非完全粘结下饱和土中桩扭转振动的解析解-岩土之星.PDF

第 31 卷第 7 期 Vol.31 No.7 工 程 力 学 2014 年 7 月 July 2014 ENGINEERING MECHANICS 156 1000-4750(2014)07-0156-06 闻敏杰 1,2，徐金明2 (1. 嘉兴职业技术学院生物与环境分院，浙江，嘉兴 314036 ；2. 上海大学土木系，上海 200072) 采用解析方法研究了桩土界面非完全粘结条件下饱和土中端承桩的扭转振动问题。利用 Kelvin 模型模拟 饱和土层和端承桩接触面的相对滑移，与以往桩土界面连续性模型进行了对比。根据 Biot 波动原理，采用 Novak 薄层法推导了饱和土层对扭转振动桩的动力阻抗。将端承桩等效为 Euler-Bernoulli 杆模型，给出了桩顶动刚度因 子和等效阻尼随激励频率的响应。通过算例分析了相对滑移和连续性两种模型条件下桩顶刚度因子和等效阻尼的 差异。结果表明：当外荷载激励频率较大时，完全粘结条件下桩顶动刚度和动阻尼的振幅小于滑移条件下桩顶动 刚度和动阻尼的振幅。因此，采用非完全粘结条件模拟桩土接触面更为合理。 饱和土；端承桩；非完全粘结；接触面；扭转振动；解析解 TU435 A doi: 10.6052/j.issn.1000-4750.2013.01.0094 ANALYTICAL SOLUTION FOR TORSIONAL VIBRATION OF A PILE IN SATURATED SOIL CONSIDERING IMPERFECT CONTACT WEN Min-jie1,2 , XU Jin-ming2 (1. Department of Biological and Engviromental Engineering , Jiaxing Vocational Technical College, Jiaxing, Zhejiang 314036, China; 2. Department of Civil Engineering, Shanghai University, Shanghai 200072, China) Abstract: Using analytical method, the problem for torsional vibration of end-bearing pile in saturated soil is studied under the imperfect contact between pile and soil. The imperfect contact of saturated soil layer and end-bearing pile is described by Kelvin model, which is compared with the previous continuity model. Based on Boit’s theory, the dynamic impedance of the saturated soil to torsional vibration of the pile is obtained by Novak’s layer method. The end-bearing pile is treated as Euler-Bernoulli rod mode. The responses of dynamic stiffness factor and equivalent damping of pile top against the frequency are shown in figures. The differences for stiffness factor and equivalent damping at the pile top between imperfect contact