Compared with the strain definitions of finite deformation, the defects of Green strain and polar decomposition theorem have been pointed out. Based on the additive decomposition theorem, which was established by Prof. Chen Zhida, the nonlinear gauge method being fit for the numerical simulation is presented. This method combines the Ritz-Galerkin approximate method together with visualization and is a new extension of residual method. The numerical example demonstrate that this method can obtain the results approach to practical phenomena and is an effective and feasible approach to solve the large deformation of mining subsidence.