A new perspective on determination of the critical slip surface of three-dimensional slopes

• Published in: Computers and geotechnics 2022-11, Vol.151, p.104946, Article 104946
• Main Authors: Sun, Jiaping, Yu, Tiantang, Dong, Pingting
• Format: Article
• Language: English
• Subjects: 3D slope; Critical slip surface; Genetic algorithm; Minimum potential energy principle; Safety factor; Sliding direction
• ISSN: 0266-352X; 1873-7633
• DOI: 10.1016/j.compgeo.2022.104946

In the traditional slope stability analysis, the shape and location of critical slip surface (CSS) are identified by an objective function with the minimum safety factor (SF). However, the method cannot identify the true CSS when the minimum SFs of different critical slip surfaces are equal or extremely close. In order to solve the issue, the idea of slip surface with the maximum sliding direction (SD) as the CSS is proposed in this paper. The shape of CSS is regarded as a rotational ellipsoid with 6 parameters, and the genetic algorithm (GA) is adopted to search for the location of CSS. The three-dimensional (3D) slope stability analysis is performed based on the minimum potential energy principle, which provides an analytical formulation of SD as well as SF without iteration. Two benchmark slopes and a practical engineering case are employed to verify the rationality of the proposed method. The parametric analysis reveals that the larger SD the smaller SF. The developed method is a useful technique support for determining the CSS and the shape of 3D slope. •A new criterion is developed for determining the critical slip surface of 3D slopes.•The relationship between the sliding direction and the safety factor is explored.•Influence of some parameters on the sliding direction and safety factor are investigated.•The sliding direction and safety factor are insensitive to the foundation coefficient.