基于滑移线场理论的巷道底鼓机理与防治技术研究

Study on floor heave mechanism and control technology of roadway based on slip line field theory

基于滑移线场理论对巷道底板岩层建立滑移线场模型,以山西焦煤回坡底煤矿1021巷为工程背景,研究了巷道非对称性底鼓机理,并提出了合理的底鼓防治技术。研究结果表明,巷道底板滑移线应力场中存在均匀应力场与非均匀应力场,从两帮往巷道中心线处,底板应力逐渐减小;底板滑移线主动区速度垂直向下,过渡区受主动区挤压而发生旋转并挤压被动区,被动区向上运动,从而产生巷道底鼓现象。回坡底煤矿1021巷由于受到孤岛煤柱应力集中作用,巷道两帮支承压力呈非对称分布,靠近煤柱一侧的高支承压力在底板形成滑移线场,其速度场方向指向远离煤柱一侧巷帮,因此1021巷底鼓现象具有明显的非对称性分布特征,远离煤柱一侧底鼓量较大。针对1021巷滑移型底鼓特征,采用单体锚索平行布置的非对称性支护进行巷道底鼓防治,现场应用效果良好。

Based on the slip line field theory,the slip line field model of roadway floor is established.Taking 1021 roadway of Huipodi coal mine in Shanxi Province as the engineering background,the mechanism of asymmetric floor heave of roadway is studied,and the reasonable prevention and control technology of floor heave is put forward.The results show that:There are uniform stress field and non-uniform stress field in the stress field of roadway floor slip line.From the two sides to the center line of the roadway,the floor stress decreases gradually;The velocity of the active zone of the floor slip line is vertical downward.The transition zone rotates and compresses the passive zone due to the extrusion of the active zone.The passive zone moves upward,resulting in floor heave.Due to the stress concentration of isolated pillar in Huipodi coal mine,the abutment pressure on both sides of the roadway is asymmetric.The abutment pressure near the coal pillar forms a slip line field on the floor,and the direction of the velocity field points to the side of the roadway far away from the pillar.Therefore,the floor heave of 1021 roadway is asymmetric,and the floor heave height at the side far away from the pillar is larger.According to the characteristics of sliding floor heave in 1021 roadway,asymmetric support with parallel arrangement of single anchor cable is adopted to prevent floor heave of roadway,and the application effect is good.