采动巷道围岩非均匀变形特征及稳定性控制技术研究

受到原岩应力与采动应力叠加影响的巷道会产生非均匀变形,甚至发现顶板事故,采动巷道围岩稳定性控制是实现矿井安全高效开采的关键。针对长岭一号煤矿152106工作面轨道巷受到采动影响变形严重的问题,采用现场监测、数值模拟等研究方法,分析了采动巷道围岩变形特征及塑性区演化规律。结果表明：在采动影响下,巷道围岩变形呈非均匀特征,工作面前方巷道围岩变形量小于工作面后方,巷道煤柱侧变形量大于煤壁侧,顶板出现离层并且靠近煤柱侧底鼓量更大,局部可达400mm|工作面前方最大主应力、主应力比值、塑性区范围均小于工作面后方,塑性区呈椭圆形分布,巷道围岩位移量与塑性区范围具有一致性。据此提出了补强支护方案,即顶板补打锚索、煤柱对穿锚索及打设单体液压支柱,现场试验结果表明轨道巷煤柱帮变形减少了65%,巷道底鼓量260mm,工程应用效果较好。

Non-uniform deformation characteristics and stability control of mining roadway surrounding rock

The roadway affected by the in-situ stress and mining stress will produce non-uniform deformation, and even cause roof accidents. The stability control of surrounding rock of mining roadway is the key to realize the safe and efficient production. In view of the serious deformation of 152106 working face track roadway under the influence of mining in Changling No. 1 Coal Mine, field monitoring, numerical simulation and other research methods are used to analyze the deformation characteristics of surrounding rock and the evolution law of plastic zone of mining roadway. The results show that under the influence of mining, the deformation of roadway surrounding rock is non-uniform. The deformation of roadway surrounding rock in front of the working face is smaller than that in the back of the working face, the deformation of roadway pillar side is larger than that in the coal wall side, the roof is separated and the floor heave near the pillar side are larger, and locally up to 400mm. The maximum principal stress, the ratio of principal stress and the range of plastic zone in front of the working face are all smaller than those behind the working face, plastic zone is elliptic in shape, and the displacement of surrounding rock is consistent with the range of plastic zone. Based on this, the reinforcement support scheme is put forward, namely the roof and the coal pillar is reinforced with anchor cable and two-ended cable respectively, and the single hydraulic prop is set up. The field test results show that the deformation of pillar wall of the track roadway is reduced by 65%, and the roadway floor heave is 260mm, so good engineering application effect has been obtained.