水平振动荷载作用下支盘桩模型试验研究  

Model Test Study of Squeezed and Branch Pile under Horizontal Vibration Load

作　　者：吕冰[1] 高笑娟[1] 钟国华[1] 

机构地区：[1]河南科技大学土木工程学院,河南洛阳471003

出　　处：《建筑科学》2014年第9期45-50,共6页Building Science

基　　金：河南省教育厅课题(2010B560005);河南科技大学博士基金资助项目(09001210)

摘　　要：基于自行设计的桩-土动力相互作用模型试验装置,对2根承力盘位置不同的模型支盘桩施加强烈水平振动荷载,采用数字式变频仪控制荷载频率,通过不同弹簧的刚度系数实现不同大小的荷载级别,分析不同激振频率和激振荷载作用下桩身弯矩变化趋势及桩侧土压力变化状况。试验表明:随着激振频率的增大,支盘桩的动力响应在整体上有减小的趋势且水平动承载力有所提高;随着激振荷载的增大,支盘桩的动力响应随深度增加逐渐减小,反弯点位置逐渐下移,桩身的最大动弯矩发生在距桩顶1/3左右深度处。承力盘的设置改变了桩身的变形和受力状态,能够提高桩身平衡弯矩的能力,是对桩基的结构优化设计,且承力盘设置在桩身靠上有利于水平动承载力的提高。Based on the self-design model experimental system of dynamic soil-pile interaction, the strong horizontal dynamic load is exerted to two models of squeezed and branch pile with different set of beating plate location, digital frequency converter is adopted to control the loading frequency, different stiffness coefficients of the spring are used to achieve different load level, and the action of bending moment of pile change trend and the status of the pile lateral soil pressure changes under different vibration frequency and vibration load are analyzed. The results show that with the increase of vibration frequency, the dynamic response of squeezed and branch pile has a tendency to decrease on the whole, the position of the inflection point is gradually downward. The maximum dynamic bending moment of pile body occurs in about one third the depth of the pile top. The pile deformation and stress state are changed with the set of bearing plate, and the ability of pile body balance bending moment is improved, which is a structure optimization design of pile foundation and beneficial to the improvement of the horizontal dynamic beating capacity while setting beating plate on the pile body.

关 键 词：支盘桩 水平振动 模型试验 桩-土相互作用 

分 类 号：TU443[建筑科学—岩土工程]