基于非对称双侧破坏模式的临坡地基承载力上限分析

An upper-bound limit analysis of ultimate bearing capacity of ground foundation adjacent to slope based on asymmetric and bilateral failure mode

临坡地基已成为一种广泛的地基形式。针对临坡条形基础地基破坏模式的非对称性特点,首先引进双侧破坏模式的研究思路,重点考虑临坡地基基础两侧滑块大小和同一滑块几何形状的双重非对称性特征,构建了临坡条形基础地基非对称双侧破坏模式,为临坡地基承载力分析奠定了坚实基础;然后在此基础上,引进极限上限分析和优化理论,建立了临坡条形基础地基承载力分析的模型与方法,该方法不仅可考虑地基破坏模式,还可考虑基础与坡顶距离对临坡地基承载力的影响,而且还可较好地蜕化为平地地基承载力的分析;最后通过工程实例计算,并与现有相关分析方法进行对比分析,表明该方法的可行性与合理性以及普遍适用性。

Ground foundation adjacent to slope is already a universal foundation form. In view of the asymmetric failure characteristic of strip footing adjacent to slope, a bilateral failure model is developed. In this model, the double asymmetrical features are that the rigid sliding block sizes under both sides of strip footing or the geometry shape of the same slider is not identical. Based on the aforementioned mode, a new method for ultimate bearing capacity of strip footing adjacent to slope are put forward by adopting the upper-bound limit analysis method and optimization theory. The proposed precedure can reflect the influences of both the failure mode and the distance between strip footing and slope top on the bearing capacity of strip footing. At the same time, it could be degenerated well to determine the ultimate bearing capacity of the ground foundation. The feasibility, rationality and universal applicability of the approach are verified by the comparative analysis of results of engineering cases with existing methods in literature and the one in this paper.