Calculation of direct roof subsidence of retracement channel and analysis of its influencing factors
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摘要: 回撤通道的直接顶下沉量对设备回撤具有重要影响,本文基于基本顶断裂位置,建立了工作面贯通后回撤通道直接顶挠度力学模型,将支承应力表达式简化为与其拟合的x的n次抛物线函数,断裂位置不同,n的取值不同,推导出了回撤通道顶板中心线处直接顶下沉量表达式。312工作面基本顶断裂位置d约12 m,此时n取4,求得直接顶下沉量约为105 mm。在理论计算的基础上,对直接顶下沉量影响因素进行了分析,结果表明:直接顶下沉量随着基本顶断裂位置、煤层埋深、应力集中系数及回撤通道跨度的增大而增加,随着直接顶厚度及弹性模量的增大而减小,其余因素影响较弱。在保证设备回撤空间的条件下,尽可能减小回撤通道跨度,控制直接顶下沉量。Abstract: The direct roof subsidence of retracement channel is of utmost importanie to the withdrawal of equipment in the final mining stage.Based on the basic roof fracture position, a mechanical model of the direct roof deflection of the withdrawal channel after penetration was established.The expression of the supporting stress was simplified to the n-th parabolic function of x fitted to it.The value of n varies with the fracture position, the expression of the direct roof subsidence at the center line of the roof of the retreat channel was derived.The basic roof fracture position d of 312 working face was about 12 m, at this time n was taken as 4, and the direct roof subsidence was about 105 mm.On the basis of theoretical calculations, the factors affecting the direct roof subsidence were analyzed.The results showed: The direct roof subsidence increases with the increase of the basic roof fracture location, coal seam depth, stress concentration coefficient and the span of the retreat channel, and decreases with the increase of the direct roof thickness and elastic modulus.The influence of other factors is not significant.Under the condition of ensuring the equipment withdrawal space, the span of the withdrawal channel should be reduced as much as possible to control the direct subsidence of the withdrawal channel.
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表 1 312工作面地质及工程参数
Table 1. Geological and engineering parameters of 312 working face
参数符号 单位 数值 工作面埋深H m 500 上覆岩层容重γ MPa/m 0.025 应力峰值系数k - 2.6~3.0 直接顶厚度h0 m 3.78 直接顶弹性模量E GPa 26 平均采高M m 3.2 煤层泊松比μ - 0.25 出煤巷宽度D1 m 4.2 支架控顶距D2 m 4.6 出煤巷支护阻力f1 MPa 0.25 支架工作阻力f2 MPa 0.64 -
[1] 马晋民, 邵民超, 石晋松, 等. 综采工作面支架回撤工艺研究[J]. 煤炭科学技术, 2016, 44(S1): 21-23. https://www.cnki.com.cn/Article/CJFDTOTAL-MTKJ2016S1006.htmMa Jinmin, Shao Minchao, Shi Jinsong, et al. Research on supports retracement process of fully-mechanized coal mining face[J]. Coal Science and Technology, 2016, 44(S1): 21-23. https://www.cnki.com.cn/Article/CJFDTOTAL-MTKJ2016S1006.htm [2] 吕华文. 预掘回撤通道稳定性机理分析及应用[J]. 煤炭学报, 2014, 39(S1): 50-56. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB2014S1009.htmLü Huawen. The mechanism of stability of pre-driven rooms and the practical techniques[J]. Journal of China Coal Society, 2014, 39(S1): 50-56. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB2014S1009.htm [3] 杨军, 高玉兵, 刘世奇, 等. 动压扰动采准巷道围岩失稳机理及控制研究[J]. 矿业科学学报, 2018, 3(5): 451-460. http://kykxxb.cumtb.edu.cn/article/id/171Yang Jun, Gao Yubing, Liu Shiqi, et al. Study on failure mechanism and control techniques of the preparation roadway induced by dynamic mining disturbance[J]. Journal of Mining Science and Technology, 2018, 3(5): 451-460. http://kykxxb.cumtb.edu.cn/article/id/171 [4] 张红军, 李海燕, 李术才, 等. 深部软岩巷道围岩变形机制及支护技术研究[J]. 采矿与安全工程学报, 2015, 32(6): 955-962. https://www.cnki.com.cn/Article/CJFDTOTAL-KSYL201506015.htmZhang Hongjun, Li Haiyan, Li Shucai, et al. Deformation mechanism of surrounding rock and support technology in deep soft rock roadway[J]. Journal of Mining & Safety Engineering, 2015, 32(6): 955-962. https://www.cnki.com.cn/Article/CJFDTOTAL-KSYL201506015.htm [5] 赵洪宝, 刘一洪, 程辉, 等. 回坡底煤矿回采巷道非对称底鼓机理及防治措施[J]. 矿业科学学报, 2020, 5(6): 638-647. doi: 10.19606/j.cnki.jmst.2020.06.006Zhao Hongbao, Liu Yihong, Cheng Hui, et al. Mechanism and prevention measures of asymmetric floor heave in mining roadway of Huipodi Coal Mine[J]. Journal of Mining Science and Technology, 2020, 5(6): 638-647. doi: 10.19606/j.cnki.jmst.2020.06.006 [6] 钱鸣高, 缪协兴, 何富连, 等. 采场支架与围岩耦合作用机理研究[J]. 煤炭学报, 1996, 21(1): 40-44. doi: 10.3321/j.issn:0253-9993.1996.01.008Qian Minggao, Miao Xiexing, He Fulian, et al. Mechanism of coupling effect between supports in the workings and the rocks[J]. Journal of China Coal Society, 1996, 21(1): 40-44. doi: 10.3321/j.issn:0253-9993.1996.01.008 [7] 高峰, 钱鸣高, 缪协兴. 老顶给定变形下直接顶受力变形分析[J]. 岩石力学与工程学报, 2000, 19(2): 145-148. doi: 10.3321/j.issn:1000-6915.2000.02.004Gao Feng, Qian Minggao, Miao Xiexing. Mechanical analysis of the immediate roof subjected to given deformation of the main roof[J]. Chinese Journal of Rock Mechanics and Engineering, 2000, 19(2): 145-148. doi: 10.3321/j.issn:1000-6915.2000.02.004 [8] 高峰, 钱鸣高, 缪协兴. 采场支架工作阻力与顶板下沉量类双曲线关系的探讨[J]. 岩石力学与工程学报, 1999, 18(6): 658-662. doi: 10.3321/j.issn:1000-6915.1999.06.009Gao Feng, Qian Minggao, Miao Xiexing. Discussion on the hyperbolic relation between support resistance and immediate roofsubsidence[J]. Chinese Journal of Rock Mechanics and Engineering, 1999, 18(6): 658-662. doi: 10.3321/j.issn:1000-6915.1999.06.009 [9] 杨惠斌, 王志刚, 赵银虎, 等. 大采高综采工作面回撤通道顶板控制技术研究[J]. 矿业安全与环保, 2014, 41(5): 59-61, 68. doi: 10.3969/j.issn.1008-4495.2014.05.016Yang Huibin, Wang Zhigang, Zhao Yinhu, et al. Study on roof control technology for withdrawal passageway in fully mechanized coal face with large mining height[J]. Mining Safety & Environmental Protection, 2014, 41(5): 59-61, 68. doi: 10.3969/j.issn.1008-4495.2014.05.016 [10] 万镇. 综采工作面设备回撤通道围岩控制研究[D]. 青岛: 山东科技大学, 2009. [11] 马新根, 何满潮, 李先章, 等. 切顶卸压自动成巷覆岩变形机理及控制对策研究[J]. 中国矿业大学学报, 2019, 48(3): 474-483. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD201903002.htmMa Xingen, He Manchao, Li Xianzhang, et al. Deformation mechanism and control measures of overlying strata with gob-side entry retaining formed by roof cutting and pressure releasing[J]. Journal of China University of Mining & Technology, 2019, 48(3): 474-483. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD201903002.htm [12] 王博楠. 回撤通道围岩变形破坏机理及其控制技术研究[D]. 西安: 西安科技大学, 2017. [13] 李全生, 徐祝贺, 张勇, 等. 基于Hoek-Brown准则的薄基岩厚松散层覆岩变形破坏特征研究[J]. 矿业科学学报, 2019, 4(5): 417-424. http://kykxxb.cumtb.edu.cn/article/id/241Li Quansheng, Xu Zhuhe, Zhang Yong, et al. Study on deformation and failure characteristics of overlying strata with thick loose layers and thin bedrock based on Hoek-Brown criterion[J]. Journal of Mining Science and Technology, 2019, 4(5): 417-424. http://kykxxb.cumtb.edu.cn/article/id/241 [14] 李永亮, 王宇轩, 林海, 等. 两侧采空巷道挤压变形机理与控制对策[J]. 矿业科学学报, 2020, 5(5): 511-518. doi: 10.19606/j.cnki.jmst.2020.05.005Li Yongliang, Wang Yuxuan, Lin Hai, et al. Squeezing deformation mechanism and control technology of roadway between two goafs[J]. Journal of Mining Science and Technology, 2020, 5(5): 511-518. doi: 10.19606/j.cnki.jmst.2020.05.005 [15] 郝登云, 崔千里, 何杰, 等. 锚杆锚索支护巷道层状顶板变形特征及离层监测研究[J]. 煤炭学报, 2017, 42(S1): 43-50. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB2017S1007.htmHao Dengyun, Cui Qianli, He Jie, et al. Deformation characteristics and separation monitoring of layered roof roadway supported with bolts and cables[J]. Journal of China Coal Society, 2017, 42(S1): 43-50. https://www.cnki.com.cn/Article/CJFDTOTAL-MTXB2017S1007.htm [16] 单仁亮, 黄博, 宋永威, 等. 新峪矿采空区下近距离巷道矿压特征研究[J]. 矿业科学学报, 2016, 1(1): 29-37. http://kykxxb.cumtb.edu.cn/article/id/7Shan Renliang, Huang Bo, Song Yongwei, et al. Ground pressure features of roadway under close range goaf in the Xinyu Mine[J]. Journal of Mining Science and Technology, 2016, 1(1): 29-37. http://kykxxb.cumtb.edu.cn/article/id/7 [17] 程占博, 孔德中, 杨敬虎. 综放工作面厚硬顶板破断特征与支架工作阻力确定[J]. 矿业科学学报, 2016, 1(2): 172-180. http://kykxxb.cumtb.edu.cn/article/id/24Cheng Zhanbo, Kong Dezhong, Yang Jinghu. The breaking characteristics of thick-hard roof and determination of support capacity in fully mechanized caving face[J]. Journal of Mining Science and Technology, 2016, 1(2): 172-180. http://kykxxb.cumtb.edu.cn/article/id/24 [18] 张金虎. 破碎顶板回撤通道围岩运动规律和支护适应性研究[J]. 煤炭科学技术, 2015, 43(12): 28-31. https://www.cnki.com.cn/Article/CJFDTOTAL-MTKJ201512006.htmZhang Jinhu. Study on movement law of surrounding rock and support adaptability of the broken roof in return channel[J]. Coal Science and Technology, 2015, 43(12): 28-31. https://www.cnki.com.cn/Article/CJFDTOTAL-MTKJ201512006.htm [19] 王志强, 王树帅, 苏泽华, 等. 走向工作面贯通上山与支架快速回撤技术[J]. 中国安全生产科学技术, 2020, 16(1): 18-24. https://www.cnki.com.cn/Article/CJFDTOTAL-LDBK202001004.htmWang Zhiqiang, Wang Shushuai, Su Zehua, et al. Technologies of uphill transfixion and rapid retracing of brackets in along strike working face[J]. Journal of Safety Science and Technology, 2020, 16(1): 18-24. https://www.cnki.com.cn/Article/CJFDTOTAL-LDBK202001004.htm [20] 王晓振, 许家林, 朱卫兵, 等. 浅埋综采面高速推进对周期来压特征的影响[J]. 中国矿业大学学报, 2012, 41(3): 349-354. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD201203004.htmWang Xiaozhen, Xu Jialin, Zhu Weibing, et al. Influence of high mining velocity on periodic weighting during fully-mechanized mining in a shallow seam[J]. Journal of China University of Mining & Technology, 2012, 41(3): 349-354. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD201203004.htm [21] 谷拴成, 黄荣宾, 李金华, 等. 工作面贯通前矿压调整时剩余煤柱稳定性分析[J]. 采矿与安全工程学报, 2017, 34(1): 60-66. https://www.cnki.com.cn/Article/CJFDTOTAL-KSYL201701009.htmGu Shuancheng, Huang Rongbin, Li Jinhua, et al. Stability analysis of un-mined coal Pillars during the pressure adjustment prior to working face transfixion[J]. Journal of Mining & Safety Engineering, 2017, 34(1): 60-66. https://www.cnki.com.cn/Article/CJFDTOTAL-KSYL201701009.htm