煤田地质与勘探2024，Vol.52Issue(8)：101-110,10.DOI:10.12363/issn.1001-1986.24.03.0218
蒙陕接壤区典型煤层开采顶板周期性变形破坏及涌水响应特征
Periodic roof deformation and failure and associated water inflow characteristics during the mining of typical coal seams in the Inner Mongolia-Shaanxi contiguous area
摘要
Abstract
[Objective]The disturbance of coal mine mining damages the aquifer/aquiclude structures of the overburden,causing concentrated water inflow and further affecting safe production in mines.[Methods]Using methods of the phys-ical simulation of similar materials,numerical simulation,and on-site in situ monitoring,this study investigated the wa-ter inflow during the mining of the dominant 3-1 coal seam,typically influenced by water in sandstones on the coal seam roof,in the Inner Mongolia-Shaanxi contiguous area.By comparing the measured data of mines with similar geological and mining conditions in the surrounding area,this study delved into the periodic evolutionary patterns of both the coal support pressure and the vertical displacement of the overburden in the goaf during the mining of typical mining faces of the 3-1 coal seam.Accordingly,this study quantitatively analyzed the variations of microseismic events at the moment of periodic roof weighting on the laboratory scale.Finally,this study comprehensively determined the development char-acteristics of the hydraulically conductive fracture zones on the coal seam roof with mining,along with the trend of wa-ter inflow from the roof varying with the periodic weighting of the overburden.[Results and Conclusions]Key find-ings are as follows:(1)With the mining face advancement,the overburden exhibited a step distance of about 40 m in the initial weighting and of 12-28 m in periodic weighting.At the moment of the overburden fracturing,the periodic weight-ing of surrounding rocks first increased and then stabilized.As the mining face advanced to the fifth periodic weighting(advancement distance:140 m),the advanced support pressure peaked,with the peak vertical displacement of the over-burden at the moment of both periodic weighting and fracturing showing zigzag-shaped variations with coal mining.Similarly,comprehensive indicators,such as displacement monitoring data,total energy of microseismic events,and event frequency,indicate that at the moment of the fifth periodic weighting,the vertical displacement amplitude of the overburden peaked,while the height of the plastic zone remained roughly stable.(2)The hydraulically conductive frac-ture zone,with a maximum height of about 120 m,would be directly connected to the sandstone aquifer of the Zhiluo Formation on the coal seam roof.The groundwater inflow with coal mining manifested two wavy changing trends.The groundwater inflow displayed stepped growth with a long cycle of about 800 m on the global scale of the mining face but,locally,exhibited oscillatory changes with short cycles of 16-48 m and a strong correlation with the weighting peri-od of the overburden.The findings of this study provide a reference for both the prediction of the water inflow of min-ing faces and the arrangement of the water prevention and drainage system.关键词
蒙陕接壤区/水害防治/涌水量变化/顶板破坏/周期来压/数值模拟/微震Key words
Inner Mongolia-Shaanxi contiguous area/prevention and control of water hazards/change in water inflow/roof failure/periodic weighting/numerical simulation/microseism分类
矿业与冶金引用本文复制引用
周振方,王昱同,王同,董书宁,董阳,罗生虎,薛建坤,王治宙,王淑璇,尚宏波,王甜甜..蒙陕接壤区典型煤层开采顶板周期性变形破坏及涌水响应特征[J].煤田地质与勘探,2024,52(8):101-110,10.基金项目
天地科技股份有限公司科技创新创业资金专项重点项目(2022-2-TD-ZD005) （2022-2-TD-ZD005）
陕西省青年科技新星项目(2023KJXX-094) （2023KJXX-094）
陕西省自然科学基础研究计划重点项目(2023-JC-ZD-27) （2023-JC-ZD-27）
国家自然科学基金项目(41807221) （41807221）
