西北黄土地区地铁深基坑工程监测的关键技术

Study for Key Technology of Metro Deep Foundation Pit Monitor in Loess Region of Northwest China

根据西北黄土地区第一条地铁——西安地铁近四年地铁基坑工程的监测经验,提出了基坑工程监测的主要内容、作用及其常用监测手段,介绍了轴力监测关键技术;测斜仪量测墙体位移关键技术;地裂缝段地表监测点布设的关键技术;盾构地表监测作用、监测项目、地层移动特征;监测报警注意事项。其中着重分析了黄土地区常用的内支撑形式——钢支撑监测的注意事项及常见异常测量数据的出现原因,提出温度对其测量结果的影响不可忽略。

This paper puts forward main content, the effect, common monitoring means of deep pit engineering based on four years experience of the first metro deep foundation pit monitor in the loess region of Northwest China. This paper intro- duces the key technology in axial force monitoring, displacement measurement by inclinometer, the layout principles of ground fissures surface points. This paper introduces the monitoring action and monitoring items of shield tunnel. Formation moving characteristics under shield construction and points for attention in monitoring alarm are put forward. This paper puts forward emphatically analyses points for attention and cause of abnormity in rigid supporting axial force monitoring. It is the most com- mon method of internal bracing in the loess region of Northwest China. This paper puts forward that, the influence of temperature action on rigid supporting axial force monitoring can not be neglected.