ABSTRACT
Back-to-back mechanically stabilized earth (MSE) walls are commonly used for ramp ways and bridge approaches. The behavior of back-to-back MSE walls is significantly influenced by the geometric configuration, especially the horizontal distance (i.e., width-to-height ratio) of the wall. This paper presents a numerical study on the behavior of back-to-back MSE walls to investigate the influence of horizontal distance on the interaction. Numerical simulations were conducted with different width-to-height ratios. Results indicate the horizontal distance has significant influences on the static behavior of back-to-back MSE walls. The lateral soil thrust behind the reinforced soil zone, the required reinforcement strength, and the vertical toe load generally increase with increasing horizontal distance up to a critical value. The Federal Highway Administration (FHWA) simplified method significantly overestimates the required reinforcement tensile strength, but underestimates the lateral soil thrust for the range of horizontal distances involving interaction between the back-to-back MSE walls.
