摘要
随着地壳浅部易采煤炭资源的逐渐枯竭,复杂地质条件下的多煤层开采将成为新常态。由于多煤层开采对上覆岩体造成极大的重复扰动,导致覆岩的垮落、移动与裂隙演化规律相较于单一煤层开采更加复杂。为了研究多煤层下行重复采动条件下覆岩变形与裂隙演化特征,本文以陕北神府矿区张家峁煤矿4^(-2)煤层、4^(-3)煤层、4^(-4)煤层、5^(-2)煤层开采为研究对象,进行了几何相似比1∶100的相似模型试验和UDEC数值模拟研究。张家峁煤矿四层煤层下行重复采动物理相似模拟和数值模拟分析结果表明,周期来压步距随下行开采呈逐渐减小的规律,冒落带高度与煤层厚度正相关,4^(-2)煤层开采后导水裂隙带贯穿至地表,4^(-3)煤层、4^(-4)煤层、5^(-2)煤层开采结束后,导水裂隙带均贯穿层间覆岩。顶板围岩在反复拉伸、挤压作用下,破碎程度逐渐增大,且多为未闭合裂隙。研究结果可以为多煤层开采条件下的顶板管理和开采设计提供理论层面的参考和指导。
With the gradual depletion of easily exploitable coal resources in the shallow crust,multi-coal seams mining under complex geological conditions will become the new normal.As multi-coal seams mining will cause great repetitive disturbance to the overlying rock mass,resulting in a more complex collapse,movement and crack evolution law of the overburden rock compared to single-coal seam mining.In order to study the collapse,deformation and crack evolution law of overburden rock under the condition of downward repetitive mining of multi-coal seams,this paper takes the four coal seams mining of 4^(−2),4^(−3),4^(−4) and 5^(-2) in Zhangjiamao Coal Mine,Shenfu Mining District,North Shaanxi Province,as the research subject,and carries out a similar modeling experimental study and a UDEC numerical simulation model with a geometrical similarity ratio of 1∶100.The results of physical similarity simulation and numerical simulation analysis of downward repetitive mining in the fourth coal seam of Zhangjiamao Coal Mine show that the cyclic pressure step distance gradually decreases with downward mining,and the height of the caving zone is positively correlated with the thickness of the coal seam.After the mining of the 4^(−2) coal seam,the water conducting crack zone runs through the surface.After the mining of the 4^(−3),4^(−4),and 5^(-2) coal seams is completed,the water conducting crack zone runs through the interlayer overburden rock,and the fragmentation of the roof surrounding rock gradually increases under repetitive stretching and compression,and most of them are unclosed cracks.The findings of investigation can provide a theoretical level of reference and guidance for roof management and mining design under multi-coal seam mining conditions.
作者
张金贵
姬中奎
呼少平
王海
胡俭
韩强
杨帆
ZHANG Jingui;JI Zhongkui;HU Shaoping;WANG Hai;HU Jian;HAN Qiang;YANG Fan(School of Energy and Mining Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China;Xi’an Research Institute Co.,Ltd.,China Coal Technology and Engineering Group Corp.,Xi’an 710077,China;Shenmu Zhangjiamao Mining Co.,Ltd.,Shaanxi Coal Group,Shenmu 719300,China)
出处
《中国矿业》
北大核心
2024年第5期152-163,共12页
China Mining Magazine
基金
陕西省自然科学基金重点研发计划项目资助(编号:2022SF-046)
中煤科工西安研究院(集团)有限公司科技创新基金项目资助(编号:2022XAYJS06,2023XAYJS02)。
关键词
多煤层
重复采动
关键层
导水裂隙带
相似模型
multi-coal seam
repetitive mining
key stratum
water conducting crack zone
scale model test
