过奥灰水断层的大断面巷道施工技术研究

Research on construction technology of large section roadway crossing Ordovician limestone water fault

为了解决济阳煤矿轨道石门过奥灰水断层时大断面巷道施工难题,根据工程类比,在确定初步支护方案的基础上,采用数值模拟方法对承压水威胁下大断面巷道的围岩稳定性进行了研究,优化了施工工艺和支护结构。结果表明:多层次的注浆加固增强了破碎围岩的整体性,减弱了开挖引起的围岩扰动;采用优化的支护方案后巷道顶板下沉量最大值为84 mm,且底板无突水威胁;结果证实以超前探测为先,以超前注浆和锚网梁为基础的喷棚注锚联合支护体系,能有效控制过奥灰水断层大断面巷道的围岩变形,充分发挥了围岩-支护共同作用,确保在过导水断层时大断面巷道施工安全。

In order to solve construction problems of large section roadway which crossing ordovician limestone water fault in Jiyang Coal Mine railway crosscut, the preliminary support scheme was determined firstly according to engineering analogy. On this basis, this paper analyzed the surrounding rock stability of large section roadway under the threat of confined water by numerical simulation method. Furthermore,the construction technology and supporting structure were optimized. The result showed that the multi-level grouting reinforcement enhanced the integrity of fractured surrounding rock and decreased the surrounding rock disturbance that caused by excavation. The maximum roof deformation was 84 mm and the floor would not have water inrush risk by using of the optimized supporting scheme. Therefore, the supporting system guiding by advanced detection and basing on the pre-grouting and the anchor net structure beam could effectively control surrounding rock deformation of large section roadway which crossing Ordovician limestone water fault. In this way, the supporting system gives full play to the interaction between rock and supports, and the construction safety of the large section roadway in water conductive fault was ensured.