Numerical Modeling of Three-Tiered Reinforced Soil Wall with Different Offset Distances Subjected to Dynamic Excitation

Reinforced retaining wall using geogrids is an effective method to deal with high and steep soil slope under complicated geological engineering conditions. There have been comparatively lesser studies on multi-tiered walls due to its limited application. This paper aims at making a comparative study of the behavior of three-tiered reinforced soil wall with small and large offset distances subjected to seismic excitations. A 2.8 m high numerical model of reinforced soil wall is developed using finite element software PLAXIS 2D. The numerical model is subjected to dynamic excitations of 0.4 g Kobe earthquake and results of the response of the numerical model are validated with shake table tests results of Ling et al. [7]. A 9 m high three-tiered wall with small offset distances (i.e., 0.5 m and 0.75 m) and large offset distances (1.5 m and 2.5 m) is simulated with validated model parameters. The tiered walls are subjected to seismic excitations of the Kobe earthquake at a peak acceleration of 0.4 g and the variation of lateral pressure, maximum reinforcement loads, and acceleration amplification factors of three-tiered walls with various offset distances are compared. The results showed that the lateral stress, maximum reinforcement load, and acceleration amplification factor decreases with the increasing tier offset.