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59 For the Test 2 configuration, the selected width corre- sponded to the first inflection point on the preliminary fail- ure curve established for the 45-degree asperity angle (see Figure 66). The depth for this test could have been selected to bisect the region of "marginal/unknown" performance. However, this would have involved testing asperities at a depth of approximately 6 mm, which was considered to be some- what meaningless for a realistic aesthetic surface treatment and would not yield any significant information for adjusting the surrogate OCD thresholds. Hence, the depth for this test was selected to verify the failure line established by the pre- liminary guidelines. CRASH TEST 1 (474630-1) Figure 68. Barrier damage for Crash Test 1. The New Jersey concrete safety shape barrier evaluated in the first test had asperities that were 559 mm wide and 25 mm deep. The asperity inclination angle was 45 degrees, and the 13 mm deep. The asperity inclination angle was 45 degrees, asperity spacing was 25 mm. A photograph of the barrier before and the asperity spacing was 25 mm. A photograph of the bar- the test is shown in Figure 67. rier before the test is shown in Figure 69. The barrier was impacted by a 2,057-kg pickup truck at an The barrier was impacted by a 2,112-kg pickup truck at an angle of 26.5 degrees and an initial speed of 99.8 km/h. The angle of 24.9 degrees and an initial speed of 99.3 km/h. The barrier contained and redirected the pickup truck. The vehi- barrier contained and redirected the pickup truck. The vehi- cle did not penetrate, underride, or override the installation. cle did not penetrate, underride, or override the installation. The vehicle remained upright during and after the collision The vehicle remained upright during and after the collision period. The longitudinal occupant impact velocity and ride- period. The longitudinal occupant impact velocity and down accelerations were within acceptable limits of the ridedown accelerations were within acceptable limits of the NCHRP Report 350 requirements. Maximum OCD was NCHRP Report 350 requirements. Maximum OCD was 139 mm laterally across the cab from kick panel to kick panel. 216 mm in the left firewall area, and the floor pan was sepa- In the immediate area of impact, three of the "ribs" between rated at the seam between the firewall and the toe pan from asperities were sheared off and the face of the barrier was the left side across the transmission tunnel. gouged (see Figure 68). The crash test met the evaluation cri- Some of the ribs between asperities were partially sheared teria presented in NCHRP Report 350. off from the surface of the concrete barrier, while others re- mained attached and received scrapes and gouges (see Fig- CRASH TEST 2 (474630-2) ure 70). The crash test did not meet the evaluation criteria presented in NCHRP Report 350 due to excessive OCD. The The New Jersey concrete safety shape barrier evaluated FHWA guidelines define failure to be a value significantly in the second test had asperities that were 178 mm wide and greater than 150 mm. Figure 67. Setup for Crash Test 1. Figure 69. Setup for Crash Test 2.