TBM施工条件下隧道净空位移监测

MONITORING OF TUNNEL CLEARANCE DISPLACEMENTS UNDER CONDITION OF TBM CONSTRUCTION

以辽宁大伙房输水工程为背景,介绍TBM施工条件下隧道净空位移监测技术。根据试验,提出一种激光准直TBM隧道净空位移监测方法,它利用开敞式掘进机与隧道周边之间的纵向通视空间,通过对拱顶和两侧边墙三点位应用激光准直法来实现,从而解决TBM施工中现有监测方法难以有效实施净空位移监测的难题。同时,研制出SWL–I型TBM隧道激光位移监测系统,具有满意的量测精度和简便的操作特性,已在该工程Robbins和Wirth两种开敞式掘进机施工环境中得到应用验证,并获得掘进机刀盘尾部拱顶和两侧边墙围岩净空位移的变化特性曲线,实现了TBM施工条件下的净空位移监测。

Taking Dahuofang Water Transfer Project in Liaoning Province as background, the monitoring technique of tunnel clearance displacements in the tunnel boring machine（TBM） bid segments is introduced under condition of TBM construction. Based on the tests, a monitoring method of TBM tunnel clearance displacements with laser collimation is proposed. It comes true by utilizing the longitudinal intervisible space between the boring machine and tunnel profile and using the laser collimation method to the three measuring points on the crown and two sidewalls. Thereby, the problem that the tunnel clearance displacement under condition of TBM construction is difficult to be obtained with existing monitoring methods can be resolved. Also, the SWL- I tunnel laser displacement monitoring system with satisfying measuring precision, simple and easy-to-operate characteristics is developed. The system has been applied and verified in the construction of Dahuofang Water Transfer Project by use of Robbins and Wirth＇s open TBMs. The displacement characteristic curves of surrounding rock in the tunnel crown and both sidewalls at the end of the machine cutterhead are obtained firstly; and the monitoring of tunnel clearance displacements under condition of TBM construction has been realized.