深部硬岩巷道围岩变形特征及其控制技术

Deformation Characteristics and Control Technology of Surrounding Rock in Deep Hard Rock Tunnel

为探究深部硬岩巷道在复杂地质条件下的变形特性,本文以纱岭金矿-1465 m深部主巷为工程背景,通过现场工程地质调查获取了围岩的结构面信息,并计算岩体中的优势节理组和RQD值,对其地质环境和岩体条件进行概述。采用振弦式微应变传感器对调查点巷道的围岩进行监测,提取巷道顶板和两帮距离揭露面不同深度围岩随时间的变形数据,总结和分析深部硬岩巷道在高应力和复杂地质条件下围岩的变形特征。基于岩体条件和围岩变形规律提出该巷道宜采用“树脂锚杆+金属网+喷射混凝土”支护,并应用有限元数值模拟软件Phase 2对该支护方式进行有效性检验,结果表明,采用该支护方式可有效降低围岩的变形量。

In order to explore the deformation characteristics of the deep hard rock tunnel under the complex geological conditions,this paper takes the deep main tunnel of-1465 m in the Shaling Gold Mine as the engineering background,obtains the structural plane information of the surrounding rock through the field engineering geological survey,calculates the dominant joint group and RQD in the rock mass,and summarizes its geological environment and rock mass conditions.The vibrating wire microstrain sensor is used to monitor the surrounding rock of the surveyed tunnel.The deformation data of the surrounding rock with time at different depth exposed in various directions of the tunnel are extracted.The deformation characteristics of the surrounding rock of the deep hard rock tunnel under high stress and complex geological conditions are summarized and analyzed.Based on the rock mass conditions and the deformation characteristics of the surrounding rock,it is proposed that the tunnel should be supported by"resin bolt+metal mesh+shotcrete",and the finite element numerical simulation software Phase 2 is used to test the effectiveness of the support mode.The results show that the support mode can effectively reduce the deformation of the surrounding rock.