基于倾斜煤层采动覆岩卸压边界模型的渗透率空间分布规律  

Spatial distribution law of permeability based on the mining-induced stress relief boundary model of inclined coal seam in overlying strata

作　　者：张碧川 邹全乐[2,3] 冯增朝[1] 朱南南 冉启灿 陈子涵 刘佳奇[1] 蔡婷婷 杨雪林 ZHANG Bichuan;ZOU Quanle;FENG Zengchao;ZHU Nannan;RAN Qican;CHEN Zihan;LIU Jiaqi;CAI Tingting;YANG Xuelin(Key Laboratory of In-Situ Property-Improving Mining of Ministry of Education,Taiyuan University of Technology,Taiyuan,Shanxi 030024,China;State Key Laboratory of Coal Mine Disaster Dynamics and Control,Chongqing University,Chongqing 400044,China;School of Resources and Safety Engineering,Chongqing University,Chongqing 400044,China;China Coal Research Institute,Beijing 100013,China;College of Safety and Emergency Management Engineering,Taiyuan University of Technology,Taiyuan,Shanxi 030024,China)

机构地区：[1]太原理工大学原位改性采矿教育部重点实验室,山西太原030024 [2]重庆大学煤矿灾害动力学与控制全国重点实验室,重庆400044 [3]重庆大学资源与安全学院,重庆400044 [4]煤炭科学技术研究院有限公司,北京100013 [5]太原理工大学安全与应急管理工程学院,山西太原030024

出　　处：《岩石力学与工程学报》2025年第3期638-650,共13页Chinese Journal of Rock Mechanics and Engineering

基　　金：山西省基础研究计划面上项目(202303021221009);山西省基础研究计划青年项目(202203021212238)。

摘　　要：为掌握基于倾斜煤层采动覆岩卸压边界模型的覆岩渗透率空间分布规律,以地表沉降与采空区两侧煤壁应力分布特征为媒介,通过地表沉降与覆岩应力分布的对应关系并结合覆岩卸压边界定义,采用理论推导的方法确定了不同倾角煤层覆岩卸压边界,基于3DEC数值模拟并结合Python二次开发获得覆岩渗透率空间分布规律。结果表明:随着煤层倾角由0°增加30°,采空区高位侧卸压范围由原来的38.4 m增加至54.5 m,采空区两侧煤壁应力集中位置应力差由0 MPa增加至13.1 MPa,应力集中位置向低位侧移动了0.4 m,使得低位侧卸压边界扩展;采空区中部应力恢复位置向低位侧移动28.3 m,导致中部卸压边界下移,覆岩最大渗透率由90 mD增加到270 mD。研究表明:卸压边界模型可以很好地描述覆岩不同位置卸压程度及相应的渗透率空间分布,为卸压瓦斯优势抽采区域的准确辨识提供了参考。To explore the permeability distribution of overlying strata based on the mining-induced stress relief boundary model in inclined coal seams.With surface subsidence and the stress distribution characteristics of coal walls of the goaf as the medium,based on the correspondence between surface subsidence and overlying strata,then combined with the definition of stress relief boundary,the distribution characteristics of overlying strata relief boundary at different dip angles were determined by theoretical derivation.In addition,the permeability spatial distribution law is obtained through 3DEC numerical simulation and Python secondary development.The results show that with the increase of the coal seam dip angle from 0°to 30°,the stress difference between two sides of the coal walls increases from 0 MPa to 13.1 MPa,and the stress relief region increases from the original 38.4 m to 54.5 m in higher side of the goaf.The stress concentration position shifted by 0.4 m in lower side of the goaf,thus,the stress relief boundary of lower side expanded.While the stress recovery position moved to the low side by 28.3 m in the central goaf,thus,stress relief boundary of goaf moved downward,and the maximum permeability increased from 90 mD to 270 mD in overlying strata.The stress relief boundary model can describe the stress relief degree and the corresponding spatial distribution of permeability well in overlying strata,which provides a reference for the accurate dominant gas drainage area identification.

关 键 词：采矿工程 倾斜煤层 采动应力 卸压边界 瓦斯运移 覆岩移动 

分 类 号：TD32[矿业工程—矿井建设]