In connection with slope stability of soil nailing support for foundation pit
the authors discuss the shortcomings of limit equilibrium method and indicate that the FEM stability analysis is new trend to evaluate the stability of foundation pit. The slip surface stress analysis method and strength reducion method are used to analyze the stability of soil nailing support for foundation pit. For the slope without supporting foundation pit
the results of safety factor and critical slip surface obtained by two finite element methods are consistent and the shapes of critical slip surface keep sameness with the reduction of strength parameters with soil. For the slope with soil nailing support for foundation pit
the safety factors by two finite element methods are consistent; but the shapes of critical slip surface are inconsistent in different stages. The reason is that only the strength of the soil and the cement deep mixing pile are reduced during the process in the calculation; and the strength parameters of the nail bar are regarded as constant. Finally
the authors indicate whether or not considering the reduction of soil in strength reducion method with FEM waits for further research.