Abstract: The degrees of freedom of the slip surfaces of slopes, when generated using elementary functions, are reduced greatly and the surface smoothness can be guaranteed. Based on the existing theories, this paper presents a new general method for constructing slip surfaces using different base functions and achieving a unified framework for the generation. We transform the geometric problems involved in slip surface generation to determining the parameters of base functions in algebra, and recommend how to solve the constraint condition of the coefficients. Five base functions are suggested and are used in a classical example for slope stability analysis. Safety factors and instability acceleration are calculated using Morgenstern-Price method. Results show the base functions recommended by the authors meet the requirements and can even generate some special slip surfaces that cannot be achieved by traditional methods.

Key words: slip surface, slope, elementary function, base function