Improved transfer coefficient method considering multistage sliding of rainfall landslides

Abstract

In the progressive failure process of multiple landslides, different parts of the slip zone have different yielding degrees and failure modes with different strength parameters. Under strong rainfall conditions, water-filled tension cracks generated on the slope surface give rise to hydrostatic pressure. The current widespread transfer coefficient method, which takes the same strength parameter for different locations of the slip zone, also has not yet taken into account the hydrostatic pressure effect. In this paper, we propose an improved transfer coefficient method which takes into account the hydrostatic pressure effect and the difference in strength parameters of different parts of the slip zone. The results show that, compared with the calculation method without considering the hydrostatic pressure and the difference in strength parameters in different parts of the slip zone, the anti-sliding force calculated by the improved transfer coefficient method is relatively small, the residual sliding force is relatively large, and the stability coefficients of landslides at all levels are reduced by approximately 33.26%, 17.92%, 24.95% and 16.94%, respectively. Based on the high stability coefficient before the improvement, it may lead to insufficient safety reserve of the retaining engineering. The improved transfer coefficient method proposed in this paper can provide a safer reference for multiple landslide disposal.

Keywords

• improved transfer coefficient method
• multiple landslide
• stability evaluation
• landslide progressive failure characteristics
• hydrostatic pressure effect
• rainfall