Description of critical state for sands considering particle crushing

In recent years, granular soil is widely used in more and more earth-rockfill dams and high-filled projects being built. However, particle crushing of granular soil can not be ignored as the particle crushing of granular soil under high stress is very common. In order to describe the behaviours of sands, some researches are completed as follows. Firstly, by analyzing the experimental results, some breaking characteristics of sands are discovered under the applied pressure stress and shear stress. Secondly, based on the UH model, a constitutive model for sands is proposed by introducing three new parameters of particle crushing which are about pressure stress and shear stress respectively. The proposed model is capable of describing the characteristics of sands, such as stress-strain relationships, shear dilatancy, strain-hardening and softening. In addition, the characteristics, that different compression curves will eventually arrive together under high stress and the critical state line will move down under shear stress, can also be reflected by the model. Finally, by comparing the predicted results of the model and the test results of Lade's, it is proved that the proposed model can describe the behaviours of sands well.