木寨岭隧道炭质板岩段大变形控制技术

Technology for Control of Large Deformation in Carbonaceous Slate Section of Muzhailing Tunnel

为解决高地应力炭质板岩隧道大变形的控制问题,以木寨岭隧道为例,从地质原因、设计原因、施工原因方面进行了大变形原因分析,通过选择合理的支护参数、采取保护围岩的施工理念,长锚杆、锁脚锚杆进行加强、优化断面形状、预留合理变形量并确定变形控制标准,适时进行支护加强、短台阶或超短台阶快开挖、快支护、快封闭和衬砌适时施作等综合施工技术,有效抑制了隧道大变形的发生。

Geological conditions,tunnel design and tunnel construction are analyzed in order to control the large deformation of the tunnel section in carbonaceous slate with high ground stress.Reasonable reinforcement parameters are selected,the surrounding rocks are protected,long bolts and foot-locking bolts are installed,the tunnel cross-section is optimized,reasonable deformation is allowed and deformation controlling standards are established.Construction technologies such as timely reinforcement strengthening,short or super-short bench excavation method,immediate reinforcement,immediate reinforcement structure closing and timely lining are adopted,which have brought the deformation under effective control.