Behavior of braced wall embedded in saturated liquefiable sand under seismic loading

Abstract

It is well known that the generation of excess pore water pressure and/or liquefaction in foundation soils during an earthquake often cause structural failures. This paper describes the behavior of a small-scale braced wall embedded in saturated liquefiable sand under dynamic condition. Shake table tests are performed in the laboratory on embedded retaining walls with single bracing. The tests are conducted for different excavation depths and base motions. The influences of the peak magnitude of the ground motions and the excavation depth on the axial forces in the bracing, the lateral displacement and the bending moments in the braced walls are studied. The shake table tests are simulated numerically using FLAC 2D and the results are compared with the corresponding experimental results. The pore water pressures developed in the soil are found to influence the behavior of the braced wall structures during a dynamic event. It is found that the excess pore water pressure development in the soil below the excavation is higher compared to the soil beside the walls. Thus, the soil below the excavation level is more susceptible to the liquefaction compared to the soil beside the walls.