考虑沉桩挤土效应的楔形管桩纵向振动特性

基于剪切复刚度传递方法研究考虑沉桩挤土效应的楔形管桩纵向振动特性。首先,根据楔形管桩特殊的桩身结构并考虑桩周土的成层性,将桩-土体系沿竖向划分为若干段,进一步地,将桩周土沿径向划分为若干环形圈层以考虑沉桩过程中的挤土效应导致的土体径向非均质性；逐圈层求解土体动力平衡方程并通过相邻圈层间剪切复刚度的传递得到桩-土界面的剪切复刚度,求解桩的动力平衡方程,并结合Laplace变换和阻抗函数递推的方法,得到楔形管桩桩顶复阻抗频域响应解析解；通过与已有解答的对比证明了本文解的可靠性,在此基础上,分析了楔形管桩桩身参数及沉桩过程中的挤土效应对低频范围内桩顶复阻抗的影响。

Longitudinal Vibration of a Tapered Pipe Pile Considering the Compacting Effect During the Pile Installation

Based on the shear complex stiffness transfer method, the longitudinal vibration of a tapered pipe pile is investigated considering the compacting effect during the pile installation. First, the pile-soil system is divided into several segments in consideration of the special structure of the pile body and the stratification of the surrounding soil. Further, the surrounding soil is subdivided into finite annular zones in the radial direction to consider the radial inhomogeneity of the soil due to the compacting effect during the pile installation. The shear complex stiffness at the pile-soil interface is obtained by solving the dynamic equilibrium equation for each soil zone and combining with the transfer of the shear complex stiffness at the interface of the adjacent soil zones. Then, the analytical solution in the frequency domain for the complex impedance at the head of the tapered pipe pile is derived by solving the equilibrium equation for the pile and together with the Laplace transform and impedance function transfer method. The reliability of the proposed solution is verified by comparing with the existing solutions. On this basis, the influence of the pile parameters and the compacting effect during the pile installation on the complex impedance of the tapered pipe pile is analyzed within the low frequency range.