构造应力影响下软岩硐室底鼓机理及控制研究

Study on Mechanism and Control of Floor Heave of Soft Rock Chamber under Influence of Tectonic Stress

针对桑北煤矿采区水泵房强烈底鼓难题,通过现场调研、理论计算及数值模拟等方法,总结了水泵房底鼓特征,揭示了底鼓诱发机理,确定了底鼓控制的基本原则,以锚注支护为核心,提出了“浅层开挖+分层疏水+底板锚注+浇筑回填”的底鼓控制技术,并解析了底鼓控制关键参数,在此基础上开发了“硐室断面扩修+底板锚注支护+顶帮补强支护”底鼓控制方案。工业性试验结果显示:硐室围岩变形在20 d内趋于稳定,最大底鼓量仅为28 mm,顶板下沉量与两帮移近量均小于100 mm,满足了矿井的生产要求,为类似条件下硐室治理提供了参考。

Aiming at the problem of strong floor heave of water pump house in mining area of Sangbei coal mine,through field investigation,theoretical calculation and numerical simulation,summarizes the deformation characteristics of floor heave of water pump house,reveals the inducing mechanism of floor heave,determines the basic principle of floor heave control,and puts forward the floor heave control technology of"shallow excavation+layered drainage+floor bolting+pouring and backfilling"with bolt grouting support as the core,the key parameters of floor heave control are analyzed,and on this basis,the floor heave control scheme of"chamber section expansion+floor anchor grouting support+top wall reinforcement support"is developed.The industrial test results show that the deformation of the surrounding rock of the chamber tends to be stable within 20 days,the maximum bottom heave is only28 mm,and the displacement of the top and wall on both sides is less than 100 mm,which meets the production requirements of the mine and provides a reference for the treatment of the chamber under similar conditions.