成层土中轴横受荷桩水平响应的非线性解

对于承受轴向荷载的水平受荷桩,以往研究大多基于线弹性或弹塑性水平荷载传递模型。为提升轴横受荷桩的计算设计水平,采用轴向荷载传递法计算桩身轴力,考虑桩身轴力引起的P-Δ效应,基于双曲线型水平荷载传递模型考虑桩-土体系变形的非线性特征,对成层土中轴横受荷桩的水平响应进行分析求解,得到了轴横荷载作用下桩身变形和内力的非线性有限差分解,并采用MATLAB语言编制了计算程序。使用模型试验算例与基于现场试验的有限元算例对非线性解的准确性进行对比验证,结果表明:计算结果与算例数据吻合良好,可靠性较高;采用不同荷载传递模型的计算结果在不同荷载水平下有所差异,在较大荷载水平下桩-土变形的非线性特点不容忽视。

Nonlinear solutions of lateral response for piles under axial and lateral load embedded in layered soils

Most of the previous studies were based on the linearly elastic or linearly elastic-plastic horizontal load transfer model for the laterally loaded piles undergoing axial load.In order to improve the calculation and design accuracy of axially and laterally loaded piles, considering the P-Δ effect caused by axial force of piles using the axial load transfer method, this paper proposes a nonlinear analysis approach based on hyperbola load transfer model to calculate the lateral response of elevated piles embedded in layered soils.The nonlinear finite difference solutions of the deformation and internal force for the pile shaft are obtained, and the relevant computer program is developed by MATLAB software.The accuracy of the nonlinear solutions is verified by utilizing the model test and the finite element calculation based on the field test.The calculation results showed that the results obtained by the nonlinear approach are in good agreement with the model test and finite element data.Besides, the results calculated by the approaches with different load transfer models are compared under different load levels.The nonlinear characteristics of pile-soil deformation cannot be ignored in calculation of lateral pile responses under large load.