某地铁车站深基坑施工监测分析

以某地铁车站深基坑为背景,对施工期间的围护墙体水平位移、墙体沉降、地下水位、钢支撑轴力和立柱隆沉等监测数据进行分析。实测结果表明:基坑开挖到基底时,坑壁2/3深度处水平变位最大,达7.57 mm;钢支撑轴力远小于设计值,有较大的空间可以利用,可对设计进行优化;地下水位的变化说明车站的施工未对周围环境造成太大影响;坑底最大隆起值为13.8 mm,墙体最大水平变位7.5 mm,地表沉降最大值为-2.4 mm,均远小于警戒值。监测数据及分析表明,基坑采用地下连续墙加3道支撑的支护方案是安全可行的。

CONSTRUCTION MONITORING ANALYSIS OF AN DEEP EXCAVATION OF A SUBWAY STATION

It was analyzed the monitoring data of the deep excavation of a subway station in Zhengzhou,such as horizontal displacement of retaining wall,axial force of steel struts,surface settlements,etc. The results show that the excavation to the basement,the maximum horizontal displacement at 2 /3 depth of the pit wall is up to 7. 57 mm.And the monitoring value of the steel support axial force is far smaller than the design value,so the design can be optimized Changes in groundwater level shows that the station construction has not too much impact on the surrounding environment,the biggest bottom uplift value is 13. 8 mm,wall maximum horizontal displacement is 7. 5 mm,maximum surface subsidence is 2. 4 mm,which are far less than alert values,Monitoring data and the analysis show that,the support scheme of foundation pit with underground diaphragm with three-row support support is safe and feasible.