层状饱和土中管桩瞬态扭转振动研究  

Transient torsional response of a pipe pile embedded in layered saturated soil

作　　者：赵仓龙 章敏[1,2] 李亚楠 张宏宇 ZHAO Canglong;ZHANG Min;LI Yanan;ZHANG Hongyu(School of Civil Engineering,Taiyuan University of Technology,030024 Taiyuan,China;Engineering Research Center of Railway Environment Vibration and Noise,East China Jiaotong University,330013 Nanchang,China;Shaanxi Architectural Design and Research Institute,710018 Xi'an,China)

机构地区：[1]太原理工大学土木工程学院,太原030024 [2]华东交通大学铁路环境振动与噪声工程研究中心,南昌330013 [3]陕西省建筑设计研究院(集团)有限公司,西安710018

出　　处：《应用力学学报》2022年第3期516-526,共11页Chinese Journal of Applied Mechanics

基　　金：中国博士后科学基金(No.2020M671960)。

摘　　要：对瞬态扭转激振荷载作用下层状饱和土中端承管桩的动力响应问题进行了研究。首先借助Laplace变换和分离变量法解耦Biot波动方程,土层层间动力相互作用简化为分布式线弹簧,并结合桩-土交界面上的应力和位移连续边界条件,导出了各节段管桩在Laplace变换域内扭转动力响应的解析表达式;然后,根据阻抗函数传递原理,并对得到的解进行Laplace数值逆变换,最终获得了瞬态扭转荷载作用下层状饱和土中管桩动力响应的时域解答。研究表明:桩顶作用三角形或半正弦荷载情况下,最大桩顶扭转角产生时刻落后于最大荷载对应时刻;且当桩周土渗透系数处于相对较高和较低范围内,桩顶转角几乎保持不变,在中间范围内则随渗透系数增大而增大;硬夹层的存在将使桩身上部扭矩增大,下部扭矩减小,软夹层下规律相反。Dynamic response of an end-bearing pipe pile subjected to transient torsional loading in layered saturated soil is theoretically studied in this paper.First,Biot’s wave equation is decoupled by recourse to Laplace transform technique and separation of variables,and a series of distributed linear springs are utilized to simulate the dynamic interaction between the soil layers.By combined with the continuity and boundary conditions of pile-soil interface,the torsional dynamic response of an arbitrary pile segment is further derived in the transformed domain.Then,according to the principle of the recursion of impedance functions and by means of inverse Laplace transform,the time-domain solutions of pipe pile under transient torsional loading embedded in a layered saturated soil are finally obtained.Numerical results show that the time corresponding to maximum twist angle atop the pile lags behind that of maximum loading when subjected to triangular or semi-sinusoidal loads.The twist angle atop the pile almost remains constant in the case of outer soil with relatively high or low permeability coefficients,whereas it gradually increases in the middle range of the permeability.The hard interlayer soil increases the torque of upper part of the pile and decreases that of the lower part,while the effect of soft interlayer soil is inverse.

关 键 词：管桩 层状饱和土 扭转 瞬态振动 

分 类 号：TU47[建筑科学—结构工程]