Through analyzing the present rheological models and experimenting lots of creeping tests of frozen clay specimens under uniaxial stress states

the results show that the nonlinear N element substitute for the linear one is feasible and the Xiyuan model is improved. Making use of the Mises yield criterion

a soft matrix is derived to use numerical calculating as a viscous-elastic-plastic material. Numerical simulation of the shaft well excavation process and field measurements of the deformation of deep soil frozen wall in Huainan Mine show that the improved Nishihara model is feasible for FEM numerical simulation of deep soil frozen wall.