Abstract

The present paper evaluates the seismic bearing capacity of a strip footing lying near the edge of a rock slope. Resorting to the framework of the limit analysis kinematic approach formulated in the context of pseudo-static method, the analysis assesses the reduction in ultimate bearing capacity (UBC) provoked by the combined effects of the proximity of rock slope and seismic loading. The nonlinearity of the strength properties of rock material is modeled by means of a modified Hoek-Brown failure criterion. At the structure level, the closed-form expressions derived for the support functions associated by duality with such a failure criterion allow deriving rigorous upper bound solutions for the UBC. Particular attention is paid to the description and implementation of the generalized multi-wedge failure mechanism, which proves efficient to predict the stability conditions. The approach is then applied to investigate the effects of relevant geometry, strength and loading parameters. The approach accuracy is evaluated by comparison of the obtained predictions with existing limit analysis results, as well as with lower and upper bound finite element solutions, thus emphasizing the proposed approach efficiency to evaluate the reduction in UBC induced by slope proximity in the static and seismic cases.

摘要

本文评估了靠近岩石边坡边缘的条形基础的抗震承载能力。借助在拟静力法背景下制定的极限分析运动学方法的框架，该分析评估了岩石边坡附近和地震载荷的综合影响引起的极限承载力 (UBC) 降低。岩石材料强度特性的非线性通过改进的 Hoek-Brown 失效准则进行建模。在结构层面，为由对偶关联的支持函数导出的封闭式表达式与这种失效准则允许导出 UBC 的严格上限解。特别关注广义多楔失效机制的描述和实现，这证明对预测稳定性条件是有效的。然后应用该方法来研究相关几何形状、强度和载荷参数的影响。通过将获得的预测与现有极限分析结果以及下限和上限有限元解进行比较来评估逼近精度，从而强调所提出的逼近效率，以评估静态和地震中边坡邻近引起的 UBC 减少案例。