EVALUATION OF FAILURE IN SOILS UNDER UNCONFINED COMPRESSION USING 3-D RIGID PLASTIC FINITE ELEMENT ANALYSIS

Abstract

Authors have visualized a failure in the soil under unconfined compression using X-ray CT scanner and the shape of failure zone has been reconstructed in three dimension. The purpose of this paper is to analyze the failure of the soils under unconfined compression using rigid plastic finite element method(RPFEM) in three dimension. First of all, the 3-D RPFEM was formulated and the verification of this method was examined by comparing with the solution on plain strain problem. Then, a series of numerical analysis was conducted using developed 3-D FEM program for unconfined compression test of mixed soil which is made of dredged slurry with cement and air foams. Here, the results of CT scanning which is the density distribution in the specimen were used in order to perform the non-homogeneity of the soil. In this study, not only the strength of this soil specimen but also the shape of failure zone are compared between the results of numerical analyses and those of unconfined compression tests. Finally, the failure of soils was able to be well evaluated and thus the effectiveness of this analysis was confirmed.