隧道开挖对既有受荷桩竖向承载特性的影响  

Influence of Tunnel Excavation on the Vertical Load Bearing Characteristics of Existing Piles

作　　者：靳军伟[1,2] 杨敏[3] 邓友生[4] 郭院成[1,2] JIN Junwei YANG Min DENG Yousheng GUO Yuancheng(School of Civil Engineering, Zhengzhou University, Zhengzhou, China, 450001 Laboratory of Underground Engineering Safety and Quality Control of Henan Province, Zhengzhou, China,450001 Department of Geotech- nical Engineering, Tongji University, Shanghai, China, 200092 School of Civil Engineering ＆ Architecture, Hu- bei University of Technology, Wuhan, China ,430068)

机构地区：[1]郑州大学土木工程学院,河南郑州450001 [2]地下工程安全与质量控制河南省工程实验室,河南郑州450001 [3]同济大学地下建筑与工程系,上海200092 [4]湖北工业大学土木工程与建筑学院,湖北武汉430068

出　　处：《沈阳建筑大学学报（自然科学版）》2016年第5期820-826,共7页Journal of Shenyang Jianzhu University：Natural Science

基　　金：国家自然科学基金项目(41172248);郑州大学青年教师启动基金项目(51090100)

摘　　要：目的研究黏土中隧道开挖对既有受荷单桩基础竖向承载特性的影响,分析桩基础竖向承载特性变化.方法采用位移控制有限元方法模拟隧道开挖对桩基础竖向承载特性的影响.结果隧道开挖导致既有桩基础发生显著沉降,但在不同初始荷载水平作用下,对单桩极限承载力最终值影响较小.轴力增量呈S型分布,在桩基础下部产生摩阻力,上部产生负摩阻力;桩端土体中超孔隙水压力在隧道开挖过程中逐渐增大.结论隧道开挖对既有受荷桩竖向承载力最终值影响不大,但是对桩身沉降影响很大.城市地铁隧道开挖对既有建筑桩基础承载特性影响的研究成果,为盾构施工后桩基础承载力分析提供参考.The purpose of this paper is to study the influence of pile bearing capacity induced by nearby tunnelling in clay. The deformation control finite element method is used to simulate the tunnel excavation and the pile bearing capacity and settlement is analyzed during the simulation. The results show that tunnel excavation can induce a remarkable pile settlement, but the finite load capacity is almost not changed. Increment of axial force of the pile distribute like S form. Tunnel- ling causes changes of pile side friction, and negative friction can be found near ground. The excess pore pressure increases during the excavation. Hence, influence of pile settlement induced by near- by tunnelling is more serious than that of bearing capacity. The results give the researches some reference values on bearing capacity influence of pile foundation induced by tunnelling in the city.

关 键 词：地铁隧道开挖 位移控制有限元 单桩竖向承载力 沉降 

分 类 号：TU47[建筑科学—结构工程]