考虑波动效应的SH简谐地震波作用下单桩水平振动研究

借助于土体的一维波动模型求解了SH简谐地震波作用下土层的水平振动，从三维轴对模型出发考虑桩周土的水平波动效应，通过引入势函数并运用分离变量法在考虑桩–土相互作用的情况下求解了SH简谐地震波作用下由于桩土相互作用引起的土层的径向位移、水平位移以及土体对桩基的水平作用力，并在此基础上建立了SH简谐地震波作用下桩基的水平振动方程，借助于三角函数的正交性和桩–土接触面处的连续条件求得了桩基的水平位移。借助于放大因子的概念研究了SH简谐地震波对桩顶水平位移的影响。研究表明：SH简谐地震波作用下桩基的动力响应存在有共振现象；放大因子随频率的变化曲线存在3个峰值，前两个峰值相对较大；当桩土模量比较大时桩土模量比对放大因子几乎没有影响。

Lateral vibration of a single pile under SH harmonic seismic waves considering three-dimensional wave effect

The lateral vibration of the soil under SH harmonic seismic waves is solved by one-dimensional model of wave motion.On the basis of three-dimensional soil model and taking consideration of wave effect of soil,the radial displacement and horizontal displacement caused by pile-soil interaction and the lateral soil force on the pile are obtained by means of the potential functions and variable separation method,and the lateral dynamic equation of the pile is established by considering the orthogonality of trigonometric function and the continuous conditions at the soil-pile contact surfaces.The influence of the SH harmonic seismic waves on the horizontal displacement of the pile head is investigated by the concept of magnification factor.The results indicate that the dynamic response of the pile under SH harmonic seismic waves has resonance.There are three peaks of the curves of amplification factor versus frequency,and the first two peaks are relatively larger.The pile-soil modulus ration has little effect on the amplification factor when the pile-soil modulus ration is larger.