考虑桩土相互作用效应的桩顶纵向振动时域响应分析

在考虑桩土耦合作用以及土竖向波动效应条件下，对均质滞回材料阻尼土中弹性支承桩桩顶纵向振动时域响应进行了理论研究。首先建立了桩与滞回阻尼土在谐和振动情况下的定解问题，然后先对土层动力平衡方程进行求解并得到土体振动位移形式解，接着依据平衡条件将该形式解祸合进桩身动力平衡方程，并通过对桩动力平衡方程的求解，最终得到桩顶位移和速度频域响应解析解和半正弦脉冲激励作用下桩顶时域响应的半解析解。通过与其它相关理论解的对比验证了本文解的正确性和适用性，并基于所得解对桩顶时域响应特性进行了分析，最后将理论曲线与现场工程实测曲线进行了拟合对比，结果表明两者符合较好。

Time domain analysis of vertical dynamic response of a pile considering the effect of pile-soil interaction

Considering soil-pile interaction and vertical wave effect of soil around pile, the dynamic vertical response of a pile in time domain is investigated theoretically. The pile is assumed vertical and with elastic bottom boundaries and the soil is considered as visco-elastic layer with hysteretic type damping. The soil layer alone is solved first and its vibration displacement solution with undecided constants is used in the analysis of pile response. Then by solving dynamic equilibrium equation of pile, the pile response to a harmonic load is obtained in a closed form and a semi-analytical solution of the velocity response of pile subjected to a semi-sine wave exciting force is also given. In comparison with other theories, the correctness and applicability of the theoretical solutions presented herein are verified. Based on the solution, A parametric study is conducted to determine the main features of dynamic response of pile in time domain. It is shown that the theoretical curves are in good agreement with those obtained from on-site test.