摘要
针对岩溶影响下近距离煤层的开采,以贵州某矿为研究背景,运用UDEC模拟分析了岩溶洞对覆岩运移以及采动裂隙发育的影响。结果表明:在岩溶地区双煤层开采条件下,重复采动加剧了覆岩的运移与采动裂隙发育;上煤层开采覆岩下沉量最大值为3 m,下煤层开采覆岩下沉量最大值为5.5 m,工作面通过岩溶洞下方下沉量达到最大值;重复采动下裂隙发育都经历了产生、扩张、压实3个阶段,且采动裂隙在岩溶洞处最为发育;采动造成岩溶洞的裂缝持续向周围扩展,当工作面推进经过岩溶洞下方后,采动裂隙与岩溶洞的裂缝贯通;两次采动对覆岩的应力分布都造成影响,随着开采的进行,在岩溶洞处频繁出现应力集中现象;近距离煤层重复采动下,岩溶洞对裂隙的扩展具有导向作用,采动裂隙与岩溶裂隙贯通,容易导致地下水进入工作面,对煤矿开采造成安全隐患。
Aiming at the mining of close-distance coal seams under the influence of karst,taking a mine in Guizhou as the research background,UDEC simulation was used to analyze the influence of karst caves on overburden migration and mining-induced fracture development.The results show that under the condition of two coal seams mining in karst area,repeated mining aggravates the migration of overlying strata and the development of mining fissures.The maximum subsidence of overlying strata in the upper coal seam mining is 3 m,the maximum subsidence of overlying strata in the lower coal seam mining is 5.5 m,and the maximum subsidence of the working face through the karst cave is reached.The fracture development under repeated mining has experienced three stages of generation,expansion and compaction,and the mining fracture is most developed in the karst cave.The cracks of the karst cave caused by mining continue to expand around.When the working face advances under the karst cave,the mining cracks and the cracks of the karst cave are connected.The two mining activities have an impact on the stress distribution of the overburden rock.With the progress of mining,stress concentration occurs frequently in the karst cave.Under the repeated mining of close-distance coal seams,karst caves have a guiding effect on the expansion of fissures.The mining fissures and karst fissures are connected,which easily leads to the entry of groundwater into the working face and poses a potential safety hazard to coal mining.
作者
周存柳
康向涛
胡锦国
ZHOU Cuniu;KANG Xiangtao;HU Jinguo(College of Mining,Guizhou University,Guiyang Guizhou 550025,China)
出处
《矿业研究与开发》
CAS
北大核心
2023年第12期86-93,共8页
Mining Research and Development
基金
国家自然科学基金项目(52064009)。
关键词
岩溶
近距离煤层开采
重复采动
覆岩运移
采动裂隙发育
Karst
Close distance coal seam mining
Repeated mining
Overburden rock migration
Mining fracture development
