A rapid estimation method of the safety factor and critical stability charts for non-straight slopes with one convex fold angle

Abstract

At present, almost all stability charts are designed for uniform slopes with straight surfaces. In this study, the main purpose is to provide a new stability chart analysis method, which is applicable to assess the stability of a non-straight slope with one convex fold angle. First, critical failure state charts (CFSCs) are proposed to represent the relationship among the slope height, unit weight, soil cohesion and friction angle for different slope angles when the slopes are in a critical failure state. Second, based on the CFSCs, the safety factors for any non-straight slope with one convex fold angle can be directly determined by solving quadratic equations with one unknown. Finally, the reliability and accuracy of the proposed method is tested against the limit equilibrium method (LEM) and finite-difference strength-reduction method (SRM) via 12 slope examples. The results show that the average relative errors, compared with the LEM and SRM, are 3.84% and 3.16%, respectively. Thus, it can be concluded that the proposed method has good performance in terms of calculating the FOS.

Keywords

• slope stability analysis
• factor of safety
• limit equilibrium method
• mohr–coulomb failure criterion
• critical stability chart