DETERMINATION OF SLIP SURFACE IN SLOPE BASED ON THEORY OF SLIP LINE FIELD

A method to search for the slip surface in slope through finite element result based on the theory of slip line is improved;and the influence of the flow rule on the slope stability is studied based on this method. In this method,the elastic area and plastic zone can be distinguished and the different flow rules can be considered. The methods to protract the orientation field of slip line and trace the slip line from any point in export portion are brought out. The slip line of which the safety factor is least,is the critical slip surface. The examples have shown the reliability of the method. The study indicates that the flow rule has small influence on the stability of the slope without restriction;however,the critical slip surface may be different. If there are loads on the top of the slope, especially the loads are crucialt,he flow rule can influence both the safety factor and the slip surface remarkably. If the associated flow rule is adopted,the stability of the slope may be overestimated.