Effect of Mesh Size on Soil-Structure Interaction in Finite Element Analysis

Abstract

Numerous consitutive models have been developed over the past years for modelling the stress-strain behaviour of soils, using finite element and/or finite difference calculations of soil structures and soil/structure interaction problems under axisymetric, plane strain, and/or general three dimensional conditions. Selection of the appropriate parameters and soil model can have a significant impact on the results of numerical analysis. In this study, the interaction of soil and reinforced cement concrete raft foundation in a sandy soil at a depth of 9m below the existing ground level is analysed by using with both analytical and finite element analysis (FEM). Analytical calculations were done using method available in literature and a finite element analysis was carried out using the hardening soil model available in PLAXIS 2D (2020, connect version). The results obtained from analytical calculations were compared with those obtained from the Hardening Soil (HS) Model. In the model sizes of mesh were changed and there effect on interaction behaviour is observed by studying the strength and deformation results obtained from FEM analysis. It was observed that very fine mesh size gave more accurate results compared to the other sizes.