层状地基群桩沉降计算的剪切位移解析算法

Analytical solution for settlement of group piles in layered ground based on shear displacement method

考虑群桩的"束缚作用",基于剪切位移法的理论,提出了竖向荷载作用下用于层状地基大规模群桩沉降分析的简捷实用的解析算法。以单桩位移积分方程为基础,导出了桩顶位移与轴力和桩底位移与轴力之间的关系,考虑桩-桩相互作用,得出了计算群桩沉降的柔度矩阵方程。推导过程中,桩被分成任意n段,因此该方法可以用于地基土任意分层的群桩沉降计算。算例分析表明,该方法与边混合法和界元法有较好的一致性。

A simple and practical analytical solution is presented for the analysis of settlement of the large group piles embedded in layered ground under vertical load. The approach is based on the shear displacement method and ＇restrain action＇ among piles in group is considered. On the basis of displacement integral equation of a single pile, the relationship between pile head displacement and the axial force is deduced, and so does the relation of pile tip displacement and the axial force. Then, considering the interaction between piles, a flexibility matrix that can be used to compute the settlement of group piles is obtained. On the process of the deducing, the group piles is arbitrarily divided into n segments; thus the presented method can be used to calculate the settlement of group piles in arbitrary layered ground. A case history indicateds that the settlements of group piles computed by the presented method agree reasonably well with those by the hybrid layer method and boundary element method （BEM）.