摘要
以青岛地铁8号线青沧区间左线下穿3号线暗挖段ZDK47+540.430~ZDK47+670段为背景,采用悬臂掘进机开挖环形台阶法施工.通过收集现场前期监测数据,运用Origin 8.0软件,绘制洞内净空收敛和拱顶沉降的历时变化曲线,并结合隧道区间开挖上下错开距离进行对比分析.结果表明:隧道上方地铁运营对洞内围岩竖向位移影响尤为明显,对洞内水平位移影响较小;经监测发现,上、下台阶在交替开挖过程中会对洞内围岩稳定性产生影响,在最小工作面为15 m(悬臂掘进机的最小工作面)的基础上,为很好地兼顾施工机械的便利操作和洞内掌子面的安全稳定,上下台阶错开距离宜控制在3 B(B为隧道洞宽)左右.
Taking the ZDK47+540.430~ZDK47+670 segment of the left line underground excavation section of Line 8 Qing Cang section passing through Qingdao Metro Line 3 as the background,this study adopts the circular step excavation method and uses the cantilever road header to excavate.By collecting the monitoring data of the site in the early stage,and using the Origin 8.0 software,the diachronic curve of the clearance convergence and vault settlement is drawn,and a comparative analysis is carried out in terms of the distance between the upper and lower staggered excavation of the tunnel section.The results show that the subway operation above the tunnel has a significant impact on the vertical displacement of the surrounding rock,and has little effect on the horizontal displacement of the tunnel.It is found through monitoring that the stability of the surrounding rock is affected during the alternate excavation process in the upper and lower steps.The impact is on the basis of the minimum working surface of 15 m(the minimum working surface of the cantilever road header).In order to give a balanced consideration to the convenient operation of the construction machinery and the safety and stability of the tunnel face,the staggered distance between the upper and lower steps should be controlled to around 3 B(B is the tunnel width).
作者
李阳
时伟
卢志强
周运刚
LI Yang;SHI Wei;LU Zhi-qiang;ZHOU Yun-gang(School of Civil Engineering,Qingdao University of Technology,Qingdao 266033,China;Shanghai Tongshi Science and Technology Co.,Ltd.,Shanghai 201203,China)
出处
《青岛理工大学学报》
CAS
2020年第1期7-13,共7页
Journal of Qingdao University of Technology
关键词
暗挖下穿
拱顶沉降
净空收敛
错开距离
crossing underneath
vault settlement
clearance convergence
staggered distance
