Assessment of rigorous solutions for pseudo-dynamic slope stability: Finite-element limit-analysis modelling

• Published in: Journal of Central South University 2023-07, Vol.30 (7), p.2374-2391
• Main Authors: Zhou, Jian-feng, Zheng, Zi-yu, Bao, Ting, Tu, Bing-xiong, Yu, Jian, Qin, Chang-bing
• Format: Article
• Language: English
• Subjects: Algorithms; Bearing capacity; Dynamic stability; Engineering; Finite element method; Flow stability; Linear programming; Lower bounds; Mathematical models; Metallic Materials; Safety factors; Seismic stability; Slope stability; Soil dynamics; Soil layers; Soil strength; Stability analysis; Upper bounds
• ISSN: 2095-2899; 2227-5223
• DOI: 10.1007/s11771-023-5370-0

This study developed a finite-element lower-bound procedure to investigate seismic slope stability in homogeneous and non-homogeneous soils. In order to account for dynamic earthquake inputs, horizontal and vertical accelerations are expressed by the pseudo-dynamic approach, in the form of sinusoidal functions. Within the framework of lower-bound theory, the seismic slope stability analysis is transformed to a linear programming problem subjected to: stress equilibrium, stress discontinuity, stress boundary and yield conditions. An interior-point algorithm implemented into MATLAB was adopted to seek optimal lower-bound solutions of slope bearing capacity and safety factor. The proposed procedure for lower-bound analysis of seismic slope stability was validated by comparing the slope safety factor obtained from different approaches including limit equilibrium and Abaqus. A nonuniform soil slope with linearly varied and layered soil strength parameters and non-associated flow rule are considered, and the corresponding effects on seismic slope stability are discussed. The true solution of safety factor to seismic slope stability is well assessed by rigorous lower and upper bounds with the discrepancy no greater than 4.5%.