure 3. Details of cable connectors to control detachment of barrier components. ............................196 Figure 4. Aerial view of FHWA FOIL layout. ..................................................................................199 Figure 5. Diagram of system installation for SRGS tests. ...................................................................199 Figure 6. Test 3-33 Retest (Test 20004) pre-impact photos showing condition and setup of test vehicle. ........................................................................................................................201 Figure 7. Test 3-33 Retest (Test 20004) pre-impact condition views of SRGS. ....................................202 Figure 8. Test 3-33 Retest (Test 20004) pre-impact views of test vehicle relative to SRGS. .................203 Figure 9. Test 3-33 Retest (Test 20004) impact point and angle. ........................................................204 Figure 10. Test 3-33 Retest (Test 20004) post-impact condition of vehicle. ........................................206 Figure 11. Test 3-33 Retest (Test 20004) post-impact condition of SRGS. ..........................................207 Figure 12. Test 3-33 Retest (Test 20004) post-impact condition of vehicle and SRGS. ........................208 Figure 13. Test 3-33 Retest (Test 20004) sequential images—view of impact from right side. .............209 Figure 14. Test 3-33 Retest (Test 20004) sequential images—view of impact from behind SRGS. .......210 Figure 15. Test 3-33 Retest (Test 20004) sequential images—view of impact from left side. ...............211 Figure 16. Test 3-33 Retest (Test 20004) variations in x-, y-, and z-accelerations at CG. .....................212 Figure 17. Test 3-33 Retest (Test 20004) measured roll, pitch, and yaw angle plots. ............................213 Figure 18. Test 3-33 Retest (Test 20004) summary sheet for crash test results. ...................................216 LIST OF TABLES Table 1. SRGS Test Installation Components. ..................................................................................194 Table 2. MASH tests conducted for the Short-Radius W-beam Guardrail System (SRGS) ...................197 Table 3. Test 3-33 evaluation requirements by category. ...................................................................198 Table 4. Events during Test 3-33 Retest (Test 20004). ......................................................................205 Table 5. Occupant Risk Factors—Test 3-33 Retest (Test 20004). .......................................................213 Table 6. Review of MASH results for Test 3-33 Retest for FOIL Test 20004. .....................................214

189 1.0. INTRODUCTION 1.1. Problem Statement An objective of the U.S. Department of Transportation and the many state departments of transportation is to promote the highest level of safety for highway users. Safety is addressed in many ways, including roadway design and adjacent areas to prevent or mitigate adverse consequences of single or multiple vehicle crashes. Guardrail installations are a common treatment used to safely redirect errant vehicles back onto the roadway or away from hazards that may exist beyond the edge of the roadway. Guardrail treatments are commonly seen along highways, but there are many other types of Roadside Safety Hardware (RSH) that serve similar purposes. These treatments have evolved as safety needs became apparent and efforts continue to enhance RSH effectiveness and seek solutions for other potential roadway safety hazards. One long-time situation of concern is usually found on rural highways where the need to provide a safe transition into a bridge rail is restricted by the need to provide access to intersecting roads. Typically, a short-radius curved guardrail section has been installed to add a measure of safety. An early version of a short-radius barrier passed the NCHRP Report 230: Recommended Procedures for the Safety Performance Evaluation of Highway Appurtenances safety criteria, and later some additional designs were developed and tested based on more rigorous MASH requirements. Appendix A describes each of these developments. The tight conditions, the multiple ways the short-radius barrier can be hit, and evolving higher safety requirements have posed an unresolved challenge to develop a better barrier for such applications. Broader agency concerns over liability associated with crashes have generated a new emphasis on the need to develop a crashworthy device for such situations. That concern motivated NCHRP Project 15-53, “Roadside Barrier Designs Near Bridge Ends with Restricted Rights-of-Way,” which is designed to address this problem and develop an upgraded barrier. The FHWA also made the staff, resources, and equipment of the FOIL available to support this NCHRP project. These efforts are being documented in a comprehensive NCHRP report, NCHRP Research Report 1013: Roadside Barrier Designs near Bridge Rail Ends with Restricted Rights-of-Way: A Guide. This appendix provides details of one of four crash tests conducted in accordance with MASH protocols to certify that the barrier meets current safety requirements. 1.2. Study Objectives The objective of this effort was to develop a modified or new barrier to address the unique need for a transition to a rigid bridge rail where nearby access roads limit the normal approaches to provide a transition to the bridge rail. This need often occurs on rural roads, which carry lower traffic volumes. NCHRP Project 15-53, “Roadside Barrier Designs Near Bridge Ends with Restricted Rights-of-Way,” was awarded to a team of KLS Engineering and the George Mason University CCSA to analyze the needs and develop a viable solution. To evaluate previous efforts and find viable solutions for such situations, CCSA used crash simulations to review and evaluate the alternative designs formulated until a viable design was achieved. Researchers analyzed previous designs to isolate problems and potentials problems that could be encountered with evolving higher crashworthiness requirements. Adding to the challenge were the limited resources available for an economical design. Ultimately, a design evolved that provided the rigidity needed near the bridge rail that transferred the impacts to the

190 perpendicular section of the barrier and shielded the area of concern. CCSA used simulations to test strategic stiffening and weakening options. Viable options were refined until there was confidence that a Test Level 3 short-radius barrier could be fabricated. Refining simulations incrementally followed testing and led to a workable design that would meet MASH requirements. 1.3. Scope of Study It was determined that that evaluation of this device would require successful passing of several MASH tests including Tests 3-31, 3-32, 3-33, and 3-35. This appendix provides the background and results for FOIL Test 20004 (MASH Test 3-33 Retest) of the modified system. The test installation consisted of a 31-inch tall, approximately 76 ft long, 10-gauge W-beam SRGS that connects to a transition section to a bridge rail on the main road and to a standard cable anchor on the side road. 2.0. SYSTEM DETAILS 2.1. Test Article and Installation Details Figures 1 and 2 show the MASH TL-3 SRGS test installation design developed under this project. The figures depict the system along the main road attaching to an 18 ft 9 in. long Thrie- beam transition design connected to a concrete parapet. The transition consisted of: • A 10-gauge Thrie-beam terminal connector (RTE01b), • A single 12 ft 6 in. 10-gauge Thrie-beam rail (RTM08b), and • A Thrie-beam asymmetrical section (RWT02). The system attaches on the side road to a cable end anchor (without the ground strut). The SRGS involves of the following elements: • A 31 in. high, 6 ft 3 in. long 10-gauge W-beam rail (RWM01b) with 6 ft long steel posts (PWE01) spaced at 37 ½ in. and 8 in. routed wood blockouts (PDB01b) connected to the asymmetrical section (W-beam to Thrie-beam). • For the radius, the system uses a 12 ft. 6 in. long, 10-gauge W-beam (RWM04b) section, curved 90 degrees with an 8 ft radius and 6 ft long steel posts (PWE01) spaced at 37 ½ in., with 8 in. routed wood blockouts (PDB01b). • The first, center, and last posts in the curved section are not connected to the rail in this design - to control the deformation of the barrier under impact. • Along the side road, the system consists of two 12 ft 6 in. long straight 10-gauge W-beam (RWM04b) sections with 6 ft long steel posts (PWE01). The first post from the radius is spaced at 37 ½ in., and the remaining posts are spaced at 6 ft 3 in. All posts use 8 in. routed wood blockouts (PDB01b). In addition, two cables run along the entire system (and anchor outside of the system - to the end of the bridge rail transition along the main road and to the anchor along the side road). Each end of the cables require a cable end fitting:

191 • The top cable is placed along the front side in the center valley of the W-beam from the top valley of the Thrie-beam (RTM08b) section to the end of the barrier on the side road. The cable is attached to the back side of the Thrie-beam with half of a standard anchor bracket after threading through a field-drilled slot in the top valley. The cable is anchored on the back side of the end anchor W-beam on the side road, again threading through a field-drilled slot in the center valley of the 10-guage W-beam, with half of a standard anchor bracket located prior to the full anchor bracket used with the guardrail cable end anchor. • The bottom cable is mounted 5 in. below the W-beam, threaded through 5/8-in diameter eyebolts spaced at either 12 ½ in. or 20 ¾ in. The cable is anchored with half of an anchor bracket in the lower valley on the back side of the Thrie-beam (RTM08b) and then connected with a bearing plate and nut on the second post of the end anchor along the side road. All holes for the standard eyebolts were field-drilled and the eyebolts are anchored in the rail with a nut and washer on each side of the rail. The SRGS was modified by adding an additional 18 ft 9 in. of 10-gauge W-beam rail attached to the back of the Thrie-beam, the asymmetrical section, and 37 ½ in. of the W-beam along the main road. The added rails were directly connected to the transition posts without blockouts. An added rounded end section (RWE03a) shields the upstream end of the back rail and was bolted to the back side of the W-beam. Table 1 provides a summary of the standard barrier hardware parts used for this design and to make it possible for agencies to readily fabricate this barrier. No special parts are required. Figure 3 shows various views of the cable connections included to prevent vehicle penetration and underride in a crash.

192 Figure 1. SRGS (modified) Test Installation diagram with main road side profile and details. (R W T0 2) (R TM 08 b)

193 Figure 2. SRGS Test Installation diagram showing side road features (horizontal portion).

194 Table 1. SRGS Test Installation Components. Element Designations and Notes TF13 Drawing Photo Transition Used for Testing Part RTE01b Thrie-beam Terminal Connector • 10 gauge • Thickness 3.43 mm Part RTM04a-b 8-Space Thrie-beam Guardrail • 10 gauge • Thickness 3.43 mm • Total Length 4130 mm • Post Spacing 476 mm Part RWT02 MGS W-beam to Thrie-beam Transition • 10 gauge • Thickness 3.43 mm • Total Length 2225 mm • Post Spacing 952 mm End Anchor used for Testing End Treatment (Ohio Anchor without the ground strut)

195 Table 1. SRGS Test Installation Components (cont’d). Element Designations and Notes TF13 Drawing Photo SRGS Elements Part RWM01a-b W-beam Spacer Guardrail • 10 gauge • Thickness 3.43 mm • Total Length 2225 mm • Post Spacing 952 mm Part RWM04a-b 4-Space W-beam Guardrail • 10 gauge • Thickness 3.43 mm • Total Length 4130 mm • Post Spacing 952 mm Cable Tether Linkage • Cable (19 mm dia.) RCM01 • Eyebolts (16 mm dia.) Cable-to-Rail Anchor • Anchor Bracket (FPA01 cut in half) • Cable (19 mm dia.) • Cable End Fitting (RCE 03) W-Beam End Section (Rounded) 12 gauge RWE03a • Thickness 2.67 mm

196 Top and Bottom cables attached to the Thrie-beam using ½ of a standard anchor bracket (Back View) Top and Bottom cables attached to the Thrie-beam using ½ of a standard anchor bracket (Front View) Field cut slot for the top cable Front view of both cables Front view of the Top and Bottom cables on the radius of the system Front view of the Top and Bottom cables on the side road. Field cut slot for the top cable Front view of the Top and Bottom cables on the side road. Lower cable anchored with a bearing plate. Back view of the Top cables on the side road using ½ of a standard anchor bracket Figure 3. Details of cable connectors to control detachment of barrier components.

197 2.2. Material Specifications This system was fabricated using standard RSH elements, as described above. The materials and hardware elements delivered met the basic standards in accordance with suppliers or certifications are on file at the FOIL Office. 2.3. Soil Conditions The posts for the SRGS were driven or bored in the designated positions in the impact area of the FOIL, as depicted. The soils at the FOIL have been classified as typical VDOT materials. Soil tests confirmed the compaction and moisture content of the soils were in appropriate ranges consistent with previous testing at the FOIL. These tests, conducted with a nuclear density device, involved repeated measures at multiple positions around the test installation. The FOIL Summary Report documents these results. The measurements confirmed that placing of the posts conformed to requirements. Independent soil analyses by Froehling & Robertson, Inc. are on file at the FOIL Office. 3.0. MASH TEST REQUIREMENTS AND ACCEPTANCE CRITERIA As noted in Table 2 below, researchers determined that overall evaluation of this device would require successful passing of several MASH tests. This appendix provides ONLY the background and results for MASH Test 3-33 Retest (FOIL Test 20004) on the modified system. Test 3-33 was considered critical as it involved the difficult containment of the large vehicle at the nose (center post of the radius) of the system on a 15 degrees line off the concrete parapet/transition to avoid penetrating the area behind the system. The other tests conducted at the FOIL facility in 2019 and 2020 addressed appropriate MASH requirements. All tests were setup and executed according to prescribed FOIL protocols (including facility ISO requirements) and MASH standards. These are individually documented in Test Reports (following MASH requirements). The table reflects variations in vehicles, speed, and angles for these tests. Table 2. MASH tests conducted for the SRGS Test Number Date MASH Test Vehicle Impact Speed Impact Angle Outcome 19008 08/09/19 3-31 Pickup Truck 100 km/hr 0 Pass 19010 08/20/19 3-32 Small Sedan 100 km/hr 15 Pass 19012 09/05/19 3-33 Pickup Truck 100 km/hr 15 Fail 20004 03/02/20 3-33 Retest Pickup Truck 100 km/hr 15 Pass 20008 09/16/20 3-35 Pickup Truck 100 km/hr 25 Pass 20012 11/04/20 3-33 Pickup Truck 80 km/hr 15 Pass Three criteria must be met under MASH requirements—various Structural Adequacy, Occupant Risk, and Vehicle Trajectory measures. Table 3 below notes the specific requirements for these criteria, and one or more specific requirements are outlined for each aspect.

198 Table 3. Test 3-33 evaluation requirements by category. Evaluation Category Requirement Structural Adequacy A. Test article should contain and redirect the vehicle or bring the vehicle to a controlled stop; the vehicle should not penetrate, underride, or override the installation, although controlled lateral deflection of the test article is acceptable. Occupant Risk D. Detached elements, fragments, or other debris from the test article should not penetrate or show potential for penetrating the occupant compartment, or present an undue hazard to other traffic, pedestrians, or personnel in a work zone. Deformation of, or intrusions into, the occupant compartment should not exceed limits set forth in Section 5.3 and Appendix E of MASH (roof ≤4.0 in.; windshield = ≤3.0 in.; side windows = no shattering by test article structural member; wheel/foot well/toe pan ≤9.0 in.; forward of A-pillar ≤12.0 in.; front side door area above seat ≤9.0 in.; front side door below seat ≤12.0 in.; floor pan/transmission tunnel area ≤12.0 in.). F. The vehicle should remain upright during and after collision. The maximum roll and pitch angles are not to exceed 75 degrees. H. Occupant impact velocities should satisfy the following: • Longitudinal and Lateral Occupant Impact Velocity Preferred Maximum: 30 ft/s to 40 ft/s. I. Occupant ridedown accelerations should satisfy the following: • Longitudinal and Lateral Occupant Ridedown Accelerations Preferred Maximum: 15.0 G to 20.49 G. Vehicle Trajectory For redirective devices, it is desirable that the vehicle be smoothly redirected and exit the barrier within the “exit box” criteria (not less than 32.8 ft), and should be documented. Vehicle rebound distance and velocity should be reported for crash cushions. 4.0. TEST CONDITIONS 4.1. FOIL Test Facility All testing on this system was performed at the FOIL. The FOIL is an ISO17025-accredited (Cert. # AT-1565) research facility used to support FHWA Safety Research and Development programs and other federal security initiatives. ISO 17025 identifies high technical competence and management system requirements that guarantee test results. It demonstrates the FOIL’s commitment to operational efficiency and quality management practices and verifies the quality, capability, and expertise of the FOIL. The FOIL is a multifaceted impact-testing facility, primarily designed to test the impacts of vehicles with RSH, in accordance with the MASH guidelines and standards. 4.2. Vehicle Tow and Guidance Procedures A specially designed FOIL hydraulic-propulsion system pulls the test vehicles into the barriers. The vehicles are accelerated on a 220 ft concrete track. The propulsion system is capable of pulling a 17,637 lbs. vehicle to over 50 mph. The 2270P test vehicle can be brought to speeds in excess of 70 mph. The test vehicles are released into a 160 x 320 ft runout area. Barriers up to

199 450 ft in length (usually at 25 degree relative to the track) can be installed in the runout area at the end of the track. Figure 4 provides an aerial view of the FOIL facility. Figure 4. Aerial view of FHWA FOIL layout. For the SRGS tests, the system was placed at an angle relative to the FOIL track to achieve the desired impact point and angle with the system. The system was installed adjacent to end of the track so the vehicle could be freewheeling and impact at the desired speed and point. Figure 5 depicts the orientations of the barrier relative to the track (i.e., road). The distance between the vehicle release point will consider the space needed to construct the full barrier and then calculate a release speed to achieve the desired impact velocity. These parameters are then incorporated in the test setup. Figure 5. Diagram of system installation for SRGS tests. FOIL Track Simulated Bridge End

200 4.3. Test Vehicle Preparation MASH Test 3-33 involved a 2270P vehicle weighing 5,000 lb. ±110 lb. impacting the test article at an impact speed of 62.2 mph ±2.5 mph and an angle of 15 ±1.5 degrees relative to the traffic face of the transition/bridge. The target impact point was the centerline of the truck at the nose of the radius, aligned with the traffic face of the concrete parapet/transition. The 2014 Dodge Ram 1500 quad-cab pickup truck used in the test weighed 4,976 lb. and the actual impact speed and angle were 62.3 mph and 15.0 degrees, respectively. Researchers completed standard procedures to drain fluids, take accurate measurements of the vehicle, weight, tires, and related features to prepare the vehicle for the test. Vehicles are typically painted blue to maximize the visibility of the impact outcomes in the multiple video cameras setup for each test. 4.4. Data Acquisition Systems 4.4.1. Vehicle Instrumentation and Data Processing Accelerometers, rate transducers, and speed measuring devices captured the vehicle and barrier responses during impact. Two tri-axial accelerometers mounted at the vehicle center of gravity measured the x-, y-, and z-accelerations of the vehicle. This data was used to compute the occupant ridedown acceleration and occupant impact velocities. Additionally, two tri-axial rate transducers measured vehicle roll, pitch, and yaw. Contact switches installed on the vehicle and test article synchronized time zero during the impact for the sensor data and high-speed video imagery. 4.4.2. Photographic Instrumentation and Data Processing Eight high-speed cameras are used for full-scale crash tests. One camera is placed over the impact region to capture an overhead view. Seven additional cameras are placed at different locations surrounding the impact region to capture left, right, front, rear and isometric views of the crash event. These images are downloaded immediately after the test to allow detailed scrutiny of the crash event and behavior of the barrier in slow motion, 4.5. Test Setup Conditions 4.5.1. Test Vehicle Figure 6 shows a 2014 Dodge Ram 1500 quad-cab pickup used for the crash test. Test inertial and gross static weight of the vehicle was 4,976 lb. The height to the lower and upper edge of the vehicle bumper was 14.2 in. and 26.6 in. respectively. The height to the vehicle’s center of gravity was 28 in. Researchers used the cable reverse tow and guidance system to direct the vehicle into the installation that then released the vehicle in a freewheeling and unrestrained mode just prior to impact. 4.5.2. Test Article Figure 7 shows several views of the installed SRGS prior to the test. Figure 8 shows eight views of the test vehicle in proximity to the test article to document the static interface of vehicle and the system elements. Pictures documenting the construction of the test article are available along with any related compaction, material strengths, or other features of the test article that may become relevant.

201 Figure 6. Test 3-33 Retest (Test 20004) pre-impact photos showing condition and setup of test vehicle.

202 Figure 7. Test 3-33 Retest (Test 20004) pre-impact condition views of SRGS.

203 Figure 8. Test 3-33 Retest (Test 20004) pre-impact views of test vehicle relative to SRGS.

204 5.0. CRASH TEST DOCUMENTATION 5.1. Test Designation and Impact Conditions For Test 20004 to certify that the SRGS would meet the requirements for MASH Test 3-33, the designated test vehicle needed to reach the planned speed and impact at the designated point aligned with the concrete parapet/transition along the installed system. The 2014 Dodge Ram 1500 quad-cab pickup test vehicle was accelerated down the FOIL track. It was traveling at a speed of 62.3 mph when it contacted the system at an impact angle of 15 degrees relative to the traffic face of the concrete parapet/transition as planned. Figure 9 shows the test setup for this impact. Figure 9. Test 3-33 Retest (Test 20004) impact point and angle. 5.2. Crash Test 20004 Outcome (for MASH Test 3-33 Retest) 5.2.1. General Conditions at Time of Test The test was performed on March 2, 2020, at 1:00 p.m. Weather conditions at the time of testing were as follows: • Sunny. • Wind speed and direction: NA (vehicle was traveling in a northerly direction). These were considered to have negligible effects on the outcome of the test. 5.3. Test Article and Vehicle Damage The vehicle contacted the system as shown in Figure 9, where it was captured in the system - approximately 14 ft. downstream of the side road rail from the point of impact and 7 ft. inside of the system from the traffic face of the concrete parapet/transition. Figure 10 shows the severe damage to the front of the vehicle. The impact at the nose concentrated most of the damage to the front. The front left tire lost air. There was no apparent damage to the windshield. There was no observed damage or intrusion into the passenger compartment. Figure 11 shows various views of damage to the system and Figure 12 shows various views of the vehicle and system after impact. The damage is mostly in the nose area of the system. The rail remained connected and the vehicle was restrained with more stability than in Test 19012. While an overhead view is not available, about two-thirds of the vehicle was wrapped in the rail

205 on the main road side. The impact caused the vehicle to pitch forward, but there was little roll. Several posts were bent over by the force of the impact. There was limited damage to the transition section near the end of the radius rail. The cable connectors remained functional during the impact as well. Figures 13 to 15 show various views of the crash sequence from various ground level positions outside of the system, an oblique upstream view, and from behind the system. These indicate that the system functioned effectively. Table 4 lists some of the events that occurred over the duration of the crash. Note: Based on the various views of the crash, the vehicle never lost contact with the system after first impact and came to a rest in the nose area, but well before the bridge rail end. Table 4. Events during Test 3-33 Retest (Test 20004). TIME (s) Event 0.000 Vehicle front right bumper first contacts the system. 0.090 Rail in radius section deflecting as posts lean inward, with minor change in vehicle yaw, pitch, and roll. 0.140 Vehicle moves forward deflecting rail and the maximum pitch is indicated by the height of the rear of the vehicle. 0.460 Vehicle restrained by rail wrapped around it bringing about a controlled stop. 0.910 Vehicle shows the greatest degree of pitch, but little yaw. 1.140 Rear of vehicle dropping down reversing the earlier pitch. 1.600 Vehicle comes to rest upright in the nose area with the area beyond the rear wheels still mostly outside the original rail line. Little apparent damage to far end of transition section. The main view in Figure 13 provides the best perspective on how the system functioned. Figure 14 and 15 show the limited roll, pitch, and yaw effects. None of these exceeded limits and are survivable. Figure 17 shows the measured accelerations/decelerations during the crash event. These show typical patterns of oscillation for the x-, y-, and z-axis measurements. Figure 17 shows the measured roll, pitch, and yaws for the vehicle occurring during the test.

206 Figure 10. Test 3-33 Retest (Test 20004) post-impact condition of vehicle.

207 Figure 11. Test 3-33 Retest (Test 20004) post-impact condition of SRGS.

208 Figure 12. Test 3-33 Retest (Test 20004) post-impact condition of vehicle and SRGS.

209 Figure 13. Test 3-33 Retest (Test 20004) sequential images—view of impact from right side. 0.000 s 0.230 s 1.370 s 1.600 s 0.460 s 0.690 s 0.910 s 1.140 s

210 Figure 14. Test 3-33 Retest (Test 20004) sequential images—view of impact from behind SRGS. 0.000 s 0.230 s 0.460 s 0.690 s 0.910 s 1.140 s 1.370 s 1.600 s

211 Figure 15. Test 3-33 Retest (Test 20004) sequential images—view of impact from left side. 0.000 s 0.230 s 0.460 s 0.690 s 0.910 s 1.140 s 1.370 s 1.600 s

212 Figure 16. Test 3-33 Retest (Test 20004) variations in x-, y-, and z-accelerations at CG.

213 Figure 17. Test 3-33 Retest (Test 20004) measured roll, pitch, and yaw angle plots. 5.4. MASH Evaluation The results of FOIL Test 20004 provide one step toward determining whether the SRGS meets the MASH criteria, as required to deem it acceptable for use on the highways. Table 5 provides the critical occupant risk data captured. These metrics were derived from the accelerometer, located at the vehicle center of gravity. Table 5. Occupant Risk Factors—Test 3-33 Retest (Test 20004). Occupant Risk Factor Value Time Occupant Impact Velocity (OIV) ft/s Longitudinal 24.61 0.1456 sec Lateral 6.89 0.1456 sec Occupant Ridedown Acceleration G Longitudinal -8.6 0.1555–01655 sec Lateral 6.2 0.1602–0.1702 sec Theoretical Head Impact Velocity ft/s 28.8 0.1471 sec Post Head Deceleration (PHD) G 10.5 0.1556–0.1656 sec Acceleration Severity Index (ASI) 0.65 0.0771–0.1271sec Maximum 50-ms Moving Average Longitudinal -7.0 0.0186–0.0686 sec Lateral 3.9 0.0678–0.1178 sec Vertical -3.1 0.1636–0.2136 sec Maximum Roll, Pitch, and Yaw Angle degrees Roll 6.3 0.8032 sec Pitch -11.2 0.79715sec Yaw 60.8 0.9999 sec The first column in Table 6 cites the specific MASH requirements for Test 3-33. The results column indicates the specific conclusions drawn from the test outcome. The Status column notes whether results meet the requirements. A PASS was considered appropriate in all cases.

214 Table 6. Review of MASH results for Test 3-33 Retest for FOIL Test 20004. MASH Requirement Results Status A. Test article should contain and redirect the vehicle or bring the vehicle to a controlled stop; the vehicle should not penetrate, underride, or override the installation although controlled lateral deflection of the test article is acceptable. The SRGS captured and brought the 2270P vehicle to a controlled stop. The vehicle did not penetrate, underride, or override the installation. Maximum dynamic deflection during the test was approximately 8 ft relative to the main road and 27 ft relative to the side road. Pass D. Detached elements, fragments, or other debris from the test article should not penetrate or show potential for penetrating the occupant compartment, or present an undue hazard to other traffic, pedestrians, or personnel in a work zone. Some of the posts were bent over and separated from the rail, and these and all other debris remained adjacent to the installation. These items did not penetrate or show potential for penetrating the occupant compartment. The post and other debris traveled relatively close to the ground and remained near the installation, and thereby did not present undue hazard to others in the area. Pass Deformation of, or intrusions into, the occupant compartment should not exceed limits set forth in Section 5.3 and Appendix E of MASH (roof ≤4.0 in.; windshield = ≤3.0 in.; side windows = no shattering by test article structural member; wheel/foot well/toe pan ≤9.0 in.; forward of A- pillar ≤12.0 in.; front side door area above seat ≤9.0 in.; front side door below seat ≤12.0 in.; floor pan/transmission tunnel area ≤12.0 in.). No occupant compartment deformation or intrusion occurred. Pass F. The vehicle should remain upright during and after collision. The maximum roll and pitch angles are not to exceed 75 degrees. The 2270P vehicle remained upright during and after the collision event. Maximum roll and pitch angles were 6.3 and -11.2 degrees, respectively. Pass H. Longitudinal and Lateral Occupant Impact Velocities should satisfy the following: Preferred Maximum: 30 ft/s to 40 ft/s. Longitudinal OIV was 24.61 ft/s, and lateral OIV was 6.89 ft/s. Pass I. Longitudinal and Lateral Occupant Ridedown Accelerations should satisfy the following: Preferred Maximum 15.0 G to 20.49 G. Maximum longitudinal occupant ridedown acceleration was -8.6 G, and maximum lateral occupant ridedown acceleration was 6.2 G. Pass For redirective devices, it is desirable that the vehicle be smoothly redirected and exit the barrier within the “exit box” criteria (not less than 32.8 ft), and should be documented. Also report vehicle rebound distance and velocity for crash cushions. The vehicle did not exit the installation. No significant rebound occurred. Pass

215 6.0. CONCLUSIONS AND RECOMMENDATIONS 6.1 Summary and Conclusions Test 3-33 Retest (Test 20004) was deemed successful. It showed that the system design functioned as expected in one of the most critical conditions by being able to successfully contain the large vehicle impacting the system at the nose and avoid penetrating the area behind it. It was able to do so without significant instability of the vehicle. The crucial occupant risk values were in acceptable ranges indicating that occupants would be likely to survive the crash. Parts were contained to not create other risks. Figure 18 include the summary of results from the test. 6.2 Recommendations Given the success of this test with the modification, the researcher use additional simulations and determined that it did not affect the outcome of the two previous tests, Test 3-33 (Test 19008) and Test 3-32 (Test 19010). The researcher proceed with the other remaining tests under this project as planned. 7.0. REFERENCES 1. Powers, R., Boodlal, K., Durkos, J., Boodlal, L., Marzougui, D., Kan, C. D., Opiela, K., and Tahan, F. NCHRP Research Report 1013: Roadside Barrier Designs near Bridge Rail Ends with Restricted Rights-of-Way: A Guide, Transportation Research Board, Washington, D.C., 2022. 2. FHWA FOIL. Crash Test 19008 Summary Report. Prepared by CCSA, George Mason University, Fairfax, VA, 2019. 3. American Association of State Highway and Transportation Officials (AASHTO). Manual for Assessment of Safety Hardware (MASH). AASHTO. Washington, D.C., 2016. 4. American Association of State Highway and Transportation Officials (AASHTO).. Roadside Design Guide, AASHTO. Washington, D.C., 2011. 5. American Association of State Highway and Transportation Officials (AASHTO). A Policy on Geometric Design of Highways and Streets, Washington, D.C., 2004. 6. Michie, J. D. NCHRP Report 230: Recommended Procedures for the Safety Performance Evaluation of Highway Appurtenances. TRB, National Research Council, Washington, D.C., 1981.

216 Figure 18. Test 3-33 Retest (Test 20004) summary sheet for crash test results. 0.000 s 0.460 s 0.910 s 1.600 s General Information: • Test Agency ................. Federal Outdoor Impact Laboratory • Test Number ................ 20004 • Date .............................. 03/20/2020 Test Article: • Type ............................. Short-Radius Guardrail Name or Mfg ............. Generic • Installation Length ....... 76 ft (23 m) • Key Elements .............. W-beams, Steel Posts, Cables Size/dimension .......... 31 in (787 mm) Rail Height Material ..................... W-beam rail 10 Gauge (RWM04a-b) Other ......................... 3/4 in wire rope and 5/8 in Eyebolts Test Vehicle: • Type/Designation ........ 2270P • Make and Model .......... 2014 Ram 1500 Quad Cab Pickup VIN No. .................... 1C6RR6FT8DS617391 Curb ........................... 4980 lb (2259 kg) • Test Inertial .................. 4976 lb (2257 kg) • Gross Static .................. 4976 lb (2257 kg) Soil Conditions: • Type of Soil ................. Well-graded gravel with silt & sand • Soil Strength ................ MASH Standard Soil Impact Conditions: • Speed ............................ 62.3 mph (100.3 km/hr) • Angle ............................ 15 degrees • Location/Orientation ... Vehicle centerline aligned with barrier ........................................ curved section center post Exit Conditions: • Speed ............................ Vehicle Stopped • Angle ........................... NA • Exit Box Criterion ........ NA Post-Impact Trajectory (from impact point): • Stopping Distance ........ x:13.5/y:7.3 ft (x:411.5/y:222.5 cm) • Vehicle Snagging ......... None • Vehicle Pocketing ........ Yes/Captured Occupant Risk: • Longitudinal OIV ........ 24.61 ft/s (7.5 m/s) < 39.4 ft/s (12 m/s) • Lateral OIV ................. 6.89 ft/s (-2.1 m/s) < 39.4 ft/s (12 m/s) • Longitudinal RA ......... -8.6.0 G < 20.49 G • Lateral RA ................... 6.2 G < 20.49 G • THIV ........................... 28.8 ft/s (8 m/s) 18.12 mph (29.2 km/hr) • PHD ............................ . 10.5 G Test Article Damage: . Extreme Test Article Deflections: • Permanent Set ............. NA • Dynamic ...................... NA • Vehicle Intrusion x:26.6/y:14.1 ft (8.1/4.3 m) measured from side/main road Vehicle Damage: • VDS .............................. 12FD3 • CDC.............................. 12FDEW2 • Max. Deformation Exterior ................... 18.3 in (46.5 cm) Windshield .............. 0.2 in (0.5 cm) Occupant Comp. ..... 0.3 in (0.8 cm) Vehicle Post-Impact Behavior: • Vehicle Stability .......... Satisfactory • Max. Roll Angle .......... 6.3 degrees • Max. Pitch Angle ........ -11.2 degrees • Max. Yaw Angle ......... 60.8 degrees Overall Performance: Pass 15°