上海地铁M8线某车站基坑开挖变形特征分析

基坑变形大小和变化规律不仅关系到基坑本身的安全,也关系到周围建筑物及地下管线的安全.上海轨道交通M8线某车站位于上海市市中心,周围建筑物和管线密集,且基坑紧贴地铁一号线车站,对环境保护要求非常高.根据基坑围护结构监测数据,分析了围护墙体的变形特征,发现基坑在开挖过程中其变形符合时空效应规律,基坑变形大小和速率与基坑暴露时间和每次开挖方量密切相关,在开挖过程中要特别注意支撑架设的及时性和挖土工艺.发现车站标准段与端头井水平变形特征有所差异,端头井最大水平位移相对标准段较小,这与端头井采用满膛加固的原因有关.最后分析了基坑周围建筑物的沉降特征.

Research of deformation laws of shanghai metro line 8station pit

One station of Shanghai Metro Line 8 is next to the station of Metro Line 1 and quite near to other buildings.Through gathering and analyzing a great lot of field data and making use of forward and back analysis methods, we find out deformation laws of pit foundation and brings forward the conclusion of time-space effect on the basis of quantization and comparison The deformation of pit is closely correlative with excavation speed and exposure time. So it is very important to pay attention to support the pit in time and excavation techniques. It is different between station and end pile for their reinforce measure.