Energy Approach towards Stress-dilatancy Formulation Based on Double Slip-rotation Rate Concept
نویسندگان
چکیده
This paper proposes a new approach for the analysis of shear-induced volume change of granular materials. Following a revisit to the micro-mechanical deformation mechanism and the ˆndings from discrete element method simulations, it is concluded that the double slip-rotation rate mechanism is appropriate for the description of granular materials subjected to shear. The implementation of energy principle with the double slip-rotation rate mechanism provides a new method for the derivation of stress-dilatancy relation under general stress conditions without adopting Rowe's hypothesis of minimum energy ratio. This new approach can be easily extended to take into account the non-coaxility of granular material deformation. The dilatancy formulations proposed by Taylor, Rowe and Matsuoka-Nakai can all be recovered as special cases of the proposed approach. Comparisons with experimental data show that the new stressdilatancy relation correctly captures the dilatancy behaviour of sand observed in both general 3D stress conditions and simple shear tests.
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