双圆盾构隧道开挖引起邻近桩土位移试验研究  

Experimental Research on Double-O-Tube Shield Tunneling-Induced Adjacent Pile-Soil Displacement

作　　者：朱语聪 曾彬 叶四桥[1,2] 何磊 张立舟 Zhu Yucong;Zeng Bin;Ye Siqiao;He Lei;Zhang Lizhou(School of River and Ocean Engineering,Chongqing Jiaotong University,Chongqing 400074,P.R.China;Key Laboratory of Geological Hazards Mitigation for Mountainous Highway and Waterway,Chongqing Municipal Education Commission,Chongqing 400074,P.R.China;Chongqing Survey Institute,Chongqing 401121,P.R.China)

机构地区：[1]重庆交通大学河海学院,重庆400074 [2]山区公路水运交通地质减灾重庆市高校市级重点实验室,重庆400074 [3]重庆市勘测院,重庆401121

出　　处：《地下空间与工程学报》2023年第5期1504-1514,共11页Chinese Journal of Underground Space and Engineering

基　　金：中国博士后科学基金(2022M722712);重庆市自然科学基金(CSTB2023NSCQ-MSX0847);重庆市教委科学技术研究青年项目(KJQN202200719)。

摘　　要：双圆盾构隧道具有比单圆盾构隧道复杂得多的断面形式,由此引起的邻近土体和桩的位移特征比较复杂。采用自主设计研发的双圆盾构隧道透明土试验装置,通过分析隧道上方水平与竖直地层位移特征、隧道周围土体位移云图、桩及桩周土体位移规律,系统探究不同埋深的双圆盾构隧道掘进引起的邻近桩-土位移响应。结果表明:随着双圆盾构隧道埋深增加,最大地表横向位移先增大后减小,最大地表沉降逐渐降低,隧道顶部沉降逐渐增加,沉降曲线形状由地表到隧道顶部呈“U-V-W”形的逐渐过渡;地表横向位移和隧道纵断面上方沉降分别在盾尾经过监测面(桩轴线位置)0.7D和0.6D(D为隧道开挖直径)后达到峰值并趋于稳定;随着覆土深度的增加,竖向地层的横向位移先减小后增大再减小,横向位移峰值位于隧道中心同一水平处,而土体沉降呈先慢后快地减小变化;邻近桩基对桩侧土体位移具有限制作用,桩基整体发生下沉和偏转;埋深为1.5D时的桩-土位移明显大于埋深为1.0D和2.0D时的桩-土位移。Due to the complexities of the cross-sectional form of double-O-tube(DOT)shield tunnels larger than circular shield tunnels,the resulting displacement characteristics of the adjacent soils and piles are relatively complex.This paper designs and develops a DOT shield tunnel transparent soil model test device.The displacement characteristics of horizontal and vertical soil layers above the tunnel,soil displacement contour maps around the tunnel,pile and soil displacement patterns around the piles are carried out to systematically investigate pile-soil displacement response caused by the DOT shield tunneling under different buried depths.The results show that:with the depth of the DOT shield tunnel increases,the maximum horizontal displacement of the surface increases and then decreases,the maximum surface settlement gradually decreases and the settlement at the top of the tunnel gradually increases.In addition,settlement curves gradually transform from the surface to the top of the DOT tunnel in a"U-V-W"shape.Horizontal displacements of the surface and settlements above the longitudinal section of the DOT tunnel peck and plateau after the shield tail passes the monitoring face(at the pile axis)at 0.7D and 0.6D(D is the diameter of the tunnel excavation),respectively.With the increase of the soil depth,horizontal displacements of vertical soil layers decrease,then increase and finally decrease,maximum horizontal displacements are located at the horizontal axis of the DOT tunnel,while settlements decrease slowly first and fast afterward.The adjacent pile limits soil displacements beside the pile,and the pile occurs overall settlement and deflection.The pile-soil displacements for a tunnel buried depth of 1.5D are obviously larger than those for tunnel buried depths of 1.0D and 2.0D.

关 键 词：双圆盾构隧道 透明土 土体损失 桩-土位移 模型试验 

分 类 号：U458[建筑科学—桥梁与隧道工程]