隧道开挖作用下桩基水平位移简化解析解  

Simplified theoretical solution of horizontal deformation of pile caused by tunnel excavation

作　　者：韦征 江玉生[1] 殷明伦 杨星 WEI Zheng;JIANG Yusheng;YIN Minglun;YANG Xing(School of Mechanics and Civil Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China;Postdoctoral Program,Beijing Urban Construction Group Co,Ltd.,Beijing 100088,China)

机构地区：[1]中国矿业大学(北京)力学与建筑工程学院,北京100083 [2]北京城建集团博士后工作站,北京100088

出　　处：《中南大学学报（自然科学版）》2022年第10期4106-4114,共9页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(U1261212)。

摘　　要：为研究隧道开挖卸荷下桩基的水平位移响应,把桩基简化为置于Winkler地基上的具有等效抗弯刚度的Euler-Bernoulli连续梁,提出一种计算既有桩基在邻近隧道开挖卸荷下的水平变形响应理论计算方法。采用Loganathan理论计算隧道开挖引起既有桩基位置处的自由土体水平位移;将桩基位置处的自由土体水平位移施加于既有桩基之上,基于桩基与地层土体的位移耦合条件建立桩基水平位移平衡方程;通过求解得到隧道近距离开挖引起桩基水平位移解析解。将理论计算结果与文献中的边界元模拟结果、有限元模拟结果和现场监测结果进行对比,验证了所提方法的正确性。最后,对隧道开挖引起桩基水平位移响应进行参数分析,提出计算隧道开挖引起桩基最大水平位移的参数预测公式。研究结果表明:桩基最大水平位移受隧道埋深、开挖尺寸、隧道与桩基间距影响较为显著,与隧道埋深近似呈线性增长关系,受桩径变化影响较小。In order to study rules of the horizontal displacement responses of the existing pile due to the crossing tunnel,a theoretical solution was presented for calculating the horizontal displacement response of an existing pile during the excavation and unloading of a nearby tunnel.The existing pile was simplified as an Euler-Bernoulli continuous beam with equivalent flexural stiffness placed on Winkler foundation.Loganathan's theory was used to calculate the horizontal displacement of free soil at the pile position caused by tunnel excavation.The horizontal displacement of free soil at the position of pile was applied to the existing pile,and the horizontal displacement equilibrium equation of pile was established based on the displacement coupling condition of pile and stratum soil.The theoretical solution of horizontal displacement of pile caused by tunnel excavation in short distance was obtained by finite difference method.The correctness of the proposed method was verified by comparison with the results of boundary element simulation,finite element simulation and filed measurement in references.Finally,the parameters of horizontal displacement response of pile caused by tunnel excavation were analyzed.Moreover,the formula of maximum horizontal displacement of pile caused by tunnel excavation was put forward.The results show that the maximum horizontal displacement of pile is significantly affected by buried depth of tunnel,excavation size,and distance between tunnel and pile,and it is approximately linear with buried depth of tunnel.The maximum horizontal displacement of pile is less affected by the change of pile diameter.

关 键 词：隧道开挖 WINKLER地基 桩基水平变形 简化解析解 

分 类 号：TP028.8[自动化与计算机技术]