Research on borehole gas extraction based on the influence of mining height on the evolution of overburden fracture in working face
-
摘要:
采动覆岩裂隙演化规律对层间瓦斯运移起主导作用，研究覆岩裂隙发育分布规律对于提高瓦斯抽采效率至关重要。以甘肃省魏家地矿西2107综采工作面为工程背景，采用UDEC模拟软件建立不同采高的数值模型，利用分形几何理论分析了工作面覆岩近场裂隙演化与不同开采高度的关系，确定了钻孔瓦斯抽采最优工作面高度，并通过理论经验公式、覆岩裂隙窥视情况与现场瓦斯抽采结果对其验证。结果表明：采动裂隙总数随着采高增大而增大，但不同阶段增大的幅度皆不相同，覆岩裂隙不断向覆岩四周呈“伞状”发育；不同开采高度的工作面覆岩近场裂隙均经历产生、扩张贯通、压实稳定的3个阶段，且采高越大，压实区范围越小，适当增加采高，有助于提高覆岩瓦斯抽采效果；当采高选择4 m时，顶板裂隙在位于10 m与40 m位置处的裂隙发育密度与范围均明显大于其他区域，该区域与布置高、低巷双位一体的协同抽采巷最佳位置相一致。
Abstract:The evolution of fractures in mining overburden plays a pivotal role in interlayer gas migration. Therefore, a comprehensive study of crack development and distribution improve the efficiency of gas extraction. This study the west 2107 fully mechanized mining face in Weijia Mine of Gansu Province as the engineering background, Specifically, this study established numerical models of different mining heights by using the UDEC simulation software, and analyzed the relationship between the evolution of near-field fractures in the overburden of the working face and different mining based on fractal geometry theory. The optimal working face height for gas extraction was determined and validated through theoretical empirical formulas, field observations of overburden fractures, and gas extraction results. The results show that the total number of mining fractures increases with the increase of mining height, but the amplitude of increase is different at different stages, and the overburden fractures continue to develop in an "umbrella" shape around the overburden. The near-field fractures of the overburden rock at different mining heights have undergone three stages: generation, expansion and penetration, and compaction stability. Increasing mining height, smaller compaction zones. When the mining height is 4 m, the development density and range of roof fractures at 10 m and 40 m are significantly higher than those in other areas, which is consistent with the optimal position of the collaborative extraction roadway with high and low roadways.
-
Key words:
- gas extraction /
- height mining /
- fracture development /
- numerical simulation /
- fractal effects
-
图 3 不同采高工作面推进不同距离覆岩裂隙演化
Figure 3. Overburden rock fracture evolution with different advancing different distances at different mining height in the working face
图 4 工作面推进不同距离覆岩裂隙二值图、分形维数图
Figure 4. The binary diagram of fractures in mining overburden rock at working face and numerical diagram of fractal dimension
图 5 不同采高覆岩裂隙发育特征与分形维数关系
Figure 5. Relationship between fracture development characteristics at different heights at different heights and fractal dimension of overlying strata
图 6 不同采高工作面覆岩裂隙密度演化曲线
Figure 6. The overburden rock fracture density evolution curve of working face at different mining heights
图 7 工作面高、低位瓦斯抽采巷布置示意图
Figure 7. High and low gas drainage roadway layout of working face
图 9 工作面高、低抽巷瓦斯抽采量变化曲线
Figure 9. Variation characteristics of gas drainage quantity in high and low drainage roadways of working face
图 10 回风巷、上隅角瓦斯浓度现场监测变化曲线
Figure 10. Gas concentration in return airway and upper corner
表 1 煤岩物理力学参数表
Table 1. Physical and mechanical parameters of coal and rock strata
岩性 岩石密度/(kg·m-3) 体积模量/GPa 剪切模量/GPa 抗拉强度/MPa 黏聚力/MPa 内摩擦角/(°) 砂质泥岩 2 480 1.75 4.28 2.21 4.93 33 粉砂岩 2 355 3.67 8.15 3.60 6.06 35 细粉砂岩 2 130 2.09 7.28 3.43 6.42 38 粗细砾砂岩 2 235 5.72 10.34 4.86 5.87 39 泥质粉砂岩 2 385 7.59 7.59 7.16 4.89 41 炭质泥岩 2 440 5.43 4.81 4.21 4.93 33 煤层 1 425 1.82 0.45 0.42 3.67 22 
下载: 导出CSV
表 2 不同采高工作面覆岩裂隙发育特征与分形维数关系
Table 2. Relationship between fracture development characteristics and fractal dimension of overlying strata in working face with different mining heights
开采高度/m 开采距离/m 分形维数 相关系数 覆岩裂隙发育特征 2 40 1.137 0.898 裂隙产生后发育迅速 80 1.185 0.989 裂隙逐渐扩张后渐渐压实 120 1.189 0.996 内部裂隙渐渐压实 160 1.215 0.997 覆岩裂隙逐渐压实且趋于稳定 4 40 1.152 0.996 裂隙产生后逐渐贯通 80 1.183 0.995 裂隙迅速扩张后渐渐压实 120 1.219 0.998 内部裂隙压实 160 1.269 0.993 覆岩裂隙压实且趋于稳定 6 40 1.193 0.988 裂隙产生后迅速贯通 80 1.236 0.980 裂隙迅速扩张后压实 120 1.287 0.982 内部裂隙压实 160 1.342 0.982 覆岩整体垮落且趋于稳定 8 40 1.263 0.977 裂隙产生后迅速发育贯通 80 1.328 0.978 裂隙迅速扩张后压实 120 1.367 0.972 内部裂隙压实 160 1.392 0.968 覆岩整体垮落且趋于稳定
下载: 导出CSV
-
[1] 谢和平, 吴立新, 郑德志. 2025年中国能源消费及煤炭需求预测[J]. 煤炭学报, 2019, 44(7): 1949-1960. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201907001.htmXIE Heping, WU Lixin, ZHENG Dezhi. Prediction on the energy consumption and coal demand of China in 2025[J]. Journal of China Coal Society, 2019, 44(7): 1949-1960. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201907001.htm [2] 武强, 涂坤, 曾一凡, 等. 打造我国主体能源(煤炭)升级版面临的主要问题与对策探讨[J]. 煤炭学报, 2019, 44(6): 1625-1636. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201906001.htmWU Qiang, TU Kun, ZENG Yifan, et al. Discussion on the main problems and countermeasures for building an upgrade version of main energy(coal) industry in China[J]. Journal of China Coal Society, 2019, 44(6): 1625-1636. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201906001.htm [3] 韩可琦, 王玉浚. 中国能源消费的发展趋势与前景展望[J]. 中国矿业大学学报, 2004, 33(1): 23-31. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD200401000.htmHAN Keqi, WANG Yujun. Developing trend and expectation of energy consume in China[J]. Journal of China University of Mining & Technology, 2004, 33(1): 23-31. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD200401000.htm [4] 潘一山. 煤与瓦斯突出、冲击地压复合动力灾害一体化研究[J]. 煤炭学报, 2016, 41(1): 105-112. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201601016.htmPAN Yishan. Integrated study on compound dynamic disaster of coal-gas outburst and rockburst[J]. Journal of China Coal Society, 2016, 41(1): 105-112. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201601016.htm [5] 王恩元, 张国锐, 张超林, 等. 我国煤与瓦斯突出防治理论技术研究进展与展望[J]. 煤炭学报, 2022, 47(1): 297-322. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB202201021.htmWANG Enyuan, ZHANG Guorui, ZHANG Chaolin, et al. Research progress and prospect on theory and technology for coal and gas outburst control and protection in China[J]. Journal of China Coal Society, 2022, 47(1): 297-322. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB202201021.htm [6] 刘国磊, 王泽东, 曲效成, 等. 低透气性煤层工作面煤与瓦斯突出灾害中心体致灾机理[J]. 煤炭科学技术, 2022, 50(10): 76-85. https://www.cnki.com.cn/Article/CJFDTOTAL-MTKJ202210010.htmLIU Guolei, WANG Zedong, QU Xiaocheng, et al. Mechanism of coal and gas outburst disaster center in low permeability coal seam mining face[J]. Coal Science and Technology, 2022, 50(10): 76-85. https://www.cnki.com.cn/Article/CJFDTOTAL-MTKJ202210010.htm [7] 赵洪宝, 王涛, 张欢, 等. 透气夹矸对煤样渗透特性影响的试验研究[J]. 中国矿业大学学报, 2019, 48(1): 29-35. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD201901004.htmZHAO Hongbao, WANG Tao, ZHANG Huan, et al. Experimental study of the effect of penetration gangue on coal permeability[J]. Journal of China University of Mining & Technology, 2019, 48(1): 29-35. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD201901004.htm [8] 闫浩, 张吉雄, 鞠杨, 等. 上保护层开采下充实率控制裂隙发育规律及瓦斯抽采研究[J]. 采矿与安全工程学报, 2018, 35(6): 1262-1268. https://www.cnki.com.cn/Article/CJFDTOTAL-KSYL201806025.htmYAN Hao, ZHANG Jixiong, JU Yang, et al. Fracture development rules controlled by backfill body's compression ratio and gas drainage technology under upper protective layer mining[J]. Journal of Mining & Safety Engineering, 2018, 35(6): 1262-1268. https://www.cnki.com.cn/Article/CJFDTOTAL-KSYL201806025.htm [9] 袁亮. 卸压开采抽采瓦斯理论及煤与瓦斯共采技术体系[J]. 煤炭学报, 2009, 34(1): 1-8. doi: 10.3321/j.issn:0253-9993.2009.01.001YUAN Liang. Theory of pressure-relieved gas extraction and technique system of integrated coal production and gas extraction[J]. Journal of China Coal Society, 2009, 34(1): 1-8. doi: 10.3321/j.issn:0253-9993.2009.01.001 [10] 胡国忠, 李康, 许家林, 等. 覆岩采动裂隙空间形态反演方法及在瓦斯抽采中的应用[J]. 煤炭学报, 2023, 48(2): 750-762. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB202302015.htmHU Guozhong, LI Kang, XU Jialin, et al. Spatial morphology inversion method of mining-induced fractures of overburden and its application in gas drainage[J]. Journal of China Coal Society, 2023, 48(2): 750-762. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB202302015.htm [11] 郭明杰, 郭文兵, 袁瑞甫, 等. 基于采动裂隙区域分布特征的定向钻孔空间位置研究[J]. 采矿与安全工程学报, 2022, 39(4): 817-826. https://www.cnki.com.cn/Article/CJFDTOTAL-KSYL202204019.htmGUO Mingjie, GUO Wenbing, YUAN Ruifu, et al. Spatial location determination of directional boreholes based on regional distribution characteristics of mining-induced overburden fractures[J]. Journal of Mining & Safety Engineering, 2022, 39(4): 817-826. https://www.cnki.com.cn/Article/CJFDTOTAL-KSYL202204019.htm [12] 刘天泉. 矿山岩体采动影响与控制工程学及其应用[J]. 煤炭学报, 1995, 20(1): 21-23. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB501.000.htmLIU Tianquan. Mining influence and control engineering of mine rock mass and its application[J]. Journal of China Coal Society, 1995, 20(1): 21-23. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB501.000.htm [13] 钱鸣高, 许家林. 煤炭开采与岩层运动[J]. 煤炭学报, 2019, 44(4): 973-984. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201904001.htmQIAN Minggao, XU Jialin. Behaviors of strata movement in coal mining[J]. Journal of China Coal Society, 2019, 44(4): 973-984. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201904001.htm [14] 卢平, 袁亮, 程桦, 等. 低透气性煤层群高瓦斯采煤工作面强化抽采卸压瓦斯机理及试验[J]. 煤炭学报, 2010, 35(4): 580-585. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201004014.htmLU Ping, YUAN Liang, CHENG Hua, et al. Theory and experimental studies of enhanced gas drainage in the high-gas face of low permeability coal multi-seams[J]. Journal of China Coal Society, 2010, 35(4): 580-585. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201004014.htm [15] 李树刚, 刘李东, 赵鹏翔, 等. 综采工作面覆岩压实区裂隙动态演化规律影响因素分析[J]. 煤炭科学技术, 2022, 50(1): 95-104. https://www.cnki.com.cn/Article/CJFDTOTAL-MTKJ202201008.htmLI Shugang, LIU Lidong, ZHAO Pengxiang, et al. Analysis and application of fracture evolution law of overburden compacted area on fully-mechanized mining face under multiple factors[J]. Coal Science and Technology, 2022, 50(1): 95-104. https://www.cnki.com.cn/Article/CJFDTOTAL-MTKJ202201008.htm [16] 俞启香, 程远平, 蒋承林, 等. 高瓦斯特厚煤层煤与卸压瓦斯共采原理及实践[J]. 中国矿业大学学报, 2004, 33(2): 127-131. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD200402001.htmYU Qixiang, CHENG Yuanping, JIANG Chenglin, et al. Principles and applications of exploitation of coal and pressure relief gas in thick and high-gas seams[J]. Journal of China University of Mining & Technology, 2004, 33(2): 127-131. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD200402001.htm [17] 齐庆新, 季文博, 元继宏, 等. 底板贯穿型裂隙现场实测及其对瓦斯抽采的影响[J]. 煤炭学报, 2014, 39(8): 1552-1558. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201408025.htmQI Qingxin, JI Wenbo, YUAN Jihong, et al. In-situ observation on the floor-connected crack field and its effects on methane extraction[J]. Journal of China Coal Society, 2014, 39(8): 1552-1558. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201408025.htm [18] 谢和平, 周宏伟, 薛东杰, 等. 我国煤与瓦斯共采: 理论、技术与工程[J]. 煤炭学报, 2014, 39(8): 1391-1397. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201408003.htmXIE Heping, ZHOU Hongwei, XUE Dongjie, et al. Theory, technology and engineering of simultaneous exploitation of coal and gas in China[J]. Journal of China Coal Society, 2014, 39(8): 1391-1397. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201408003.htm [19] 徐超, 王凯, 郭琳, 等. 采动覆岩裂隙与渗流分形演化规律及工程应用[J]. 岩石力学与工程学报, 2022, 41(12): 2389-2403. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX202212002.htmXU Chao, WANG Kai, GUO Lin, et al. Fractal evolution law of overlying rock fracture and seepage caused by mining and its engineering application[J]. Chinese Journal of Rock Mechanics and Engineering, 2022, 41(12): 2389-2403. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX202212002.htm [20] 王登科, 魏强, 魏建平, 等. 煤的裂隙结构分形特征与分形渗流模型研究[J]. 中国矿业大学学报, 2020, 49(1): 103-109, 122. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD202001012.htmWANG Dengke, WEI Qiang, WEI Jianping, et al. Fractal characteristics of fracture structure and fractal seepage model of coal[J]. Journal of China University of Mining & Technology, 2020, 49(1): 103-109, 122. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD202001012.htm [21] 赵阳升, 马宇, 段康廉. 岩层裂缝分形分布相关规律研究[J]. 岩石力学与工程学报, 2002, 21(2): 219-222. doi: 10.3321/j.issn:1000-6915.2002.02.013ZHAO Yangsheng, MA Yu, DUAN Kanglian. Study on the co-relation law of fractal distribution of crack in rock stratum[J]. Chinese Journal of Rock Mechanics and Engineering, 2002, 21(2): 219-222. doi: 10.3321/j.issn:1000-6915.2002.02.013 [22] 黄志安, 童海方, 张英华, 等. 采空区上覆岩层"三带" 的界定准则和仿真确定[J]. 北京科技大学学报, 2006, 28(7): 609-612. doi: 10.3321/j.issn:1001-053X.2006.07.001HUANG Zhian, TONG Haifang, ZHANG Yinghua, et al. Dividing guideline and emulating determination of "three zones" of the depressing zones overlying a goaf[J]. Journal of University of Science and Technology Beijing, 2006, 28(7): 609-612. doi: 10.3321/j.issn:1001-053X.2006.07.001 [23] 王春来, 侯晓琳, 李海涛, 等. 单轴压缩砂岩细观裂纹动态演化特征试验研究[J]. 岩土工程学报, 2019, 41(11): 2120-2125. doi: 10.11779/CJGE201911018WANG Chunlai, HOU Xiaolin, LI Haitao, et al. Experimental investigation on dynamic evolution characteristics of micro-cracks for sandstone samples under uniaxial compression[J]. Chinese Journal of Geotechnical Engineering, 2019, 41(11): 2120-2125. doi: 10.11779/CJGE201911018 [24] 赵洪宝, 刘绍强, 康钦容, 等. 基于数字分形原理的矿区粉尘时空分布与防治技术[J]. 矿业科学学报, 2022, 7(6): 710-719. doi: 10.19606/j.cnki.jmst.2022.06.008ZHAO Hongbao, LIU Shaoqiang, KANG Qinrong, et al. Temporal and spatial distribution and prevention of dust in mining area based on digital fractal principle[J]. Journal of Mining Science and Technology, 2022, 7(6): 710-719. doi: 10.19606/j.cnki.jmst.2022.06.008 [25] 赵明凯, 孔德森. 考虑裂隙面粗糙度和开度分形维数的岩石裂隙渗流特性研究[J]. 岩石力学与工程学报, 2022, 41(10): 1993-2002. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX202210005.htmZHAO Mingkai, KONG Desen. Study on seepage characteristics of rock fractures considering fracture surface roughness and opening fractal dimension[J]. Chinese Journal of Rock Mechanics and Engineering, 2022, 41(10): 1993-2002. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX202210005.htm [26] 张玉军, 申晨辉, 张志巍, 等. 我国厚及特厚煤层高强度开采导水裂缝带发育高度区域分布规律[J]. 煤炭科学技术, 2022, 50(5): 38-48. https://www.cnki.com.cn/Article/CJFDTOTAL-MTKJ202205005.htmZHANG Yujun, SHEN Chenhui, ZHANG Zhiwei, et al. Regional distribution law of water-conducting fractured zone height in high-strength mining of thick and extra-thick coal seams in China[J]. Coal Science and Technology, 2022, 50(5): 38-48. https://www.cnki.com.cn/Article/CJFDTOTAL-MTKJ202205005.htm [27] 杨达明, 郭文兵, 赵高博, 等. 厚松散层软弱覆岩下综放开采导水裂隙带发育高度[J]. 煤炭学报, 2019, 44(11): 3308-3316. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201911003.htmYANG Daming, GUO Wenbing, ZHAO Gaobo, et al. Height of water-conducting zone in longwall top-coal caving mining under thick alluvium and soft overburden[J]. Journal of China Coal Society, 2019, 44(11): 3308-3316. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB201911003.htm -
点击查看大图
计量
- 文章访问数: 26
- HTML全文浏览量: 7
- PDF下载量: 12
- 被引次数: 0