非饱和地基中部分埋入桩的水平振动问题  

Horizontal vibration of partially embedded piles in unsaturated foundation

作　　者：杨紫健 刘浩[1] 张云鹏[1] 邱敏 吴文兵[1,2] YANG Zi-jian;LIU Hao;ZHANG Yun-peng;QIU Min;WU Wen-bing(Faculty of Engineering,China University of Geosciences,Wuhan 430074,China;Zhejiang Institute,China University of Geosciences,Hangzhou 311305,China;CCCC Second Maritime Engineering Bureau Co.Ltd.,Wuhan 430040,China)

机构地区：[1]中国地质大学工程学院,湖北武汉430074 [2]中国地质大学浙江研究院,浙江杭州311305 [3]中交第二航务工程局有限公司,湖北武汉430040

出　　处：《振动工程学报》2023年第1期247-255,共9页Journal of Vibration Engineering

基　　金：中国博士后科学基金(2020M673093);广东省海洋土木工程重点实验室开放基金(LMCE202003);浙江省自然科学基金杰出青年项目(LR21E080005)。

摘　　要：本文研究非饱和土中部分埋入桩的水平振动问题,为模拟桥梁桩基的高承台桩的实际服役状态,考虑水平简谐荷载和竖向静载的组合作用,采用Timoshenko梁模型和三维连续介质建立了非饱和土⁃部分埋入桩的耦合振动理论模型,利用微分变换法和传递矩阵法求得了桩身水平动力响应解析解,将退化解与已有成果作比较,验证了本文解的合理性。基于建立的理论模型,探讨了竖向荷载、埋入比和饱和度对部分埋入桩水平动力特性的影响。研究结果表明:刚度因子随着竖向荷载的增大而迅速减小,但是阻尼因子略微减小;刚度因子和阻尼因子均随着埋入比的增加而减小;桩身水平位移、转角、弯矩和剪力幅值均随着埋入比的增大而增大,幅值位置逐渐向上移动;饱和度较低的对刚度因子的影响很小,但饱和度大于0.9时刚度因子随饱和度的增加而迅速增大,阻尼因子基本保持不变。In this paper,the horizontal vibration of partially embedded piles in unsaturated soil is mainly studied.In order to simu⁃late the real service state of high bearing platform piles of bridge pile foundation,considering the combined action of horizontal har⁃monic load and vertical static load,the coupled vibration theoretical model of unsaturated soil and partially embedded piles is estab⁃lished by using Timoshenko beam model and three dimensional continuum model.The analytical solution of horizontal dynamic re⁃sponse of pile is obtained by the decomposition technique of potential technique and the transfer matrix method.The rationality of the solution is verified by comparing the proposed solution with the results of previous scholars.Based on the established theoretical model,the influence of vertical load,embedding ratio and saturation on the horizontal dynamic characteristics of partially embed⁃ded piles are discussed in detail.The results show that:the stiffness factor decreases rapidly with the increasement of vertical load,but the damping factor decreases slightly at the time;Both stiffness factor and damping factor decrease with the increase of embed⁃ding ratio;The horizontal displacement,rotation angle,bending moment and shear amplitude of the pile increase with the increase⁃ment of the embedding ratio,and the amplitude position moves upward gradually;When the saturation is greater than 0.9,the stiff⁃ness factor increases rapidly with the increase of saturation,and the damping factor basically remains unchanged.

关 键 词：非饱和土 部分埋入桩 水平振动 动阻抗 Timoshenko梁模型 

分 类 号：TU435[建筑科学—岩土工程] TU473.1[建筑科学—土工工程]