Elastoplastic Modelling of Hydraulic and Mechanical Behaviour of Unsaturated Expansive Soils

The Barcelona Expansive Model (BExM) for unsaturated expansive soils is complicated and the micro parameters and the coupling function from micro-structural strain to macro-structural strain are difficult to be determined. This paper presents an elastoplastic constitutive model from the macroscopic observation for predicting the hydraulic and mechanical behaviour of unsaturated expansive soils. The model predictions are performed on the results of triaxial tests on compacted unsaturated expansive clay available in the literature. The comparisons between measured and predicted results indicate that the model offers great potential for quantitatively predicting the hydraulic and mechanical behaviour of unsaturated expansive soils.