Geosynthetics and Soil Interaction Numerical Modeling for High-speed Rail Lines Substructure

Abstract

The purpose of this study is to propose an approach to modeling a geogrid in both not confined and сconfined by soil conditions. This is achieved in two stages. First of all, the numerical model is verified by the test results, and then it is used to study the detailed behavior of the geogrid in the soil massive. A nonlinear FEM analysis was carried out to simulate the behavior of a geogrid under tensile load. The model used in the FEM analysis is capable of covering the ranges of elastic and plastic area of the stress—strain relationship under tensile loading. The geogrid geometry is modeled with its detailed characteristics, including the thickness of the ribs. The models presented in this study were performed by using Plaxis finite element software. Experimental results show that the geogrid sample behaves like a nonlinear elastoplastic material. Therefore, the model simplifying using linear elasticity may lead to an incorrect result. A practical constitutive model is needed that can describe both the nonlinearity of the material and the plasticity.