地铁盾构施工引起地表沉降特征与规律研究

Study on Characteristics and Laws of Surface Subsidence Caused by Subway Shield Construction

依托某市轨道交通九号线某区间工程,运用MidasGTS有限元分析软件建立数值分析模型,将整个隧道掘进过程分为10个施工阶段,计算施工过程中的地表沉降,分析不同掘进距离下地表的沉降量,并选取地表5个测点进行位移变形结果分析。结果表明:在隧道拱顶位置处产生沉降区域,在隧道拱底产生隆起现象,拱顶处的最大沉降值随着盾构掘进距离的增加而增大,盾构掘进到达地表监测点附近时,该监测点的地表沉降值变化速度较快。

Based on a certain section of the rail transit line 9 of a city,this paper uses Midas GTS finite element analysis software to establish a numerical analysis model,and divides the whole tunneling process into 10 construction stages to calculate the surface settlement during construction,and analyzes the surface of different tunneling distances.The settlement amount is selected,and the five points on the surface are selected for the displacement deformation analysis.The results show that the settlement area is generated at the position of the tunnel vault,and the bulging phenomenon occurs at the bottom of the tunnel.The maximum settlement value at the vault increases with the increase of the shield tunneling distance.When the shield tunneling reaches the surface monitoring point,the surface settlement value of the monitoring point changes rapidly.