Comparison between Cam-Clay and Tij-Clay Elastoplastic Models for the Simulation of the Mechanical Behavior of Clays

摘要

Cam-clay model can reproduce reasonably well the mechanical behavior of soils. The development of this model, however, was based exclusively on conventional axi-symmetric triaxial tests, what constitutes its main drawback. Nevertheless, several authors have proposed to extend it to three-dimensional situations. To overcome that limitation, Nakai and Matsuoka proposed the Tij-clay model, based, mainly, on the Spatially Mobilized Plane and on the modified stress tensor Tij. One important discovery related with the SMP was the linear relationship between shear-normal stress ratio and shear-normal strain increment ratio. The influence of stress path on soil deformability is properly taken into account by dividing the plastic strain increments into two parts. The capacities of the two models in representing the soil behavior are studied through comparisons between true triaxial tests and numerical simulations results. It is verified that the Tij-clay model is better than Cam-clay, mainly when the stress path leaves the triaxial plane.