双线隧道盾构施工对临近高层建筑物的影响分析

Research on the influence of twin shield tunnel construction on the adjacent high rise building

以北京市轨道交通6号线某区间盾构隧道工程实例为背景,针对双线盾构掘进先后通过临近高层建筑物的特殊情况,首先通过FLAC3D软件对该工程进行数值模拟,分析了先后盾构掘进两条平行隧道时地表最大沉降值的位置,以及盾构掘进与临近建筑物相互作用对地表沉降的影响;其次,对盾构掘进先后穿过高层建筑物的实测数据进行了分析,获得了双线盾构顺序穿越临近高层建筑物过程中地表沉降的变化规律;最后,分析了盾构施工对临近高层建筑物的影响.结果表明:在盾构面前方20 m作用的范围内,地表略微隆起,而盾构通过40 m后地表沉降基本稳定;后行隧道引起的地表沉降大于先行隧道引起的地表沉降;临近高层建筑物在隧道沉降槽影响范围内时,盾构施工对建筑物影响较大,而与双线隧道的先后施工顺序关系不大,数值计算和实测结果相符,对类似工程有一定的借鉴和指导意义.

The interactions between twin shield tunneling and the nearby high rise building were researched by numerical calculation and field monitoring, with the project of Beijing subway line 6 as the background. The place of maximum ground settlement when two parallel tunnels shield construction successive was assessed by using the software FLAC3D. And the influences of the interactions between twin shield tunneling and the nearby high rise building on the ground settlement were analyzed numerically. Further, the field instrumentation were presented and conducted during the tunnels -driven passing through the nearby high rise building successively, and the curves of ground settlement were obtained. The Influences of twin shield tunnel - driven successive on the adjacent structures were analyzed. The results show that the ground rises slightly at 20m ahead of the shield face, and the value of ground settlements is basically constant when the shield face passes cross - section 40m. The value of ground settlements caused by back shield tunneling is larger than it caused by the first shield tunneling. The tall building settlements are influenced greatly by shield construction when the tall building is in the range of tunnel settlement trough, and the settlements have little relationship with the construction sequence of the twin - tunnels. The results from field tests are consistent with numerical simulations, and it will potentially provide the knowledge for understanding tunneling undercrossing the existing tall buildings.