采场空间结构模型及相关动力灾害控制研究
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摘要
基于社会对煤炭行业安全生产的重视,煤矿灾害事故控制研究显得愈发重要,尤其现阶段煤矿灾害事故多发,安全形势愈发严峻。为了有效控制预防煤矿动力灾害事故,提出了采场空间结构模型;探讨了采场空间结构模型中应力分布和结构发育的力学特征,以及采动时上覆岩层的运动变化规律和矿压显现特征;以采场空间结构模型和采动应力孕育力学特征为基础,提出了采场顶板、巷道顶板控制、冲击地压、顶板水害,以及地表沉陷等煤矿灾害事故致灾条件及其控制措施,构建了相关采场灾害控制结构力学模型。建立的采场空间模型解释了"裂断拱"和"应力拱"结构演化规律以及采动应力与覆岩空间结构演化的相关性;指出了导水裂隙带高度与"裂断拱"高度范围基本一致,是顶板水害治理依据;建立了基于"应力拱"拱外岩梁下沉预测地表沉陷的方法;提出了对直接顶采取"给定载荷"控制方式,对基本顶采取"给定变形"和"限定变形"控制方式的支护方案;预测了冲击地压可能发生位置并提出了控制措施;提出了透水判据和不发生透水事故的合理工作面长度和开切眼位置的计算方法;建立了以开采工作面长度和覆岩裂断步距相关性为核心的采动沉陷模型,从力学的角度解释并计算分析了地表沉陷范围。实践证明,正确建立决策模型是实现煤矿灾害事故控制的基础,模型的建设有效实现了煤矿灾害事故控制从定性到定量的发展,可为煤矿灾害事故的有效预测和科学控制提供指导。
Based on the attention paid by the society to the safety of coal industry,the research on control of mining accident becomes more and more important,especially recently,the disaster accident occurs frequently,the safety form is more and more severe. Aiming at controlling dynamic disaster accidents in coal mine,a spatial structure model was modeled. The evolution of stress distribution and structure development in the spatial structure model,as well as the movement of overlying strata and the characteristics of strata behaviors during mining were revealed. Based on the spatial structure model and the mining-induced mechanical characteristics,the causing conditions of dynamic disaster accidents in coal mine,such as roof control,roadway roof control,rock burst,roof water inrush and surface subsidence,and related measures were analyzed,and the quantitative control-decision model of related dynamic disaster accidents was established.In the model,the evolution of"broken arch"and"stress arch"and the correlation between mining-induced stress and overlying strata movement were introduced. The height of the water flowing fractured zone is consistent with that of the"fractured arch",which is the basis of roof water inrush control,and the method of surface subsidence prediction based on the strata stress model of out-arch was established.The support project of"given load"mode for the direct roof and " given deformation" and " limited deformation" mode for the basic roof were proposed. The possible location of rock burst and the measures were put forward. The criterion of water inrush and the calculation method of the reasonable length of working face and the position of presplitting blasting were presented. A mining-induced subsidence model based on the correlation between working face length and overlying strata fracture length was established,and the range of subsidence was calculated by mechanics.The results showed that the correct establishment of control-decision model was the basis of controlling disaster accident in coal mine. The construction of model realized the development on the control of dynamic disaster accidents in coal mine from qualitative to quantitative and provided a guidance for effective forecast and control of dynamic disaster accidents in coal mine.
Based on the attention paid by the society to the safety of coal industry,the research on control of mining accident becomes more and more important,especially recently,the disaster accident occurs frequently,the safety form is more and more severe. Aiming at controlling dynamic disaster accidents in coal mine,a spatial structure model was modeled. The evolution of stress distribution and structure development in the spatial structure model,as well as the movement of overlying strata and the characteristics of strata behaviors during mining were revealed. Based on the spatial structure model and the mining-induced mechanical characteristics,the causing conditions of dynamic disaster accidents in coal mine,such as roof control,roadway roof control,rock burst,roof water inrush and surface subsidence,and related measures were analyzed,and the quantitative control-decision model of related dynamic disaster accidents was established.In the model,the evolution of"broken arch"and"stress arch"and the correlation between mining-induced stress and overlying strata movement were introduced. The height of the water flowing fractured zone is consistent with that of the"fractured arch",which is the basis of roof water inrush control,and the method of surface subsidence prediction based on the strata stress model of out-arch was established.The support project of"given load"mode for the direct roof and " given deformation" and " limited deformation" mode for the basic roof were proposed. The possible location of rock burst and the measures were put forward. The criterion of water inrush and the calculation method of the reasonable length of working face and the position of presplitting blasting were presented. A mining-induced subsidence model based on the correlation between working face length and overlying strata fracture length was established,and the range of subsidence was calculated by mechanics.The results showed that the correct establishment of control-decision model was the basis of controlling disaster accident in coal mine. The construction of model realized the development on the control of dynamic disaster accidents in coal mine from qualitative to quantitative and provided a guidance for effective forecast and control of dynamic disaster accidents in coal mine.
引文
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[3]宋振骐.实用矿山压力控制[M].中国矿业大学出版社,1988.
[4]宋振骐,蒋金泉.煤矿岩层控制的研究重点与方向[J].岩石力学与工程学报,1996,15(2):128-134.SONG Zhenqi,JIANG Jinquan. The current research situation and developing orientation of strata control in coal mine[J]. Chinese Journal of Rock Mechanics and Engineering,1996,15(2):128-134.
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[6]钱鸣高,朱德仁,王作棠.基本顶岩层断裂型式及对工作面来压的影响[J].中国矿业学院学报,1986,15(2):9-18.QIAN Minggao,ZHU Deren,WANG Zuotang.The fracture types of main roof and their effects on roof pressure in coal face[J].Journal of China University of Mining&Technology,1986,15(2):9-18.
[7]钱鸣高,缪协兴,何富连.采场“砌体梁”结构的关键块分析[J].煤炭学报,1994,19(6):557-563.QIAN Minggao,MIAO Xiexing,HE Fulian.Analysis of key block in the structure of voussoir beam in longwall mining[J]. Journal of China Coal Society,1994,19(6):557-563.
[8]王崇革,宋振骐,石永奎,等.近水平煤层开采上覆岩层运动与沉陷规律相关研究[J].岩土力学,2004,25(8):1343-1346.WANG Chongge,SONG Zhenqi,SHI Yongkui,et al. Study on the relation between stratum movement and subsidence of flat seam mining[J].Rock&Soil Mechanics,2004,25(8):1343-1346.
[9]姜福兴,宋振骐,宋扬.老顶的基本结构形式[J].岩石力学与工程学报,1993,12(4):366-379.JIANG Fuxing,SONG Zhenqi,SONG Yang.Basic structure forms of mine-roof[J].Chinese Journal of Rock Mechanics and Engineering,1993,12(4):366-379.
[10]姜福兴.采场覆岩空间结构观点及其应用研究[J].采矿与安全工程学报,2006,23(1):44-47.JIANG Fuxing. Viewpoint of spatial structures of overlying strata and its application in coal mine[J]. Journal of Mining&Safety Engineering,2006,23(1):44-47.
[11]文志杰,汤建泉,王洪彪.大采高采场力学模型及支架工作状态研究[J].煤炭学报,2011,36(S1):42-46.WEN Zhijie,TANG Jianquan,WANG Hongbiao. Study on mechanical model and hydraulic support working state in mining stope with large mining height[J].Journal of China Coal Society,2011,36(S1):42-46.
[12]黄庆享,张沛,董爱菊.浅埋煤层地表厚砂土层"拱梁"结构模型研究[J].岩土力学,2009,30(9):2722-2726.HUANG Qingxiang,ZHANG Pei,DONG Aiju. Mathematical model of"arch beam"of thick sandy soil layer movement in shallow seam[J]. Rock and Soil Mechanics,2009,30(9):2722-2726.
[13]左建平,孙运江,钱鸣高.厚松散层覆岩移动机理及“类双曲线”模型[J].煤炭学报,2017,42(6):1372-1379.ZUO Jianping,SUN Yunjiang,QIAN Minggao. Movement mechanism and analogous hyperbola model of overlying strata with thick alluvium[J].Journal of China Coal Society,2017,42(6):1372-1379.
[14]左建平,孙运江,王金涛,等.充分采动覆岩"类双曲线"破坏移动机理及模拟分析[J].采矿与安全工程学报,2018,35(1):71-77.ZUO Jianping,SUN Yunjiang,WANG Jintao,et al. Mechanical and numerical analysis of“analogous hyperbola”movement of overlying strata after full mining extraction[J].Journal of Mining&Safety Engineering,2018,35(1):71-77.
[15]于斌,朱卫兵,高瑞,等.特厚煤层综放开采大空间采场覆岩结构及作用机制[J].煤炭学报,2016,41(3):571-580.YU Bin,ZHU Weibing,GAO Rui,et al. Strata structure and its effect mechanism of large space stope for fully-mechanized sublevel caving mining of extremely thick coal seam[J]. Journal of China Coal Society,2016,41(3):571-580.
[16]朱卫兵,于斌.大空间采场远场关键层破断形式及其对矿压显现的影响[J].煤炭科学技术,2018,46(1):99-104.ZHU Weibing,YU Bin.Breakage form and its effect on strata behavior of far field key stratum in large space stope[J]. Coal Science and Technology,2018,46(1):99-104.
[17]谢广祥.综放工作面及其围岩宏观应力壳力学特征[J].煤炭学报,2005,30(3):309-313.XIE Guangxiang. Mechanical characteristics of fully mechanized top-coal caving face and surrounding rock stress shell[J].Journal of China Coal Society,2005,30(3):309-313.
[18] XIE Guangxiang,CHANG Jucai,YANG Ke. Investigations into stress shell characteristics of surrounding rock in fully mechanized top-coal caving face[J]. International Journal of Rock Mechanics and Mining Sciences,2009,46(1):172-181.
[19]谢广祥,李传明,王磊.巷道围岩应力壳力学特征与工程实践[J].煤炭学报,2016,41(12):2986-2992.XIE Guangxiang,LI Chuanming,WANG Lei. Mechanical characteristics and practical application on stress shell of roadway surrounding rock[J].Journal of China Coal Society,2016,41(12):2986-2992.
[20]谢广祥.采场围岩应力壳力学特征的岩性效应[J].煤炭学报,2013,38(1):44-49.XIE Guangxiang. Lithologic effect on the mechanical characteristics of mining-induced stress shell[J]. Journal of China Coal Society,2013,38(1):44-49.
[21]宋振骐,崔增娣,夏洪春,等.无煤柱矸石充填绿色安全高效开采模式及其工程理论基础研究[J].煤炭学报,2010,35(5):705-710.SONG Zhenqi, CUI Zengdi, XIA Hongchun, et al. The fundemental theoretial and engineering research on the green safe no coal pillar mining model by mainly using coal gangue backfill[J].Journal of China Coal Society,2010,35(5):705-710.
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