Abstract: When calculating slope stability under anchorage force by limit equilibrium method, anchorage force is usually treated as a concentrated force, and the distribution curves of normal stress on slip surface and inter-slice forces are very unreasonable. In addition, if the effect of anchorage force is treated by conventional method and the stability of anchored slope is analyzed by critical sliding field method, the sliding surface searched will change abruptly. In order to overcome the above inherent defects, the elastic solution of semi-infinite body subjected to normal force is approximated as the equivalent model of additional stress generated by anchoring force in slope body. On this basis, the calculation method of critical sliding field of slope under anchoring force is established. The analysis of examples shows that the approximate equivalent treatment method of concentrated force is reasonable, which further enriches the stability analysis method of anchored slope. The method has also successfully applied to evaluate the stability of a practical complex slope engineering. The results show that the anchorage force can change the location of the potential slip surface. The proposed approach can search the real potential slip surface with reasonable distribution of normal stresses and inter-slice forces under the action of anchorage force and the corresponding safety factor is more reliable. Meanwhile, the method can comprehensively evaluate the overall and local stability of the slope, and provide the spatial distribution of the unstable region for the actual slope engineering, so as to effectively control it.

Key words: slope engineering, anchorage force, stability