基于能量法的陡坡段桥梁基桩屈曲稳定性分析

摘要

A theoretical model for bridge pile buckling in steep slope, by which the influence of distribution of landslide-thrust behind the pile as well as the weakening of the horizontal resistance of foundation in front of the pile would be considered, was further developed. The analyses were performed based on the total potential energy equation of the pile-soil system, and the solution of stability calculation length was obtained by using energy method. The parametric analyses were conducted, such as elastic modulus, diameter, and the embedded depth of pile. The results show that the calculated results from the proposed model demonstrate a good agreement with the experimental observation. The embedment ratio of pile, the critical ratio of length to diameter, and the critical embedded depth have significant influences on the buckling stability of pile.%考虑桩后坡体剩余下滑力的分布规律，以及桩前岩土体水平地基抗力弱化效应对基桩稳定性的影响，建立陡坡段桥梁基桩屈曲稳定分析计算模型。通过建立桩土体系的总势能方程，并运用能量法导得陡坡段桥梁基桩屈曲临界荷载和稳定计算长度解答。以实际工程基桩为例对影响基桩屈曲稳定性的桩身弹性模量、桩径、嵌固深度等因素进行参数分析。研究结果表明：本文计算结果与已有模型试验结果吻合较好，表明本文解答合理。基桩的埋入比、临界长径比及临界嵌固深度对其屈曲稳定性具有显著影响。