现浇薄壁管桩低应变反射波法检测时瞬态波传播特性研究  

Propagation characteristics of transient waves in low strain integrity tests on cast-in-situ concrete thin-wall pipe piles

作　　者：刘汉龙[1] 丁选明[2] 

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210098 [2]河海大学岩土工程科学研究所,江苏南京210098

出　　处：《岩土工程学报》2008年第3期414-419,共6页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金资助项目(50679017);江苏省“六大人才高峰”基金资助项目(50528512)

摘　　要：现浇薄壁管桩低应变检测时,存在桩头三维效应以及平截面假定的适应性问题。基于笔者所建立的理论公式,计算了桩顶的速度和位移响应,对高频干扰频率及其影响因素进行了分析。提出了桩顶入射波峰大小及到达时间的数值计算方法,分析了其沿环向变化的规律以及半径和脉冲宽度的影响。对平截面假定的适应性进行了探讨,比较了不同深度截面各点的速度响应,速度响应曲线第一个峰值之后各点的波形会出现不同程度的"分岔"现象,平截面假定难以满足。The three-dimensional effects of pile head and applicability of plane-section assumption are main problems in low strain dynamic tests on cast-in-situ concrete thin-wall pipe piles.The velocity and displacement responses were calculated by a theoretical formula deduced by the authors.The frequency and influencing factor of high-frequency interference were analyzed.A numerical method was established to calculate the peak value and arrival time of incoming waves on top of the piles.The regularity along circumferential and the influence of radius or impulse width were studied.The applicability of plane-section assumption was investigated by comparison of velocity responses at different points in the sections at different depths.The waveform of velocity response at different points forked after the first peak,indicating that the propagation of stress waves didn’t well meet the plane-section assumption.

关 键 词：管桩 低应变完整性检测 动力响应 瞬态波 三维效应 

分 类 号：TU473[建筑科学—结构工程]