To describe nonlinear shear rheological properties and establish shear rheological model for soft clay

the shear creep experiential formula suggested by Singh-Mitchell was modified to be valid in low corrected stress level condition. The functional expression of viscoplastic shear strain rate in terms of shear stress and viscoplastic shear strain was derived from the relationship equation among viscoplastic shear strain

dissipative shear stress and equivalent time. After combining this expression with shear elastic model

a shear elasto-viscoplastic model was formulated. Based on this model

analytical solutions of shear rheology were not only obtained for single-stage and multi-stage loading under constant effective confining stress

but integral solution of shear rheology was also obtained for both effective confining and shear stresses to vary with time. The results show that the rheological model can numerically simulate relatively well the shear creep development under multi-stages loading in drained triaxial test

and describe the rheological rules that shear strain changes with effect factors such as corrected stress level (or shear stress)

effective confining stress and loading duration.