砂土地基斜桩水平承载特性p-y曲线法

基于Reese建议的砂土p-y曲线，提出了适用于斜桩水平承载特性分析的修正p-y曲线及相应的有限元分析方法。根据桩前土体受力特点，假设桩前浅层土体达到极限破坏状态时桩侧被动破坏区为一个三维楔形体，采用极限平衡分析方法导出了斜桩桩侧极限土抗力表达式，对比研究了斜桩倾角、桩-土界面摩擦系数等因素对极限土抗力的影响规律，并给出了斜桩初始地基反力模量确定方法。在此基础上，修正Reese提出的直桩p-y曲线，提出了砂土地基中斜桩p-y曲线确定方法。利用虚功原理，导出了斜桩水平承载特性分析的有限单元列式，编制相应的分析程序，通过算例验证了方法的合理性和有效性。最后，采用修正的p-y曲线法对一离心机模型试验进行了模拟分析，结果表明，计算与试验结果吻合得很好

A p-y curve method for horizontal bearing characteristics of single batter pile in sands

Based on the p-y curve method for plumb pile in sand proposed by Reese, a new p-y curve method and its corresponding finite element method for analyzing horizontal bearing characteristics of single batter pile are presented. Firstly, according to the mechanical behavior of the shallow soil near a batter pile, a three-dimensional wedge model is put forward to describe the passive region which is in the limit state. By using limit equilibrium analysis method, the expression of ultimate soil resistance of batter pile is derived. Then, the influences of pile angle and the friction between pile and soil are numerically studied; and the method for determining the initial modulus of p-y curve of batter pile is given. By modifying the p-y curve for plumb pile in sands proposed by Reese, the p-y curve for batter pile in sand is obtained. Using the virtual work principle, the finite element formulations for horizontal bearing analysis of single batter pile are deduced; and the iteration algorithm is put forwards. The corresponding program is coded by authors; and numerical examples are taken to illustrate the effectiveness of the method. Finally, a printed centrifuge model test of batter pile is analyzed by the presented method. The numerical results show fine agreement with those of model test.