Evaluation of shallow foundation settlements by an elasto-plastic kinematic-isotropic hardening numerical model for granular soil

A numerical model based on a recent non-associative elasto-plastic model for sands (the Severn--Trent model), implemented in an FEM code, is presented. This model, which simultaneously takes into account the effects of the relative density DR and the mean effective stress level p reproduces the stress--strain behaviour of granular materials with reasonable accuracy. The constitutive relations are arranged in the form of a forward stress integration algorithm in a new subroutine. The algorithm is validated by comparison with the experimental results of several triaxial tests; the computed and experimental results are generally in good agreement for both loose and dense sands. Finally, the settlement of full-scale shallow foundations resting on a sand deposit is analysed; the numerical results obtained are very close to the experimental data.