Numerical analysis of geocell-reinforced retaining structures

Abstract

This paper presents numerical analysis on the behavior of geocell-reinforced retaining structures with various layouts. The constitutive model adopted for materials consisted of a nonlinear elastic stress–strain relationship with Mohr–Coulomb yield criterion. The strength parameters of the materials were obtained from relevant tests. For verification of the numerical model, three model-scale gravity-type walls with different facing angles were analyzed, and the finite difference program FLAC was utilized in the analysis. The results of the verification show good agreement in predicting the potential slip surface as well as estimating the critical load causing the wall to fail. The verified numerical model was then employed to study various layouts of retaining structures, which were constructed with the same amount of geocells, to compare the failure mode as well as the deformation of the structure. It has been found, irrespective of gravity type or facing type, the structure that extends the length of geocells in some layers to serve as reinforcement performs well in reducing the deformation of the structure and decreasing the potential slip zone. Moreover, with lengthening geocell layers as reinforcements, extended facing-type structures of various facing angles were analyzed. The results show that a wall with a facing angle less than 80° will significantly reduce the lateral displacement of the wall face. Further, the lateral earth pressures against the back of wall facing are somewhat higher than the horizontal stress in Rankine's active state, while those along the back of the reinforced zone are in at-rest state.