软弱围岩大断面隧道开挖面变形控制技术

软弱围岩隧道的开挖容易造成开挖面失稳坍塌、冒顶,以及地面与拱顶沉降过大等险情,所以需要对围岩和掌子面进行加固,以保证施工安全。以浙江野猪山隧道为工程背景,根据其掌子面采用长14 m、搭接长度为8 m的玻璃纤维锚杆加固后的实际监测,通过有限元模拟理论分析,得出掌子面挤出变形和拱顶沉降近似成线性关系。由此可以根据掌子面后方的拱顶沉降值预测掌子面前方的土质情况,以便及时采取加固措施。

Research on Deformation Control Technology of the Large Section Tunnel in Soft Rock

Various dangers and risks will occur in the excava-tion of soft surrounding rock tunnel,including the instability of excavation face,roof falling,large vault and ground settlement. To ensure the construction safety,the surrounding rock and tunnel face must be reinforced. In this paper,the Yezhushan Tunnel in Zhejiang Province is taken as the engineering back-ground,based on the actually measured data of the tunnel face, which is 14 m in length and reinforced by 8 m lap glass fiber anchor,then according to finite element simulation and theo-retical analysis,the vault settlement and the tunnel face extru-sion are detected close to a linear relationship. Therefore,it is possible to take reinforcement measures timely by forecasting the soil condition ahead according to the working face vault settlement in the rear.