近距离条件下工作面开采大巷加固技术研究

Research on Reinforcement Technology of Mining Main Roadways in Working Faces under Close Distance Conditions

针对鹿洼煤矿33下01工作面开采时会对下部巷道产生扰动和破坏,影响下部巷道的使用问题,通过数值模拟结合弹性力学理论来分析近距离条件下工作面开采对下部巷道的影响,得出受到扰动影响的范围,提出对受扰动区域采取顶板锚索加底板注浆的补强支护方案。运用FLAC^(3D)软件对原支护方案与补强支护方案在围岩应力、巷道位移及塑性区三方面进行分析,结果显示补强支护后围岩应力变化不大,各剖切面应力峰值减小量不足1 MPa,由于等效支护应力远小于原岩应力,难以模拟影响效果。巷道顶板位移量减小稳定在40 mm左右;塑性区明显变小。根据现场观测测得巷道顶板位移量最终稳定在39 mm左右,因此补强支护方案可为距离工作面较近条件下的巷道的支护方法提供依据。

In view of the disturbance and damage caused to the lower roadway during the mining of the 33 lower 01 working face in Luwa Coal Mine,which affects the use of the lower roadway,numerical simulation combined with elastic mechanics theory is used to analyze the impact of working face mining on the lower roadway under close distance conditions.The range of disturbance impact is obtained,and a reinforcement support scheme of roof anchor cable and floor grouting is proposed for the disturbed area;use FLAC^(3D) software to analyze the original support scheme and reinforcement support scheme in three aspects:surrounding rock stress,roadway displacement,and plastic zone.The results show that there is little change in the stress of the surrounding rock after reinforcement and support,and the peak value of the stress of each cutting plane is reduced by less than 1 MPa.Due to the equivalent support stress being much smaller than the original rock stress,it is difficult to simulate the impact effect;the displacement amount of the roadway roof decreases and stabilizes at around 40 mm;the plastic zone is significantly decreased.According to the on-site observation,the displacement amount of the roadway roof ultimately stabilizes at around 39 mm.Therefore,the reinforcement support scheme can provide a basis for the support method of the roadway under the condition of near the working face.