摘要
以塔山矿8204-2工作面留设两段宽度连续变化的区段煤柱为背景,采用FLAC3D数值计算方法,对特厚煤层综放侧向应力分布规律和变宽度煤柱条件下掘采全过程的煤柱应力、巷道围岩位移和塑性区演化规律进行了三维全过程数值模拟。结果表明:采空区侧向应力降低区范围为0~15.41m,应力峰值位于距采空区边缘35.07m处;煤柱应力随着煤柱宽度的增加呈指数形式上升,具有"中间高,两边低"的特点;煤柱宽度小于20m时煤柱处于塑性状态,煤柱应力小于原岩应力,煤柱宽度为10m时巷道围岩稳定性最好。现场监测表明:巷道两帮和顶底板移近量在煤柱宽度为40m和35m时分别达到最大值,为691mm和885mm;煤柱宽度小于20 m时,巷道围岩变形量小于200 mm;采用"锚杆+锚索+JW钢带+组合锚索+金属网"联合支护方案能够有效维护巷道围岩稳定,满足安全生产要求。
Taking the variable-width pillar of 8204-2 working face in Tashan Coal Mine as the background,FLAC3D numerical calculation method was used for the three-dimensional whole process numerical simulation on the lateral stress distribution law of fully-mechanized caving in extra-thick coal seam,as well as the pillar stress,surrounding rock displacement and the evolution law of plastic zone in the whole excavation and mining process under the variable-width pillar.The results showed that the reduction area of lateral stress in goaf ranged from 0 m to 15.41 m,and the peak stress was located at 35.07 m away from the edge of goaf.The pillar stress increased exponentially with the increase of the width of coal pillar,which was characterized by"high in the middle and low on both sides".When the width of coal pillar was less than 20 m,the coal pillar was in a plastic state,the stress of coal pillar was less than that of original rock,and the surrounding rock of roadway was the best stable when the width of coal pillar was 10 m.Field monitoring showed that the maximum displacement in two sides or the roof and floor of roadway reached the maximum value of 691 mm and 885 mm when the width of coal pillar was 40 m and 35 m respectively,and the deformation of roadway surrounding rock was less than 200 mm when the width of coal pillar was less than 20 m.The combined support scheme of "bolt+anchor cable+JW steel belt+composite anchor cable+ metal mesh"can effectively maintain the stability of surrounding rock and meet the safety production requirements.
作者
陈祥祺
王伸
孙浩
童荣
CHEN Xiangqi;WANG Shen;SUN Hao;TONG Rong(School of Energy Science and Engineering,Henan Polytechnic University,Jiaozuo,Henan 454000,China;Shanxi Anmei Mining Design Engineering Co.,Ltd.Taiyuan,Shanxi 030006,China;Majialiang Coal Company Joint-stock by Datong Coal Mine Group and Zhejiang Provincial Energy Group Co.,Ltd,Shuozhou,Shanxi 036000,China)
出处
《矿业研究与开发》
CAS
北大核心
2020年第2期82-87,共6页
Mining Research and Development
基金
国家重点研发计划项目(2018YFC0604502)
关键词
特厚煤层
变宽度煤柱
应力分布
位移分布
围岩稳定性
Extra-thick coal seam
Variable-width coal pillar
Stress distribution
Displacement distribution
Stability of surrounding rock
