成层非饱和土中桩的纵向振动特性分析  

A Study on Longitudinal Vibration Behavior of Inhomogeneous Pile Embedded in Layered Unsaturated Soils

作　　者：张智卿[1] 王奎华[1] 谢康和[1] 周开茂[1] 

机构地区：[1]浙江大学土木工程系,杭州310027

出　　处：《科技通报》2007年第1期88-96,共9页Bulletin of Science and Technology

基　　金：国家自然科学基金资助项目(批准号:50279047);浙江省自然科学基金资助项目(批准号:Y104413)

摘　　要：基于Bishop有效应力公式,单相流固结理论,以及阻抗函数递推方法研究了三维轴对称条件下成层简化的非饱和土中变截面桩的纵向振动特性。在频域中,求得了桩顶位移和速度的响应函数。利用傅里叶逆变换,得到了瞬态半正弦脉冲荷载作用下桩顶时域响应的半解析解。通过数值计算,分析了土层模量变化、土层饱和度变化以及桩身截面变化对桩顶频域和时域响应曲线的影响。结果表明,土层模量变化对桩顶频域和时域响应有一定的影响,土层饱和度变化基本没有影响,桩身截面变化影响较大。Based on Bishop＇s effective stress formula, the dynamic response of an inhomogeneous pile embedded in layered simplified unsaturated soil and subjected to a vertical load is theoretically investigated. And the corresponding solutions of the displacement and velocity response function at the pile head are derived in frequency domain. Then, a semi-analytical solution for the velocity response of the pile subjected to a semi-sine wave exciting force is derived by using invert Fourier transform. Through numerical calculation, the influences of the variations of the modulus and degree of saturation of soil layer and cross-section of the pile on the response are analyzed. It is shown that the variation of the modulus of soil layer has some influence on the response, that of the degree of saturation of the soil layer has no influence on the response and the change of cross-section of the pile has remarkable influence on the response.

关 键 词：非饱和土 阻抗函数 纵向振动 导纳 反射波 

分 类 号：TU-43[建筑科学]