Nonlinear analysis of unsaturated soils using a meshfree method

A fully coupled algorithm based on a recently developed meshfree method, called smoothed point interpolation method, is introduced for hydro-mechanical analysis of unsaturated porous media considering hydraulic hysteresis and material nonlinearity. A simple node selection scheme is adopted which ensures the non-singularity of the moment matrix in constructing the polynomial point interpolation shape functions. An effective stress based framework based on the work of Khalili et al. (2008) is followed in this study, and a hysteretic water retention model is taken into account which enables the evolution of water retention curve (WRC) with volumetric changes (Pasha et al., 2017). An elastoplastic constitutive model is employed within the context of bounding surface plasticity theory for predicting the nonlinear behavior of soil skeleton in unsaturated porous media. The applicability of the model is verified through several numerical examples.