低应变下变阻抗薄壁管桩动力响应频域解析解  

Analytical solution in frequency domain of dynamic response of thin-wall pipe piles with variable wave impedance under low strain transient concentrated load

作　　者：丁选明[1,2] 刘汉龙[3,2] 

机构地区：[1]河海大学水资源高效利用与工程安全国家工程研究中心,南京210098 [2]河海大学岩土工程科学研究所,南京210098 [3]河海大学岩土力学与堤坝工程教育部重点实验室,南京210098

出　　处：《岩土力学》2009年第6期1793-1798,共6页Rock and Soil Mechanics

基　　金：国家自然科学基金资助(No.50679017);江苏省自然科学基金创新学者攀登项目(No.BK2008040);江苏省青蓝工程创新团队资助项目

摘　　要：管桩低应变完整性检测时,桩顶一点受到瞬态集中荷载的作用,其动力响应问题是一个三维波动问题。基于三维波动理论,建立了任意段变阻抗薄壁管桩动力响应的计算模型和波动方程,结合初边值条件,采用Laplace变换法求得了该波动方程的频域解析解,采用Fourier逆变换求得了时域响应。将计算结果与三维有限元结果进行了对比分析,解析解的计算结果和三维有限元结果较为接近,两者在入射波峰、缺陷反射峰和桩底反射峰处都较为吻合,两种方法位移响应曲线基本相同。给出了桩顶不同点的动力响应,并探讨了高频干扰问题。对变截面桩和变模量桩的动力响应特性进行了分析。Dynamic response of pipe piles under low strain transient concentrated load is a three dimensional wave problem. Based on the three dimensional wave theory, the computational model and wave equation of dynamic response of thin-wall pipe piles with variable wave impedance are established. Combined the initial and boundary conditions, the analytical solution of wave equation in frequency domain is obtained by Laplace transformation method. The time domain response is obtained by Fourier inverse transformation. By comparing the results of analytical solution with that of 3D finite element method, the following conclusions are achieved： the wave crest of the results of analytical solution can well meet that of the 3D-FEM results; and the displacement responses of them have little difference. The dynamic responses at different points on top of the pile and the high-frequency interference problem are also researched. The characteristics of dynamic responses of variable modulus piles and variable section piles are studied.

关 键 词：薄壁管桩 低应变检测 动力响应 三维效应 解析解 

分 类 号：TB115[理学—数学]