Cyclic shearing behavior of K0-consolidated clay and its rheological simulation

Experimental researches are conducted on natural Wenzhou clay to study its undrained cyclic deformation, pore pressure behavior and effects of loading frequency. Taking the stress-induced anisotropy into account, all the specimens are initially restored to the in-situ stress state under K0 consolidation. The emergence of the inflexion points on the accumulative strain curves can be considered as a suitable failure criteron for K0-consolidated clay and the corresponding peak strains es,tp of all the tests are about 3%. For a given dynamic stress ratio, the stress duration t is a key factor which comprehensively reflects the effects of loading frequency and cyclic number. Finally, based on the similarity, the accumulation during undrained cyclic shearing is equivalent to a static creep process, and a proposed anisotropic elastic visco-plastic constitutive model is used for the simulation. The predicted results indicate that the creep equivalent simplification is suitable in practice, and that the accumulation behavior of natural clays can be fairly predicted.