Crash Wall Design for Mechanically Stabilized Earth (MSE) Retaining Wall Phase I: Engineering Analysis and Simulation (405160-15)

Vehicular traffic may exist on either the high (fill) side of the Mechanically Stabilized Earth (MSE) retaining wall, on the low side, or both sides. For traffic on the high side, a conventional traffic barrier might be placed on or near the top of the wall and mounted on a moment slab or a bridge deck. For traffic on the low side, a conventional traffic barrier might be installed adjacent to the wall or the wall itself may serve as the traffic barrier. Typical MSE wall panels are not designed to resist vehicle impacts. Hence, structural damage to the wall panels and the earth fill would require complicated and expensive repairs. A simple reinforced concrete crash wall constructed in front of the MSE wall panels can significantly reduce damage to wall panels. It may prove practical to implement such a design in order to reduce costly repair to the MSE wall structure. In this project, the research teal reviewed, modeled, and analyzed a typical crash wall design to determine its effectiveness using Test Level 4 impact conditions of the crash testing guidelines (Manual for Assessing Safety Hardware). Three MSE wall finite element models have been developed: (1) a typical section of an MSE wall excluding the crash wall to observe damage of the panels impacted directly, (2) an MSE wall with a crash wall to quantify reduction in damage of the panels, and (3) an MSE wall with a crush wall and anchors to provide positive interaction between the wall panels and the crash wall. Based on these three simulations, a 0.2 m (8 inch) thick crash wall is considered adequately designed to reduce damage to the MSE wall.