盾构隧道近距离侧穿高层建筑的影响研究

 以北京地铁盾构区间隧道近距离侧穿高层建筑为背景，采用有限元计算和现场监测相结合的方法，对新建隧道施工所引起的邻近高层建筑物的结构沉降、基础倾斜进行深入研究，分析盾构到达建筑物之前、侧穿过程及离开后3个阶段建筑物的沉降、倾斜变化规律。计算结果表明，模型的竖向位移等值线在建筑物附近有一定的突变现象，而在距离建筑物一定的距离范围外，位移等值线又逐渐过渡为平滑曲线。现场实测结果表明，在盾构到达建筑物之前的临近影响区域内，建筑物向远离隧道方向一侧倾斜；盾构侧穿过程中，建筑物向邻近隧道方向一侧发生一定程度的倾斜，直至后期稳定。盾构到达监测断面前10 m，测点的上浮量达到了最大；盾构离开监测断面约60 m后，各测点的沉降速率明显减小，并开始趋于稳定。从数值模拟计算结果与现场监测情况来看，两者所反映的规律是相一致的，为今后类似工程提供借鉴。

STUDY OF IMPACT OF SHIELD TUNNELING SIDE-CROSSING ON ADJACENT HIGH BUILDINGS

Based on a certain constructing running shield tunnel of Beijing metro side-crossing close to a high-rise building,using the finite element method calculation model and site monitoring method,the foundation characteristics of the high-rise building affected by the constructing shield tunnel are studied. In different construction stages,the variations of the foundation settlement and inclination of the high building are analyzed. The simulation results show that stratum vertical displacement has a sudden change near the high-rise building. Away from the building in an enough distance,the displacement curve becomes flat. From site monitoring results,the high-rise building inclined to the direction away from the tunnel prior to the shield closing to the building,while the building inclined towards the tunnel during shield crossing. The settlements of the monitoring points reach the maximum value when the shield is 10.0 m away from the monitoring surface. However,the settlements declined significantly when the shield is more than 60.0 m from the monitoring surface,and finally becomes stable. The simulation and the site monitoring results agree well. The conclusion would be helpful for the future similar shield tunneling projects.