It is an important method for slope stability analysis by using the numerical results of limit equilibrium analysis

and how to determine the location of the most dangerous slip surface is the key for the slope stability analysis.This paper introduces a method

which controls the endpoints of slip surface by using particle swarm optimization theory

and controls the surface radius by equipartition approximation method.The method can be used to search the potential slip surface inside a slope and to calculate the safety factor of slip surface

and then the minimum safety factor of the slope and the most dangerous potential slip surface position are determined.Using a landslide of Kunming highway as an example for analysis

comparing the most dangerous sliding surface search with field survey results

the results show that the calculation result is consistent with the practical engineering.Therefore

the validity of this method is confirmed.