Numerical Study on Effects of the Number of Reinforcement Layers for Reinforced-Sand Retaining Wall

In order to investigate effects of the number of reinforcement layers on the deformation and failure of reinforced-sand retaining walls, results from plane strain laboratory model tests are simulated by a nonlinear FEM analyses incorporating an elasto-plastic constitutive for sand. The constitutive model takes into account the effects of the following factors for sand: (a) pre-peak work-hardening and post-peak work-softening; (b) effects of stress history and stress path; (c) the confining pressure dependency and strength anisotropy; (d) the stress-dilatancy characteristics; and (e) strain localization into a shear band(s). The results indicate that load-settlement relationships obtained by the FEM analyses generally agree well with those from the physical experiments. It is found that the peak footing load increases significantly with the increase of the number of reinforcement layers, despite the total tensile stiffness of all the reinforcements in each model remains the same. In addition, the results also indicate that the progressive failure of reinforced-sand retaining walls with a development of shear bands is reasonably simulated by the proposed FEM analyses, and the effects of the reinforcement layers can be well understood.