沿空留巷底板变形力学分析及底臌防控
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摘要
上覆岩层垮落产生的动载荷通过巷帮煤体、巷内支护体以及巷旁支护体传递给底板,造成工作面后方一段距离的沿空留巷底臌变形加剧。为了控制上覆岩层垮落引起的底臌变形,在分析沿空留巷力学环境的基础上,建立底板力学模型,计算出沿空留巷煤帮弹性压缩区、塑性区、破裂区的宽度,以及煤帮对底板的作用力。应用关键层理论,确定顶板硬岩层位置及其破断顺序,以及垮断极限层的层位;采用顶板载荷条带分割法,计算出巷旁支护体对底板的作用力,并引入等效载荷的概念,构建底板等效载荷分布力学模型,将沿空留巷底臌与上覆岩层垮落紧密联系起来,分析上覆岩层垮落对底板的受力及变形影响,推导出底臌变形计算式。研究结果表明:上覆岩层垮落引起的底臌主要是由于塑性区煤体和巷旁支护体下方底板岩层高应力压剪破坏,以及巷道底板和采空区底板在强卸荷条件的拉伸破坏共同影响造成的。基于此,提出了降低塑性区煤体和巷旁支护体传递给底板的作用力,提高采空区冒落矸石对底板的作用力,防止巷道底板岩层拉伸破坏,巷旁支护体宽度、刚度与底板岩层强度相匹配等底臌防控措施,并应用于工程实践。
Dynamic loads which caused by overlying strata caving pass to the floor of gob-side entry retaining through roadside coal,entry-in support and roadside support,consequently cause serious floor heave deformation in a section behind the working face. In order to control the floor heave deformation of gob-side entry retaining which caused by overlying strata caving,on the base of analyzing the mechanics environment of gob-side entry retaining,the mechanical model of the floor was established,and the width of elastic compression zone,plastic zone,the fractured zone inside the coal rib and the forces of the coal rib to floor strata were calculated. With the application of key strata theory,the location and caving order of hard rock strata,and the location of caving limit layer were determined; also,the stripe segmentation method of roof load was adopted to calculate the force of roadside support to the floor,and the concept of equivalent load was introduced,the mechanical model of floor equivalent load distribution of gob-side entry retaining was established,the overlying strata caving was closely linked with the floor heave deformation of gob-side entry retai-ning,the influence of overlying strata caving on the stress and deformation of roadway floor was analyzed,and the floor deformation formula of gob-side entry retaining was deduced. The results show that the floor heave of gob-side entry retaining was caused mainly by the high stress pressure shear failure of floor strata below plastic zone coal and roadside support and the tensile failure of roadway floor and gob floor in strong unloading conditions. Based on this,the prevention and control measures of floor heave were put forward,such as reducing the forces of plastic zone coal and roadside support to the floor,improving the force of caved gangue to the floor,preventing the floor strata of roadway from tensile failure,matching the width and stiffness of roadside support with the strength of floor strata. The research results were applied to the engineering practice to provide some references for the prevention and control of the floor heave of gobside entry retaining.
Dynamic loads which caused by overlying strata caving pass to the floor of gob-side entry retaining through roadside coal,entry-in support and roadside support,consequently cause serious floor heave deformation in a section behind the working face. In order to control the floor heave deformation of gob-side entry retaining which caused by overlying strata caving,on the base of analyzing the mechanics environment of gob-side entry retaining,the mechanical model of the floor was established,and the width of elastic compression zone,plastic zone,the fractured zone inside the coal rib and the forces of the coal rib to floor strata were calculated. With the application of key strata theory,the location and caving order of hard rock strata,and the location of caving limit layer were determined; also,the stripe segmentation method of roof load was adopted to calculate the force of roadside support to the floor,and the concept of equivalent load was introduced,the mechanical model of floor equivalent load distribution of gob-side entry retaining was established,the overlying strata caving was closely linked with the floor heave deformation of gob-side entry retai-ning,the influence of overlying strata caving on the stress and deformation of roadway floor was analyzed,and the floor deformation formula of gob-side entry retaining was deduced. The results show that the floor heave of gob-side entry retaining was caused mainly by the high stress pressure shear failure of floor strata below plastic zone coal and roadside support and the tensile failure of roadway floor and gob floor in strong unloading conditions. Based on this,the prevention and control measures of floor heave were put forward,such as reducing the forces of plastic zone coal and roadside support to the floor,improving the force of caved gangue to the floor,preventing the floor strata of roadway from tensile failure,matching the width and stiffness of roadside support with the strength of floor strata. The research results were applied to the engineering practice to provide some references for the prevention and control of the floor heave of gobside entry retaining.
引文
[1]华心祝,卢小雨,李迎富.深井大断面沿空留巷底鼓防控技术[J].煤炭科学技术,2013,41(9):100-104.Hua Xinzhu,Lu Xiaoyu,Li Yingfu.Prevention and control technology of floor heave in gob-side entry retaining with large section of deep mine[J].Coal Science and Technology,2013,41(9):100-104.
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[3]张东升,茅献彪,马文顶.综放沿空留巷围岩变形特征的试验研究[J].岩石力学与工程学报,2002,21(3):331-334.Zhang Dongsheng,Mao Xianbiao,Ma Wending.Testing study on deformation features of surrounding rocks of gob-side entry retaining in fully-mechanized coal face with top-coal caving[J].Chinese Journal of Rock Mechanics and Engineering,2002,21(3):331-334.
[4]张登龙,华心祝.深部矿井Y型通风沿空留巷围岩控制技术[J].煤炭科学技术,2010,38(12):29-32.Zhang Denglong,Hua Xinzhu.Surrounding rock control technology of gateway driven a long goaf with Y type ventilation in deep mine[J].Coal Science and Technology,2010,38(12):29-32.
[5]张农,张志义,吴海,等.深井沿空留巷扩刷修复技术及应用[J].岩石力学与工程学报,2014,33(3):468-474.Zhang Nong,Zhang Zhiyi,Wu Hai,et al.Technology and application of reparation in deep gob-side entry retaining[J].Chinese Journal of Rock Mechanics and Engineering,2014,33(3):468-474.
[6]康红普,牛多龙,张镇,等.深部沿空留巷围岩变形特征与支护技术[J].岩石力学与工程学报,2010,29(10):1977-1987.Kang Hongpu,Niu Duolong,Zhang Zhen,et al.Deformation characteristics of surrounding rock and supporting technology of gob-side entry retaining in deep coal mine[J].Chinese Journal of Rock Mechanics and Engineering,2010,29(10):1977-1987.
[7]宋振骐,宋扬,刘义学,等.内外应力场理论及其在矿压控制中的应用[A].水电与矿业工程中的岩石力学问题—中国北方岩石力学与工程应用学术会议文集[C].1991.
[8]郑桂荣,杨万斌.煤巷煤体破裂区厚度的一种计算方法[J].煤炭学报,2003,28(1):38-40.Zheng Guirong,Yang Wanbin.A calculation method of the failure zone width of side coal-wall of roadway in seams[J].Journal of China Coal Society,2003,28(1):38-40.
[9]侯朝炯,马念杰.煤层巷道两帮煤体应力和极限平衡区的探讨[J].煤炭学报,1989(4):21-29.Hou Chaojiong,Ma Nianjie.Stress in in-seam roadway sides and limlt equillbrlum zone[J].Journal of China Coal Society,1989(4):21-29.
[10]钱鸣高,缪协兴,许家林.岩层控制的关键层理论[M].徐州:中国矿业大学出版社,2003.
[11]许家林,钱鸣高.覆岩关键层位置的判别方法[J].中国矿业大学学报,2000,20(5):463-467.Xu Jialin,Qian Minggao.Method to distinguish key strata in overburden[J].Journal of China University of Mining&Technology,2000,20(5):463-467.
[12]华心祝,马俊枫,许庭教.锚杆支护巷道巷旁锚索加强支护沿空留巷围岩控制机理研究及应用[J].岩石力学与工程学报,2005,24(12):2107-2112.Hua Xinzhu,Ma Junfeng,Xu Tingjiao.Study on controlling mechanism of surrounding rocks of gob-side entry with combination of roadside reinforced cable supporting and roadway bolt supporting and its application[J].Chinese Journal of Rock Mechanics and Engineering,2005,24(12):2107-2112.
[13]柏建彪.沿空掘巷围岩控制[M].徐州:中国矿业大学出版社,2006.
[14]马念杰,侯朝炯.采准巷道矿压理论及应用[M].北京:煤炭工业出版社,1995.
[15]徐芝纶.弹性力学简明教程[M].北京:高等教育出版社,2002.
[16]周道祥,张伟林,王光钦.工程弹性力学基础[M].安徽:合肥工业大学出版社,2006.
[17]王卫军,侯朝炯,柏建彪,等.综放沿空巷道底板受力变形分析及底鼓力学原理[J].岩土力学,2001,22(3):319-322.Wang Weijun,Hou Chaojiong,Bai Jianbiao,et al.Mechanical deformation analysis and principle of floor heave of roadway driving gob in fully mechanized sub-level caving face[J].Rock and Soil Mechanics,2001,22(3):319-322.
[18]钱鸣高,石平五,许家林.矿山压力与岩层控制[M].徐州:中国矿业大学出版社,2010.
[2]孙恒虎,赵炳利.沿空留巷的理论与实践[M].北京:煤炭工业出版社,1993.
[3]张东升,茅献彪,马文顶.综放沿空留巷围岩变形特征的试验研究[J].岩石力学与工程学报,2002,21(3):331-334.Zhang Dongsheng,Mao Xianbiao,Ma Wending.Testing study on deformation features of surrounding rocks of gob-side entry retaining in fully-mechanized coal face with top-coal caving[J].Chinese Journal of Rock Mechanics and Engineering,2002,21(3):331-334.
[4]张登龙,华心祝.深部矿井Y型通风沿空留巷围岩控制技术[J].煤炭科学技术,2010,38(12):29-32.Zhang Denglong,Hua Xinzhu.Surrounding rock control technology of gateway driven a long goaf with Y type ventilation in deep mine[J].Coal Science and Technology,2010,38(12):29-32.
[5]张农,张志义,吴海,等.深井沿空留巷扩刷修复技术及应用[J].岩石力学与工程学报,2014,33(3):468-474.Zhang Nong,Zhang Zhiyi,Wu Hai,et al.Technology and application of reparation in deep gob-side entry retaining[J].Chinese Journal of Rock Mechanics and Engineering,2014,33(3):468-474.
[6]康红普,牛多龙,张镇,等.深部沿空留巷围岩变形特征与支护技术[J].岩石力学与工程学报,2010,29(10):1977-1987.Kang Hongpu,Niu Duolong,Zhang Zhen,et al.Deformation characteristics of surrounding rock and supporting technology of gob-side entry retaining in deep coal mine[J].Chinese Journal of Rock Mechanics and Engineering,2010,29(10):1977-1987.
[7]宋振骐,宋扬,刘义学,等.内外应力场理论及其在矿压控制中的应用[A].水电与矿业工程中的岩石力学问题—中国北方岩石力学与工程应用学术会议文集[C].1991.
[8]郑桂荣,杨万斌.煤巷煤体破裂区厚度的一种计算方法[J].煤炭学报,2003,28(1):38-40.Zheng Guirong,Yang Wanbin.A calculation method of the failure zone width of side coal-wall of roadway in seams[J].Journal of China Coal Society,2003,28(1):38-40.
[9]侯朝炯,马念杰.煤层巷道两帮煤体应力和极限平衡区的探讨[J].煤炭学报,1989(4):21-29.Hou Chaojiong,Ma Nianjie.Stress in in-seam roadway sides and limlt equillbrlum zone[J].Journal of China Coal Society,1989(4):21-29.
[10]钱鸣高,缪协兴,许家林.岩层控制的关键层理论[M].徐州:中国矿业大学出版社,2003.
[11]许家林,钱鸣高.覆岩关键层位置的判别方法[J].中国矿业大学学报,2000,20(5):463-467.Xu Jialin,Qian Minggao.Method to distinguish key strata in overburden[J].Journal of China University of Mining&Technology,2000,20(5):463-467.
[12]华心祝,马俊枫,许庭教.锚杆支护巷道巷旁锚索加强支护沿空留巷围岩控制机理研究及应用[J].岩石力学与工程学报,2005,24(12):2107-2112.Hua Xinzhu,Ma Junfeng,Xu Tingjiao.Study on controlling mechanism of surrounding rocks of gob-side entry with combination of roadside reinforced cable supporting and roadway bolt supporting and its application[J].Chinese Journal of Rock Mechanics and Engineering,2005,24(12):2107-2112.
[13]柏建彪.沿空掘巷围岩控制[M].徐州:中国矿业大学出版社,2006.
[14]马念杰,侯朝炯.采准巷道矿压理论及应用[M].北京:煤炭工业出版社,1995.
[15]徐芝纶.弹性力学简明教程[M].北京:高等教育出版社,2002.
[16]周道祥,张伟林,王光钦.工程弹性力学基础[M].安徽:合肥工业大学出版社,2006.
[17]王卫军,侯朝炯,柏建彪,等.综放沿空巷道底板受力变形分析及底鼓力学原理[J].岩土力学,2001,22(3):319-322.Wang Weijun,Hou Chaojiong,Bai Jianbiao,et al.Mechanical deformation analysis and principle of floor heave of roadway driving gob in fully mechanized sub-level caving face[J].Rock and Soil Mechanics,2001,22(3):319-322.
[18]钱鸣高,石平五,许家林.矿山压力与岩层控制[M].徐州:中国矿业大学出版社,2010.