柠条塔煤矿大采高工作面切顶沿空留巷围岩变形机理研究

摘要

以柠条塔煤矿大采高工作面预裂切顶沿空留巷为工程背景,采用有限元数值模拟方法分析预裂切顶对沿空留巷围岩应力分布的影响.介绍了沿空留巷支护和爆破施工参数,根据围岩表面位移、顶板离层、恒阻锚索受力、液压支架工作阻力监测数据,分析了从开始留巷到变形稳定矿压显现规律.现场试验表明:切顶卸压自动成巷技术能够切断采动应力传递路径,明显降低了浅埋大采高工作面沿空留巷围岩受到的动压扰动,有效抑制了巷道围岩变形,成巷断面尺寸满足生产要求.%With the engineering background ofgob-side entry retaining of largemining height working surface in Ning-tiaota Coalmine by roof pre-splitting,the finite elementmethod were used to analyze the influence of roof pre-splitting to the stress distribution of surrounding rock duringgob-side entry retaining.The ofgob-side entry retaining supporting and blasting construction are introduced.According to themonitoring data of displacement and separation of surrounding rock,roof separa-tion,the stress of the constant resistance anchorage cable,work resistance of hydraulic support,the appearance law of surround-ing rock pressure from the beginning,deformation,stabilizing the pressure is analyzed.Field test shows that the entry retaining formed by roof cut and pressure releasing technique can cut off the transfer path ofmining stress,significantly reduce the dy-namic pressure disturbance on thegob-side entry retaining surrounding rock at shallow buried and largemining height working surface,and effectively restrain the deformation of surrounding rock.The roadway section size canmeet the requirements of pro-duction.