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From page 159... ... 159 7 TL-5 FULL-SCALE TEST ON TOP OF A 10-FT HIGH MSE WALL A TL-5 full-scale crash test was performed to validate the preliminary design guidelines and/or modify them as necessary. Prior to the test, an FE analysis was performed using LS-DYNA to help plan and predict the outcome of the TL-5 crash test. Read the entire page →
From page 160... ... 160 7.1.1 Calculation of MSE Wall Capacity The force expected in the 10 ft (3.05 m) long reinforcement strips due to the gravity load was computed according to AASHTO LRFD (3) Read the entire page →
From page 161... ... 161 Finish Grade 1'-3" 512" 112" 1014" 6'-10" 1134"2" 3'-6" 3"10" 2'-5" 158" #4 Long. Rebars Below Grade Bar 5A #5 @8" Bar 4C #4 @8" 712" Bar 4A #4 @8" Bar 4A #4 @8" 3'-4" #7 Long. Read the entire page →
From page 162... ... 162 Figure 7-2 TL-5 BMS system model of the TL-5 test installation. Figure 7-3 System reaction force of the TL-5 MSE wall test installation model. Read the entire page →
From page 163... ... 163 Figure 7-4 Downstream view of the TL-5 MSE wall model. Read the entire page →
From page 164... ... 164 a) Three-dimensional view of the test installation model (pre-impact time) Read the entire page →
From page 165... ... 165 associated with the impacts of both the tractor and the trailer. To enable comparison of forces and displacements, the barriers and selected strips locations were assigned an alphanumeric designator that describes their horizontal and vertical position in the wall as shown in Figure 7-6. Read the entire page →
From page 166... ... 166 a) Pre-impact time position b) Read the entire page →
From page 167... ... 167 Figure 7-8 50 msec. average impact load on the NJ barrier. Read the entire page →
From page 168... ... 168 The displacement–time history is shown in Figure 7-10. The maximum dynamic displacements at the top and bottom of the 42-in. Read the entire page →
From page 169... ... 169 second layer, the maximum total load and dynamic impact load occurred in strip section B3-E-2nd and was 3.46 kips (15.4 kN) and 1.91 kips (8.5 kN) Read the entire page →
From page 170... ... 170 a) Total load b) Read the entire page →
From page 171... ... 171 Figure 7-13 Displacement in the reinforcing strips from the FE model. 7.2.3 Panels Analyses The damage mapping and the bending moment in the wall panels below the IP was evaluated from the FE model, as shown in Figure 7-14 and Figure 7-15. Read the entire page →
From page 172... ... 172 Figure 7-14 Damage profile of the test wall panel at B3 (below IP) for TL-5-1 impact on a NJ barrier on top of the MSE Wall. Read the entire page →
From page 173... ... 173 a) Dynamic displacement b) Read the entire page →
From page 174... ... 174 7.3.1 TL-5 MSE Wall Construction and Test Installation An overall layout of the TL-5 MSE wall test installation is shown in Figure 7-17 through Figure 7-19. The total length of the installation is about 135.5 ft (41.3 m) Read the entire page →
From page 175... ... 175 Figure 7-17 Overall layout of the TL-5 MSE wall test installation. Read the entire page →
From page 176... ... 176 a) South section (SEC. Read the entire page →
From page 177... ... 177 a) Three-dimensional view of the installation b) Read the entire page →
From page 178... ... 178 mm) wide at the top, and 23.9 in. Read the entire page →
From page 179... ... 179 The sand backfill and the road base satisfied the gradation limits of TxDOT Type B (Table 7-2 (48) Read the entire page →
From page 180... ... 180 Table 7-3 Select index properties of the backfill soil material (46) Property Soil Sample Clean Sand Road Base D10(1) Read the entire page →
From page 181... ... 181 a) Clean sand (SP) Read the entire page →
From page 182... ... 182 a) Clean sand (SP) Read the entire page →
From page 183... ... 183 in-situ dry density and the water content as compacted were measured using a nuclear density (ND) device. Read the entire page →
From page 184... ... 184 The friction angle of the sand was measured in a direct shear test by recompacting the sand at its maximum dry density; a value of 40 degrees was obtained together with an apparent cohesion of 0.73 psi (5 kPa) Read the entire page →
From page 185... ... 185 Figure 7-24 Selected strips with strain gage location for the TL-5 test wall. Displacement and/or rotation of the barrier and wall panels were determined using highspeed video operating at 1000 frames/second. Read the entire page →
From page 186... ... 186 the test installation using a cable reverse tow and guidance system, and was released to be freewheeling and unrestrained just prior to impact. Read the entire page →
From page 187... ... 187 7.3.5 Test Description The 36000V vehicle, traveling at an impact speed of 49.4 mph (79.5 km/hr.) , impacted the NJ shape barrier placed on top of the MSE wall 37 ft (11.28 m) Read the entire page →
From page 188... ... 188 a) NJ shape barrier after test b) Read the entire page →
From page 189... ... 189 Figure 7-27 Damage to traffic face of TL-5 MSEW after the impact test. Read the entire page →
From page 190... ... 190 Figure 7-28 Field side of TL-5 MSEW after test. Read the entire page →
From page 191... ... 191 Figure 7-29 Crack in soil after impact a) Front view of the tractor b) Read the entire page →
From page 192... ... 192 7.3.8 Occupant Risk Occupant risk values are not applicable for MASH test 5-12. However, data from the accelerometers, located at the vehicle mid-position, were digitized for evaluation of occupant risk. Read the entire page →
From page 193... ... 193 0.00 sec. Read the entire page →
From page 194... ... 194 a) x-acceleration (front of the tractor) Read the entire page →
From page 195... ... 195 a) x-acceleration (close to the rear tandem axles of tractor) Read the entire page →
From page 196... ... 196 Figure 7-34 Roll, Pitch and yaw angle measure close to the vehicle fifth wheel. Read the entire page →
From page 197... ... 197 Using the mass of the vehicle and the lateral acceleration measured at the central axles of the tractor-van-trailer and at the rear tandem axles of the trailer, the impact force can be approximated using Newton's second law of motion, as described in section 3. The results show that the second and third peak load were approximately 140.8 kips (626.6 kN) Read the entire page →
From page 198... ... 198 a) acceleration time-history b) Read the entire page →
From page 199... ... 199 Figure 7-37 Location of displacement bars affixed on the barrier and panels. Figure 7-38 Location indicators for strain gages on the strips. Read the entire page →
From page 200... ... 200 Table 7-5 Measured dynamic loads on the soil reinforcing strips Strip Section Layer of soil reinforcement Location from the panel face (in) Maximum load from raw data (kips) Read the entire page →
From page 201... ... 201 a) Strip section B3-E b) Read the entire page →
From page 202... ... 202 a) Strip section B3-E b) Read the entire page →
From page 203... ... 203 Table 7-6 Static load on the soil reinforcing strips Static Load measured (kips) Static Load calculated by AASHTO (kips) Read the entire page →
From page 204... ... 204 a) Measured Dynamic load b) Read the entire page →
From page 205... ... 205 Figure 7-42 Hairline crack in the panels after impact. In the full-panel section below barrier 3 (panel column C-8) Read the entire page →
From page 206... ... 206 Figure 7-43 Sketch of free body diagram of the load transferred into the wall panels. 7.3.13 Other Instrumentation Reflective targets were placed at different locations on the barriers (B2, B3, B4, and B5) Read the entire page →
From page 207... ... 207 Figure 7-44 Reflective targets in the barrier and wall panel to measure permanent deflection. Read the entire page →
From page 208... ... 208 Figure 7-45 Location of the reflective displacement targets for measurement of permanent deflection. Read the entire page →
From page 209... ... 209 Table 7-8 Results of permanent deflection measurements. Permanent Displacement Measurement with Total Station Target Point Δx (in.) Read the entire page →
From page 210... ... 210 Figure 7-46 Lateral permanent deflection at the selected targets. B-2 B-3 B-4 B-5 C-6 C-7 C-8 C-9 C-10 C-11 C-12 C-13 C-14 Note: Displacement in inches 0.67 0.57 0.53 1.17 0.89 0.65 0.42 0.04 1.06 0.74 0.39 0.93 0.61 0.41 0.67 0.56 0.44 0.53 0.40 0.24 0.43 0.31 0.16 0.12 0.12 0.12 0.39 0.14 0.09 0.54 0.07 0.41 0.17 0.16 0.43 0.09 0.47 0.13 0.12 0.32 0.04 0.24 0.16 0.10 0.19 0.03 0.12 0.04 0.03 0.19 0.01 0.14 0.10 0.02 0.15 0.02 0.08 0.03 0.03 1'-238" 3'-778" 6'-1" 10' 7'-6" 3'-6" 3'-4" 7'-6" 1.03 0.67 0.39 IMPACT POINT Read the entire page →
From page 211... ... 211 Figure 7-47 Total permanent deflection at the selected targets. IMPACT POINT B-2 B-3 B-4 B-5 C-6 C-7 C-8 C-9 C-10 C-11 C-12 C-13 C-14 Note: Displacement in inches 0.70 0.62 0.58 1.22 0.97 0.76 0.57 0.27 1.12 0.85 0.66 1.0 0.74 0.58 0.73 0.64 0.53 0.60 0.50 0.38 0.50 0.40 0.31 0.19 0.18 0.18 0.54 0.27 0.31 0.63 0.27 0.54 0.39 0.39 0.54 0.24 0.54 0.30 0.26 0.44 0.21 0.40 0.33 0.30 0.34 0.19 0.30 0.19 0.18 0.30 0.17 0.26 0.25 0.22 0.25 0.13 0.16 0.16 0.12 1'-238" 3'-778" 6'-1" 10' 7'-6" 3'-6" 3'-4" 7'-6" 1.10 0.79 0.58 Read the entire page →
From page 212... ... 212 a) Top of the barriers b) Read the entire page →
From page 213... ... 213 Figure 7-49 Structural integrity of the moment slab after impact. 7.4 Conclusions The TL-5 barrier mounted on top of the MSE wall performed acceptably according to the evaluation criteria specified for MASH test 5-12 as summarized in Table 7-9. Read the entire page →
From page 214... ... 214 Table 7-9 Performance evaluation summary for MASH Test 5-12 on the MSE Wall. Test Agency: Texas Transportation Institute Test No.: 478130 Test Date: 2012-09-26 MASH Evaluation Criteria Test Results Assessment Structural Adequacy A Read the entire page →
From page 215... ... 215 a) Full-scale MSE wall and vehicle set-up b) Read the entire page →
From page 216... ... 216 significantly affect the results since the coping of the barrier did not contact the wall panels during the full-scale crash test (as indicated by the tape switch installed on the wall panel) Read the entire page →
From page 217... ... 217 c) Initial impact (t=0 sec.) Read the entire page →
From page 219... ... 219 a) X-direction b) Read the entire page →
From page 220... ... 220 a) X-direction b) Read the entire page →
From page 221... ... 221 a) AX direction b) Read the entire page →
From page 222... ... 222 Table 7-10 Comparisons between measured and simulated displacement in the barriers Barrier 3 (IP) Barrier 4 (Joint) Read the entire page →
From page 223... ... 223 The dynamic displacements of the wall panels during the test could not be measured due to problems in the instrumentation. The lateral permanent deflection, measured using a total station, ranged from 0.01 in. Read the entire page →
From page 224... ... 224 a) Strip section B3-E b) Read the entire page →
From page 225... ... 225 a) Strip section B4-H a) Read the entire page →

From page 159...

... 159 7 TL-5 FULL-SCALE TEST ON TOP OF A 10-FT HIGH MSE WALL A TL-5 full-scale crash test was performed to validate the preliminary design guidelines and/or modify them as necessary. Prior to the test, an FE analysis was performed using LS-DYNA to help plan and predict the outcome of the TL-5 crash test.