Abstract:The rupture and movement scope of overlying strata increase sharply since the high strength and rapid exploitation of the longwall mining faces;and the spatial structure formed by fractured strata becomes much more complex. The overlying strata would move and interact coordinately when more workfaces exist;hence leading to mining dynamic disasters that defined as spatial structure instability in this paper. Based on the boundary conditions,three basic forms that named OX,F and T structure are identified,respectively. The OX-F-T evolution of the overlying strata is presented that the O-X fracture is the elemental structure of overlying strata and also the boundary of adjacent workface,one side is OX constitute F structure,and both side with OX is T structure. The characteristics and detailed classifications for each type are elaborated. The microseismic system is used for on-site monitoring,single,double and isolated workfaces that represent the OX,F and T structure are selected respectively to research the distribution rules of seismic events;the results confirmed the OX-F-T spatial structure feature. At last,specialized methods are proposed targeted to workfaces with different spatial structures. The research results provide theoretical guidance for dynamic disaster prevention and control in coal mines.
[1] 王家臣,富 强. 低位综放开采顶煤放出的散体介质流理论与应用[J]. 煤炭学报,2002,27(4):337–341.(WANG Jiachen,FU Qiang. The loose medium flow field theory and its application to the longwall top-coal caving[J]. Journal of China Coal Society,2002,27(4):337–341.(in Chinese))
[2] 闫少宏,尹希文. 大采高综放开采几个理论问题的研究[J]. 煤炭学报,2008,33(5):481–484.(YAN Shaohong,YIN Xiwen. Discussing about the main theoretical problems of longwall with top coal caving[J]. Journal of China Coal Society,2008,33(5):481–484.(in Chinese))
[3] 柏建彪. 综放沿空掘巷围岩稳定性原理及控制技术研究[博士学位论文][D]. 徐州:中国矿业大学,2005.(BAI Jianbiao. Study on stability and control of roadway driven along next goaf for fully-mechanized top-coal caving face[Ph. D. Thesis][D]. Xuzhou:China University of Mining and Technology,2005.(in Chinese))
[4] 蒋金泉,张开智. 综放开采矿震的成因及防治对策[J]. 岩石力学与工程学报,2006,25(增1):3 277–3 282.(JIANG Jinquan,ZHANG Kaizhi. Cause and control method of mine earthquake in fully mechanized top coal caving mining[J]. Chinese Journal of Rock Mechanics and Engineering,2006,25(Supp.1):3 277–3 282.(in Chinese))
[5] 姜福兴,XUN L,杨淑华. 采场覆岩空间破裂与采动应力场的微震探测研究[J]. 岩土工程学报,2003,25(1):23–25.(JIANG Fuxing,XUN L,YANG Shuhua. Study on microseismic monitoring for spatial structure of overlying strata and mining pressure field in longwall face[J]. Chinese Journal of Geotechnical Engineering,2003,25(1):23–25.(in Chinese))
[6] 贺 虎,窦林名,巩思园,等. 覆岩关键层运动诱发冲击的规律研究[J]. 岩土工程学报,2010,32(8):1 261–1 265.(HE Hu,DOU Linming,GONG Siyuan,et al. Rock burst rules induced by cracking of overlying key stratum[J]. Chinese Journal of Geotechnical Engineering,2010,32(8):1 261–1 265.(in Chinese))
[7] DOU L M,LU C P,MU Z L,et al. Prevention and forecasting of rock burst hazards in coal mines[J]. Mining Science and Technology,2009,19(5):585–591.
[8] 窦林名,赵从国,杨思光,等. 煤矿开采冲击矿压灾害防治[M]. 徐州:中国矿业大学出版社,2006:7–10.(DOU Linming,ZHAO Congguo,YANG Siguang,et al. Prevention and control of rock burst in coal mine[M]. Xuzhou:China University of Mining and Technology Press,2006:7–10.(in Chinese))
[9] 钱鸣高,缪协兴,许家林,等. 岩层控制的关键层理论[M]. 徐州:中国矿业大学出版社,2000:85–88.(QIAN Minggao,MIAO Xiexing,XU Jialin,et al. Key strata theory in ground control[M]. Xuzhou:China University of Mining and Technology Press,2000:85–88.(in Chinese))
[10] 钱鸣高,石平五. 矿山压力与岩层控制[M]. 徐州:中国矿业大学出版社,2003:91–96.(QIAN Minggao,SHI Pingwu. Ground pressure and strata control[M]. Xuzhou:China University of Mining and Technology Press,2003:91–96.(in Chinese))
[11] 史 红,姜福兴. 采场上覆大厚度坚硬岩层破断规律的力学分析[J]. 岩石力学与工程学报,2004,23(18):3 066–3 069.(SHI Hong,JIANG Fuxing. Mechanical analysis of rupture regularity of hard and massive overlying strata of longwall face[J]. Chinese Journal of Rock Mechanics and Engineering,2004,23(18):3 066–3 069.(in Chinese))
[12] 姜福兴,张兴民,杨淑华,等. 长壁采场覆岩空间结构探讨[J]. 岩石力学与工程学报,2006,25(3):979–984.(JIANG Fuxing,ZHANG Xingmin,YANG Shuhua,et al. Discussion on overlying strata spatial structures of longwall in coal mine[J]. Chinese Journal of Rock Mechanics and Engineering,2006,25(3):979–984.(in Chinese))
[13] 谢和平,段法兵,周宏伟,等. 条带煤柱稳定性理论与分析方法研究进展[J]. 中国矿业,1998,7(5):37–41.(XIE Heping,DUAN Fabing,ZHOU Hongwei,et al. Recent developments of theory and analysis methods of strip pillar stability[J]. China Mining Magazine, 1998,7(5):37–41.(in Chinese))
[14] 窦林名,何 烨,张卫东. 孤岛工作面冲击矿压危险及其控制[J]. 岩石力学与工程学报,2003,22(11):1 866–1 869.(DOU Linming,HE Ye,ZHANG Weidong. Hazards of rock burst in island coal face and its control[J]. Chinese Journal of Rock Mechanics and Engineering,2003,22(11):1 866–1 869.(in Chinese))