我国目前煤炭地下长壁开采活动中，在各工作面之间留设顺槽煤柱隔离采动影响，从而保证采准顺槽巷道的稳定性，确定煤柱合理留设宽度对保证回采过程中顺槽稳定性、提高煤炭回收率及避免能源枯竭具有重要的工程价值和意义。本文以张家峁煤矿5^-2煤层15211工作面为工程背景，通过现场调研、室内试验、理论分析、现场监测及数值模拟对小煤柱稳定性及合理留设宽度进行研究，在安全生产的同时实现绿色开采。本文主要研究成果如下：

（1）通过室内实验为确定煤岩体基本物理力学参数；通过现场调研结合理论分析地质条件、采煤方法、时间因素、煤岩体力学性质对煤柱稳定性的影响；对传统煤柱载荷及强度理论进行概述，确定本文采用A.H.Wilson煤柱载荷理论及Bieniawski强度理论，对煤柱回采过程中保持稳定的弹性核区宽度计算提供理论依据。

（2）通过对回采过程中煤柱应力变化进行监测，为力学模型建立提供现实依据，对深部位移及塑性区范围进行监测，对理论计算的塑性区宽度进行验证。基于监测结果表明煤柱弹性核区宽度过大、结构较完整且承载力较高，不利于资源回收，所以需对煤柱留设宽度进行优化。

（3）对不同煤柱宽度支承压力叠加规律进行分析，将“煤柱-底板”看做整体，建立弹性地基梁力学模型，通过“摩尔-库伦”破坏准则确定煤柱两侧的塑性区宽度计算公式；基于控制变量法对影响煤柱塑性区宽度因素进行分析；采用载荷理论和强度理论确定在已知塑性区宽度情况下，煤柱保持稳定的最小弹性核区宽度。考虑到回采过程的安全性和支护成本及资源回收率，确定张家峁5^-2煤层合理留设宽度为10.5m。

（4）通过FLAC^3D数值模拟软件对不同宽度煤柱进行模拟分析，结合现场监测对理论计算的塑性区宽度进行验证；确定在回采过程中煤柱保持稳定的宽度范围，验证理论计算小煤柱留设宽度为10.5m的合理性。

In China 's current coal underground long-wall mining activities, it is of great engineering value and significance to set up crossheading coal pillars between working faces to isolate the mining influence, so as to ensure the stability of the mining roadway, and to determine the reasonable width of the coal pillar to ensure the stability of the crossheading in the mining process, improve the coal recovery rate and avoid energy depletion.This paper takes 15211 working face of 5^-2 coal seam in Zhangjiamao coal mine as the engineering background, and studies the stability and reasonable width of small coal pillar through field research, indoor test, theoretical analysis, field monitoring and numerical simulation to achieve green mining while producing safely. The main research results of this paper are as follows:

（1）Indoor physical mechanics experiments were conducted to provide basic parameters for theoretical calculations and numerical simulations. Based on field research combined with theoretical analysis of the effects of geological conditions, coal mining methods, time factors, and mechanical properties of coal and rock bodies on the stability of coal pillars. An overview of traditional coal pillar load and strength theories is given, and it is determined that A.H. Wilson coal pillar load theory and Bieniawski strength theory are used in this paper to provide theoretical basis for calculating the width of elastic core zone for maintaining stability during coal pillar retrieval.

（2）By monitoring the change of coal pillar stress in the process of mining, it provides a realistic basis for the establishment of mechanical model, monitors the range of deep displacement and plastic zone, and verifies the width of plastic zone calculated theoretically. Based on the monitoring results, the width of the elastic core area of the coal pillar is too large, the structure is complete and the bearing capacity is high, which is not conducive to resource recovery, so it is necessary to optimize the width of the coal pillar.

（3）The superposition law of abutment pressure of different coal pillar widths is analyzed. The coal pillar-floor ' is regarded as a whole, and the mechanical model of elastic foundation beam is established. The calculation formula of plastic zone width on both sides of coal pillar is determined by ' Mohr-Coulomb ' failure criterion. Based on the control variable method, the factors affecting the width of plastic zone of coal pillar are analyzed. The load theory and strength theory are used to determine the minimum elastic core width of the coal pillar under the condition of known plastic zone width. Considering the safety of the mining process, support cost and resource recovery rate, the reasonable width of Zhangjiamao 5^-2 coal seam is 10.5 m.

（4）Simulation analysis of coal pillars with different widths is carried out by FLAC^3D numerical simulation software, and the theoretically calculated width of plastic zone is verified by combining with field monitoring. Determine the width range of coal pillar to keep stable during the retrieval process, and verify the reasonableness of the theoretical calculation of small coal pillar leaving width of 10.5m.

[1] 中华人民共和国自然资源部.《中国矿产资源报告2022》.北京:地质出版社,2022,9.

[2] 何满潮,高玉兵,盖秋凯,杨军.无煤柱自成巷力学原理及其工法[J].煤炭科学技术,2023,51(01):19-30.DOI:10.13199/j.cnki.cst.2022-1850.

[3] 中国工程院“能源中长期发展战略研究”项目组.中国能源中长期(2030,2050)发展战略研究:节能·煤炭卷[M].科学出版社,2011.

[4] 胡炳南.条带开采中煤柱稳定性分析[J].煤炭学报,1995(02):205-210.

[5] 刘贵,张华兴,徐乃忠.深部厚煤层条带幵采煤柱的稳定性[J],煤炭学报,2008,10:1085-1091

[6] Singh R, Singh T N, Dhar B B. Coal pillar loading in shallow mining conditions[C]//International journal of rock mechanics and mining sciences & geomechanics abstracts. Pergamon, 1996, 33(8): 757-768.

[7] Khair A W, Peng S S. Causes and mechanisms of massive pillar failure in a southern West Virginia coal mine[J]. Prepr., Soc. Min. Eng. AIME;(United States), 1983, 83(CONF-831009-).

[8] 张开智,郭周克,程秀洋等.坚硬顶板煤柱稳定性实测分析[J].煤炭科学技术,2002(04):12-15.

[9] Snodgrass J J, Newman D A. An in situ technique for the assessment of failure in coal pillars[C] . US symposium on rock mechanics. 26. 1985: 1181-1188.

[10] Lu P H. Stability evaluation of retreating longwall chain pillars with regressive integrity factors[C] . 5th ISRM Congress. OnePetro, 1983.

[11] Wang H, Poulsen B A ,Shen B, et al. The influence of roadway backfill on the coal pillar strength by numericalinvestigation[J]. International Journal of Rock Mechanics & Mining Sciences, 2011, 48(3):443-450

[12] Iannacchione A, Mark C. Evaluating coal pillar mechanics through field measurements[C] . Proceedings of the 11th international conference on ground control in mining. 1992: 38-47.

[13] Kumar R, Das A J, Mandal P K, et al. Probabilistic stability analysis of failed and stable cases of coal pillars[J]. International Journal of Rock Mechanics and Mining Sciences, 2021, 144: 104810.

[14] Mark C, Chase F E, Campoli A A. Analysis of retreat mining pillar stability[R]. West Virginia Univ., Morgantown, WV (United States), 1995.

[15] Gao W, Ge M. Stability of a coal pillar for strip mining based on an elastic-plastic analysis[J]. International Journal of Rock Mechanics and Mining Sciences, 2016, 87: 23-28.

[16] Hao Q W, Chugh Y P. An engineering approach to predict subsidence likelihood over abandoned coal mines in Illinois[C]//Proceedings of the third workshop on surface subsidence due to underground mining. 1992.

[17] 谢和平,段法兵,周宏伟,赵国旭.条带煤柱稳定性理论与分析方法研究进展[J].中国矿业,1998(05):37-41.

[18] 黄鹏. 煤岩蠕变损伤机理及工作面临空区段煤柱稳定性研究[D].中国矿业大学,2018.

[19] 胡殿科.煤柱稳定性影响因素的敏感性分析[J]. 能源技术与管理, 2016, 41(3):76-77.

[20] 安百富,张吉雄,李猛.充填回收房式采场煤柱稳定性分析[J]. 采矿与安全工程学报, 2016, 33(2): 239-243.

[21] 邓喀中,范洪冬,谭志祥等. 多煤层条带开采煤柱稳定性评价方法研究[J]. 中国科技论文在线, 2009, 4(11): 824-829.

[22] 李学华,鞠明和,贾尚昆,种照辉.沿空掘巷窄煤柱稳定性影响因素及工程应用研究[J].采矿与安全工程学报,2016,33(05):761-769.DOI:10.13545/j.cnki.jmse.2016.05.001.

[23] 贾光胜,康立军.综放开采采准巷道护巷煤柱稳定性研究[J].煤炭学报,2002,2(1):6-10.

[24] 杜君武,黄庆享.浅埋煤层群不同煤柱错距覆岩结构演化规律及煤柱稳定性分析[J].采矿与岩层控制工程学报,2022,4(01):16-24.

[25] 徐金海,缪协兴,张晓春.煤柱稳定性的时间相关性分析[J].煤炭学报,2005,04:433-436.

[26] K. E. Sizer,M. Gill. Pillar failure in shallow coal mines—a recent case history[J]. Mining Technology, 2013, 109(3):

[27] 邹友峰,柴华彬.我国条带煤柱稳定性研究现状及存在问题[J].采矿与安全工程学报, 2006(02):141-145+150.

[28] 解兴智.浅埋煤层房柱式采空区顶板-煤柱稳定性研究[J].煤炭科学技术,2014,42(07):1-4+9.

[29] 何满潮,邹友峰.条带煤柱的抗滑稳定性分析[J]水文地质工程地质,1993(6):11-14.

[30] 谢宗宝,范志忠条带煤柱稳定性及支护设计研究[J]煤炭科学技术研究, 2008,36(7):19-22.

[31] 王明立,胡炳南,程效海,张刚艳.急倾斜煤层群开采覆岩破坏与煤柱稳定性数值模拟[J].煤矿开采,2005(04):64-66+88.

[32] 李德海,赵忠明, 李东升.条带煤柱强度弹塑性理论公式的修正[J].矿治工程, 2004, 24(3): 16-17,20.

[33] 刘洋,石平五,张壮路.长壁留煤柱支撑法开采“顶板-煤柱”结构分析[J].西安科技大学学报,2006 ,26(2):161-166.

[34] 郭文兵,邓喀中,邹友峰.条带煤柱的突变破坏失稳理论研究[J].中国矿业大学学报, 2015, 34(1):77-81.

[35] 程伟,和德江,张晋京.高瓦斯压力煤层中相邻巷道支护研究[J].煤炭科学技术, 2005, 33 (7): 58-60.

[36] 戎涛,胡春红,李振华.采动影响下巷道群稳定性的现场监测研究[J].有色金属, 2009, 61(4):37-40.

[37] 杨科,谢广祥,常聚才.煤柱宽度对巷道围岩稳定性影响分析[J].地下空间与工程学报, 2009,5(5):991-995.

[38] A A 鲍里索夫. 矿山原理与计算[M].平寿康译.北京: 煤炭工业出版社, 1986.

[39] Wright FD. Mining Engineers Handbook. NewYork: Amer. Inst. Min.Met. Eng1973,80-96.

[40] M.S.Diederichs, P.K.Kaiser. Stability of large excavations in laminated hard 74 rock masses: the voussoir analogue revisited. Int. J. of Rock. Mech. and Mill.Sci, 1999, (36)(D):

[41] Sofianos A.I. Analysis and design ofan underground hard rock voussoir beam Roof. Mech. Sci. and Geomech. Abstr. 1996.

[42] 刘洋. 长壁留煤柱支撑法开采煤柱优化设计及破坏的可监测性研究[D], 陕西:西安科技大学, 2005.

[43] 常西坤.村庄下大倾角煤层条带煤柱合理尺寸研究[D], 山东:山东科技大学,2007.

[44] D.布洛克.工程断裂力学基础[M].北京:科学出版社, 1980.

[45] Wilson A H,An hypothesis concerning pillar stability.Min.Eng.,1972,131,409-417.

[46] 暴雪峰.煤柱宽度对煤巷稳定性的影响[J].西部探矿工程,2021,33(04):162-165.

[47] 石超弘,苏士杰,丁国利.深埋强冲击煤层工作面区段煤柱宽度确定[J].煤炭工程,2021,53(02):5-9.

[48] 王旭春,黄福昌,张怀新.A.H威尔逊煤柱设计公式探讨与改进[J].煤炭学报 ,2002 , 27(6): 604-608.

[49] Whittaker B N, Singh R N. Design and stability of pillars in longwall mining[J]. Min. Eng.(London);(United Kingdom), 1979, 139(214)

[50] FENG Jicheng,MA Nianjie,ZHAO Zhiqiang,etal.Width of narrow pillar of roadway driving along goaf at large height mining face in deep mine[J].Journal of Mining & Safety Engineering,2014,31 (04):580-586.

[51] 赵双全.双巷布置工作面宽煤柱留巷矿压规律研究[J].实用技术,2015,24(3):39-41.

[52] 余学义,王琦,赵兵朝,薄其山,王洪涛.大采高双巷布置工作面巷间煤柱合理宽度研究[J].岩石力学与工程学报,2015,34(S1):3328-3336.

[53] 李庆忠.综放面小煤柱留巷理论与试验研究[D].山东科技大学,2003.

[54] Du B, Liu C, Yang J, et al. Abutment pressure distribution pattern and size optimization of coal pillar under repeated mining: a case study[J]. Arabian Journal of Geosciences, 2020, 13(23): 1261.

[55] Liu J, Jiang F, Wang N, et al. Research on reasonable width of segment pillar of fully mechanized caving face in extra-thick coal seam of deep shaft[J]. 2012.

[56] 谷拴成,张志飞,杨超凡,袁增云,霍小泉.考虑煤岩体成拱效应的工作面区段煤柱合理尺寸研究[J].中国安全生产科学技术,2021,17(09):77-83.

[57] 王建利. 浅埋薄基岩窄煤柱巷道上覆岩层破断规律与稳定控制研究[D].中国矿业大学,2017.

[58] 侯敬宗.走向条带煤柱稳定性及条采覆岩运动的初步分析[J]辽宁工程技术大学学报, 1988(s1):58-60.

[59] Wang R, Bai J, Yan S, et al. An innovative approach to theoretical analysis of partitioned width & stability of strip pillar in strip mining[J]. International Journal of Rock Mechanics and Mining Sciences, 2020, 129: 104301.

[60] 刘洋.基于抛物线型强度准则的巷道煤柱塑性区宽度确定[J].煤炭工程, 2016, 48(12): 83-86.

[61] 李东升,李德海,宋常胜.条带煤柱设计中极限平衡理论的修正应用[J]辽宁工程技术大学学报,2003,22(1):7-9.

[62] 于洋,邓喀中,范洪冬.条带开采煤柱长期稳定性评价及煤柱设计方法[J].煤炭学报,2017,42(12):3089-3095.DOI:10.13225/j.cnki.jccs.2017.0645.

[63] 任建喜,王东星,王江等.浅埋煤层大采高区段煤柱合理宽度留设研究[J].煤炭技术,2016,35(09):1-3.

[64] 杜江涛.近距离采空区下综放工作面窄煤柱尺寸优化设计[J].煤炭工程,2019,51(07):11-14.

[65] 涂敏,林远东,张向阳等.大空间孤岛采场覆岩结构演化与区段煤柱合理宽度研究[J].采矿与安全工程学报,2021,38(05):857-865.

[66] 张宇,李炜博,杨少雄.浅埋煤层孤岛工作面合理区段煤柱宽度研究[J].山东煤炭科技,2021,39(12):15-17.

[67] Fan N, Wang J, Zhang B, et al. Reasonable width of segment pillar of fully-mechanized caving face in inclined extra-thick coal seam[J]. Geotechnical and Geological Engineering, 2020, 38: 4189-4200.

[68] 张宏,姜泽,樊建宇,李竹.基于Salamon模型的采空区应力响应特征及区段煤柱合理留设宽度研究[J].矿业研究与开发,2022,42(09):79-83.DOI:10.13827/j.cnki.kyyk.2022.09.009.

[69] 谷拴成,王博楠,黄荣宾,苗彦平.综采面末采段回撤通道煤柱荷载与宽度确定方法[J].中国矿业大学学报,2015,44(06):990-995.

[70] 张智敏. 采高与厚硬岩层对侧向煤体应力分布及巷道围岩稳定性的影响研究[D].太原理工大学,2022.

[71] 陆士良. 中国煤矿巷道围岩控制[M].中国矿业大学出版社,1994.

[72] 徐志强. 杭来湾煤矿30104上工作面支承压力分布规律及区段煤柱尺寸优化研究[D].西安科技大学,2018.

[73] 龙驭球.弹性地基梁的计算[M].人民教育出版社,1981.