综放开采覆岩结构分析与支架工作阻力确定

Analysis on Overlying Strata Structure and Determination of Support Working Resistance in Fully Mechanized Caving Mining

针对仰斜综放工作面围岩控制难题,以瑞隆煤矿8101仰斜综放工作面为背景,建立倾斜岩梁力学模型对顶板破断位置进行分析,运用UDEC对采场围岩运移规律进行数值模拟,得出了8101仰斜综放工作面初次来压步距和支架合理工作阻力的计算公式。结果表明:仰斜综放条件下,上覆岩层受层向分力作用,有向采空区滑移的趋势,煤壁上方顶板受拉破断,破断位置相对靠后,支架稳定性降低,容易导致煤壁片帮、冒顶;通过现场实测,8101仰斜综放工作面初次来压步距为46 m,支架额定工作阻力9000 kN、最大工作阻力7932 kN,高于同等条件下水平工作面的来压步距和工作阻力。

Aiming at the surrounding rock control problem in upward inclined fully mechanized top coal caving face,taking 8101 upward inclined fully mechanized top coal caving working face of Ruilong Coal Mine as background,this paper established the mechanics model of simply supported rock beam to analyze the roof fracture position,conducted numerical simulation of surrounding rock movement by using UDEC,and obtained the calculation formula of first weighting interval and rational support working resistance in 8101 working face.Research showed that in the conditions of upward inclined fully mechanized top coal caving,overlying strata tended to slide toward the goaf due to component force in the direction of strata,roof above the coal wall fractured by tension force and the fracture position was relatively post,so the stability of support was decreased,which could cause coal wall spalling and roof fall easily;according to the field measurement results,the first weighting interval of 8101 working face was around 46 m,rated working resistance of the support was 9000 kN and the maximum working resistance was 7932 kN,which were larger than the interval of horizontal workface in the same geological condition.