Static and seismic stability assessment of 3D slopes with cracks: Fid-Bau Portal

Static and seismic stability assessment of 3D slopes with cracks

Li, Zheng-Wei / Yang, Xiao-Li / Li, Tian-Zheng

Abstract The majority of extant analyses on slope stability assumed a two-dimensional plane-strain condition and/or an intact slope. However, slope failures typically exhibit three-dimensional (3D) characteristics and cracks are commonly present in cohesive slopes. This study develops a framework based on the kinematic limit-analysis method for static and seismic stability evaluation of 3D slopes with cracks. A pseudo-static approach is adopted to represent seismic effects. Two types of cracks are considered: cracks prior to slope failure (open cracks) and cracks forming contemporaneously with slope failure (formation cracks). A 3D horn-like collapse mechanism including a vertical crack is used to represent the slope collapse. A comparison with previous studies is conducted to validate the proposed approach. A series of stability charts is presented for the ease of direct use. Results show that consideration of seismic effects and existence of cracks lead to a significant reduction in slope stability, whereas the inclusion of 3D effects yields a greater safety factor. The influence of cracks becomes more significant for slopes with greater inclination angles and higher levels of soil cohesion. This study considers a more realistic situation, the results of which can serve as a reference tool in the seismic design of slopes.

Highlights • Static and seismic stability of 3D slopes with cracks is studied. • The influence of both open cracks and formation cracks is included. • Considering seismic effects and existence of cracks will reduce slope stability • The inclusion of 3D effects yields a greater safety factor • The effect of cracks is more significant at greater inclination angles and higher levels of soil cohesion.