【摘要】 为研究地基土体剪切刚度沿深度变化对横向受荷桩工作性状的影响,基于Newmark法和Pasternak双参数地基模型,假设土体剪切刚度为幂函数分布,由单元的挠曲微分方程求得了各结点的横向抗力。忽略了土体压缩变形和剪切变形的耦合作用后,对各结点的横向抗力做了简化,进而导出了单元的场传递矩阵及桩的总体传递矩阵;根据桩底边界条件,求得了桩的初始状态向量,确定了各结点的状态向量。算例分析表明:土体的剪切作用对减小顶位移和桩身最大弯矩有一定的贡献,且对中长桩的影响较长桩明显;土体剪切刚度沿深度变化对桩顶位移影响很小,地面处土体剪切刚度对其影响较大,双参数地基模型能够更好的模拟桩土的实际工况。更多还原

【Abstract】 To analyse the effect of the subsoil shear stiffness varying with depth on working properties of laterally loaded piles,based on the Newmark method and the double-parameter foundation model,the horizontal resisting force of nodes were obtained by solving the unit bending differential equation,assuming of power function distribution model of the subsoil shear stiffness.To simplify the horizontal resisting force of nodes,the coupling effect of compression and shear of soil was neglected.Then,the field transfer matrix of element and total transfer matrix of pile have been deduced.According to boundary conditions of pile bottom,the initial state vector was obtained.And then,the state vectors of nodes were determined.The case study indicates that the shear effect of subsoil is helpful to reduce the displacement of pile top and the maximum bending moment of pile,and this influence on middle long pile is more obvious than long pile.The displacement of pile top is mainly influenced by the subsoil shear stiffness at the ground surface and with little effect by the subsoil shear stiffness varying with depth.The double-parameter foundation model can preferably describe practical working conditions between pile and soil.更多还原