Relationship between critical seismic acceleration coefficient and static factor of safety of 3D slopes

Abstract

Many analytical methods have been adopted to estimate the slope stability by providing various stability numbers, e.g. static safety of factor (static FoS) or the critical seismic acceleration coefficient, while little attention has been given to the relationship between the slope stability numbers and the critical seismic acceleration coefficient. This study aims to investigate the relationship between the static FoS and the critical seismic acceleration coefficient of soil slopes in the framework of the upper-bound limit analysis. Based on the 3D rotational failure mechanism, the critical seismic acceleration coefficient using the pseudo-static method and the static FoS using the strength reduction technique are first determined. Then, the relationship between the static FoS and the critical seismic acceleration coefficient is presented under considering the slope angle β, the fractional angle φ, and the dimensionless coefficients B/H and c/γH. Finally, a fitting formula between the static FoS and the critical seismic acceleration coefficient is proposed and validated by analytical and numerical results.

摘要

现有的理论分析方法主要通过提供各种稳定性系数, 例如静态安全系数或临界地震加速度系数 实现对边坡稳定性的评估, 而关于边坡安全系数与临界地震加速度系数的相关关系的研究较少。本文 在极限分析上限分析法的框架下, 探讨了三维边坡静态安全系数与临界地震加速度系数之间的关系。 基于三维旋转破坏机理, 首先, 采用拟静力法给出了边坡临界地震加速度系数和采用强度折减技术给 出了静态安全系数; 然后, 在考虑不同的坡角β、摩擦角φ 和无量纲系数B/H 和c/γH 的条件下, 研究 了静态安全系数与临界地震加速度系数的相关关系; 最后, 给出了静态安全系数与临界地震加速度系 数的拟合公式, 并通过理论结果和数值结果对所提出的拟合公式进行了验证。