亭南煤矿东翼轨道大巷底鼓力学机制及控制技术

Floor heave mechanism and control technology for east rail roadway of Tingnan coal mine

为解决亭南煤矿东翼轨道大巷底鼓问题,采用现场调查、围岩物化成分分析、吸水软化试验和数值分析等方法,研究了亭南煤矿软岩巷道底鼓特征、影响因素和变形力学机制。结果表明:底鼓主要是由于巷道底板岩层岩性软弱膨胀性强,底板在无支护状态下成为巷道变形和应力释放的主要空间,巷道底角软岩在两帮应力传递作用下产生剪切塑性大变形,向底板中部挤压形成底鼓。提出了底板隔水、加固、控制变形的治理原则,采用混凝土反底拱+金属焊接网+底角管缝式锚杆的支护形式,对底板进行加固。通过现场监测和数值分析,表明新支护能够改善底板围岩受力状态,切断底角剪切滑移变形,有效控制巷道底鼓变形。

In order to solve the floor heave problems in the east rail roadway of Tingnan coal mine, using in-site survey, the physical and chemical composition analysis of surrounding rock, the water softening experiments and numerical analysis methods, the soft rock characteristics, influence factors and deformation mechanics mechanism have been researched. It is concluded that the main reason for the floor heave is mainly due to the strata lithology with weak floor but strong expansibility. Main deformation of roadway and stress release will appear in the bottom when there is no supporting. And the soft rocks in base angle will have large plastic deformation under the stress transfer from both sides of roadway, then extrudes to the center of the floor, forming the floor heave. Hence, corresponding control technology including impermeable base, strengthening, and deformation control is put forward by using the concrete arch-metal welding net-base angle seam pipe bolt support forms. Field monitoring and numerical analysis show that the new support can improve the floor rock mass condition and reduce the base shear deformation.