A non-linear interface model for monotonic shear coupling in granular soil–structure interaction problems

Abstract

The accurate prediction of the behaviour of soil–structure interfaces that accounts for shear coupling is of concern in the design and analysis of soil–structure interaction problems. In this study, an interface constitutive model capable of simulating the non-linear behaviour of granular soil–structure interface systems under three-dimensional loading conditions is proposed. The proposed constitutive model is a state-dependent elasto-plastic model, and it is formulated in the framework of two-surface plasticity and critical state soil mechanics. The interface model considers the effect of shear coupling and is capable of predicting the monotonic behaviour of soil–structure interfaces over a wide range of normal and shear stresses, and under different stress paths using a single set of model parameters. It also captures other complex behaviour characteristics such as strain hardening and softening, volumetric compaction and dilation, and phase transformation responses of granular soil–structure interfaces under orthogonal shear application. The performance of the proposed constitutive model is evaluated by comparing its predictions for both gravelly and sandy soil–structure interfaces with available experimental results.