正断层区段异形煤柱护巷矿压显现特征及控制  

Characteristics and control of strong underground pressure appear under irregular section normal fault roadway pillar

作　　者：姚强岭[1] 王夫榕 马守龙 郑闯凯 李纪宝 夏泽[1] 李英虎 落弘业 吴城乐 YAO Qiangling;WANG Furong;MA Shoulong;ZHENG Chuangkai;LI Jibao;XIA Ze;LI Yinghu;LUO Hongye;WU Chengle(Key Laboratory of Deep Coal Resource Mining,Ministry of Education,China University of Mining and Technology,Xuzhou,Jiangsu221116,China;China Coal Xinji Energy Company Limited,Huainan,Anhu2i32001,China)

机构地区：[1]中国矿业大学深部煤炭资源开采教育部重点实验室,江苏徐州221116 [2]中煤新集能源股份有限公司,安徽淮南232001

出　　处：《采矿与安全工程学报》2022年第6期1095-1107,共13页Journal of Mining & Safety Engineering

基　　金：江苏省研究生科研与实践创新计划项目(KYCX21_2343);中国矿业大学研究生创新计划项目(2021WLJCRCZL009);国家自然科学基金项目(51874285)。

摘　　要：断层区段煤柱宽度及采动下断层活化程度与被保护巷道围岩稳定性密切相关。以山东枣庄矿区某矿3#煤层正断层区段异形煤柱为例,依据正断层区段异形煤柱护巷条件下采场覆岩结构特征,提出应力调整与支护相结合的围岩稳定性控制技术思路,并基于此将异形煤柱划分为2个区域。其中,区域Ⅰ为下盘回采巷道未卸压区及上盘邻近巷道“两帮+顶板”加强支护区(40~35m宽煤柱);区域Ⅱ为下盘回采巷道切顶卸压区及上盘邻近巷道“煤柱+顶板”加强支护区(35~12m宽煤柱),建立“分区卸压+分区支护”的技术体系;针对卸压区,提出一种通过布置顶板密集钻孔构造非连续人工弱化带以调整巷道围岩应力分布的方法,基于弹性理论与围岩结构“S-R”原理,确定密集钻孔切顶参数,并据此构建正断层区段异形煤柱FLAC^(3D)数值计算模型,以揭示切顶卸压前后侧向支承压力演化规律;此外,结合围岩赋存特征与应力演化特点,提出针对性的分区补强支护方案并成功应用于现场。现场应用结果显示:区域Ⅰ内邻近巷道两帮移近量达653mm,顶底板移近量在643~690mm之间,矿压显现较为剧烈,断层煤柱宽度与巷道围岩变形特征负相关;区域Ⅱ内邻近巷道前段两帮移近量较区域Ⅰ降低了38%~77%,中后段未见明显变形破坏,且断层煤柱宽度与巷道围岩变形特征正相关,卸压效果显著,表明该技术思路可有效控制断层区段异形煤柱巷道围岩变形;同时提出一种煤柱留设宽度优化思路,可为该矿类似条件下区段煤柱留设提供借鉴,且对解决采动强矿压巷道围岩控制具有重要的应用价值。The width of fault coal pillar and activation degree of fault under mining are closely related to the stability of protected roadway surrounding rock Taking the irregular section normal fault coal pillar in 3coal seam of a mine in Zaozhuang mining area of Shandong province as an example,according to the structural characteristics of overburden strata in stope under the protection of roadway by irregular section coal normal fault pillar the stability control technique of surrounding rock combining stress adjustment and support was proposed. The irregular section coal pillar was divided into two regions based on this and the technical system of“zoned pressure relief+partition support”was established. Besides,areaⅠwas the unrelieved area of footwall mining roadway and“two sides+roof”strengthened support area(coal pillar in 40-35m)of adjacent roadway and areaⅡwas the top-cutting pressure relief zone of the footwall mining roadway and“coal pillar+roof”strengthened support zone(coal pillar in 35-12m)of adjacent roadway. Aiming at the pressure relief zone,a method to adjust stress distribution of roadway surrounding rock by arranging dense boreholes in the roof to construct a discontinuous artificial weakening zone was first proposed. Based on elastic theory and“S-R”principle of surrounding rock structure,the roof cutting parameters of dense boreholes were determined,resulting in the FLAC^(3D) numerical model of irregular section coal pillar was constructed and the evolution law of lateral abutment pressure before and after roof cutting was revealed. In addition,combined with the characteristics of surrounding rock occurrence and stress evolution,a targeted zonal reinforcement support scheme was proposed and successfully applied to the site. The field application results have shown that:in areaⅠ,the two sides of adjacent roadways moved nearly 653mm,the roof and floor moved close to 643-690mm,the mine pressure was more severe and the width of coal pillar was negatively correlated with the deformatio

关 键 词：断层区段异形煤柱 顶板密集钻孔 分区卸压 分区支护 煤柱留设 

分 类 号：TD322[矿业工程—矿井建设]