基于流固耦合作用的太原砂卵石层盾构隧道变形特性分析  

Deformation Characteristics Analysis of Shield Tunnel in Taiyuan Sand and Pebble Layer Based on Fluid-Solid Coupling

作　　者：甄正[1] 葛忻声[1] 张军 ZHEN Zheng;GE Xin-Sheng;ZHANG Jun(College of Civil Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Shanxi Transportation Research Institute Group Co.Ltd.,Taiyuan 030032,China)

机构地区：[1]太原理工大学土木工程学院,太原市030024 [2]山西交通科学研究院集团有限公司,太原市030032

出　　处：《公路》2021年第4期361-367,共7页Highway

摘　　要：依托太原铁路枢纽新建西南环线勘察资料,结合盾构施工中实际的监测资料,利用Plaxis软件模拟分析了考虑与不考虑流固耦合作用下盾构机在砂卵石层中的掘进情况,研究了盾构施工扰动引起的地表沉降、隧道周围主应力和孔隙水压力变化的规律。研究结果表明:考虑耦合作用下的地表沉降范围比不考虑耦合作用广,与实际情况接近,砂卵石地区的沉降槽系数约为15m;考虑耦合与不耦合作用下拱顶和拱底都出现斑点状的低应力集中区域,而考虑耦合作用下的拱顶处最大主应力场呈现漏斗状,耦合主要影响最大主应力分布;考虑耦合作用下拱腰的孔隙水压力呈"勺子"状,并在隧道周围产生了负值的超孔隙水压力,孔隙水压力主要在拱腰和拱底处变化。Combined with the survey data of the newly-built Taiyuan Southwest Ring Road and the actual monitoring data in shield construction,in the paper Plaxis software is used to simulate and analyze the situation of shield machine tunneling in sandy pebble layer when with and without considering fluidsolid coupling,and the variation laws of surface settlement,principal stress around tunnel and pore water pressure caused by shield construction disturbance are studied.The results show that:the range of surface subsidence considering coupling effect is wider than that without considering coupling effect,which is close to the actual situation.The subsidence trough coefficient in sandy pebble area is about 15 m;considering coupling and uncoupling,both the vault and the arch bottom have spotted low stress concentration areas,while considering coupling,the maximum principal stress field at the vault presents funnel shape,and coupling mainly affects the distribution of maximum principal stress.Considering that the pore water pressure of the arch waist is"spoon"under the coupling action,and negative excess pore water pressure is generated around the tunnel,the waterproof measures between the arch roof and the arch waist of the tunnel are strengthened.Besides,pore water pressure mainly changes at the arch waist and arch bottom.

关 键 词：盾构隧道 流固耦合 地表沉降 主应力 孔隙水压力 

分 类 号：U455.43[建筑科学—桥梁与隧道工程]