厚煤层综放工作面区段煤柱内沿空掘巷小煤柱合理宽度研究

Study on the width of small pillar for gob-side entry driving in sectional coal pillar in fully mechanized top-coal caving face in thick seam

为解决布尔台矿区厚煤层矿压显现剧烈、巷道返修成本高等问题,以布尔台煤矿42203综放工作面沿空掘巷为研究背景,配合多种技术手段分析计算对沿空巷道的煤柱宽度留设进行研究。由理论、模拟得出的结果与现场测试的数据结果相印证,经极限平衡区的理论分析得到应力降低区在6.1~8.0 m范围内,根据数值计算结果分析煤柱宽度在3~7 m的变化过程中巷道围岩及煤柱内压力变化趋势,确定煤柱的合理留设宽度应大于等于5 m。并对邻近巷道进行了煤柱应力监测,分析现场实测结果,区段煤柱的应力降低区范围在5 m,综合考量巷道掘进片帮支护及采空区防漏风问题等安全因素,最终确定了厚煤层综放面区段煤柱内沿空掘巷小煤柱合理宽度为5 m。

In order to solve the severe ground pressure,high roadway repair cost and other problems in the thick coal seams of Buertai mining area,taking the gob-side entry driving of 42203 fully mechanized top-coal caving face in Buertai mining area as the research background,the width of retaining coal pillar for gob-side entry is studied with analysis and calculation of various technical means.According to the theoretical and simulation results and the field test data,the theoretical analysis of the limit equilibrium zone shows that the stress reduction zone is within the range of 6.1-8.0 m.According to the numerical calculation results,the pressure change trend in the surrounding rock of the roadway and the coal pillar during the change of the coal pillar width of 3-7 m is analyzed,and the reasonable width of the retaining coal pillar is determined to be greater than or equal to 5 m.The stress of coal pillar in the adjacent roadway was monitored,and the field measurement results were analyzed,which showed that the stress reduction area of the sectional coal pillar was within 5 m.Taking into account the safety factors such as the wall support of roadway excavation and the air leakage prevention in the goaf area,the reasonable width of the small coal pillar for the gob-side entry driving in the sectional coal pillar in fully mechanized top-coal caving face in thick seam is finally determined to be 5 m.