现浇X形桩低应变动力检测足尺模型试验研究  

Full-scale model tests of low strain dynamic testing of X-section cast-in-place pile

作　　者：丁选明[1] 范玉明 刘汉龙[1,3] 黄宇航[3] 

机构地区：[1]重庆大学山地城镇建设与新技术教育部重点实验室,重庆400045 [2]上海申元岩土工程有限公司,上海200041 [3]重庆大学土木工程学院,重庆400045

出　　处：《岩石力学与工程学报》2017年第A02期4290-4296,共7页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(51622803;51420105013)~~

摘　　要：为揭示异形截面X型桩的速度波传播机制,开展足尺X型桩的低应变动力检测试验,分别在桩顶和桩底布置测点,锤击桩中心,获得桩顶和桩底的速度响应曲线,研究X型桩低应变动测速度响应的三维效应和高频干扰问题。研究结果表明:沿凹弧方向和尖角方向的速度响应具有相似的规律,桩顶入射波的三维效应明显,而桩底反射波差别不大;距离桩心越远的点入射波波峰到达时间越滞后,入射波–反射波时间差越小;不同位置测点的速度响应波形受到不同程度高频干扰的影响,距离桩心0.4R^0.5R区域内测点的速度响应受高频干扰最小,边界处测点受高频干扰最显著;X型桩桩顶速度波形受到2种不同频率高频波的干扰。Full-scale model tests are carried out to reveal the propagation mechanism of velocity waves of Xsection pile in low strain dynamic testing.The velocity responses at various points are obtained by arranging measuring points at different locations at both pile top and pile bottom.The three-dimensional effect and high frequency interference of X-section pile in low strain testing are researched.The results show that the velocity responses in the direction of concave arc are similar with those in the direction of convex edge.The threedimensional effects of incident waves on pile top are obvious;however,the reflection waves from pile bottom are almost the same.The arrival time of incident waves is increased with the increase of the distance from the pile center,while the time difference between incident and reflection waves is decreased.The high frequency interferences at the location of 0.4 R to 0.5 R from pile center are unobvious,while they are more significant at the edge of pile section.There are two kinds of high frequency interference waves in velocity waves of X-section pile in low strain testing.

关 键 词：桩基础 现浇X型桩 桩身完整性检测 低应变动力检测 三维效应 高频干扰 

分 类 号：TU443[建筑科学—岩土工程]