A hypoplastic model for crushable sand under a wide range of stress levels

Depending on the characteristics of soil particles and external load, natural soils often undergo particle breakage which may significantly influence their mechanical behavior. In this study, a hypoplastic model is proposed to describe the sand behavior over a wide range of stress levels, especially those sufficient to cause particle breakage. The characterized void ratios and granulate hardness of the model are related to the plastic work to reflect the impact of particle breakage on the strength and deformation properties of sand. The influence of confining pressure on the extent of particle breakage is properly considered. The model is demonstrated to be capable of simulating the response of crushable sand under various test conditions. The simulation results of the original hypoplastic model are also presented, which indicates that neglecting the particle breakage may cause unreasonable predictions at high stress state.