浅埋煤层群开采覆岩垮落及导水裂隙带发育规律研究  

Development of overlying strata collapse and water-conducting fractured zone in shallow coal seams mining

作　　者：尚慧[1] 柳思航 甘智慧 苏理想 刘阳 SHANG Hui;LIU Sihang;GAN Zhihui;SU Lixiang;LIU Yang(College of Geology and Environment,Xi’an University of Science and Technology,Xi’an,Shaanxi 710054,China;Exploration Institute,Guangdong Bureau of Coal Geology,China National Administration of Coal Geology,Guangzhou,Guangdong 510400,China;Shaanxi Mining Development Industry and Trade Co.Ltd.,Xi’an,Shaanxi 710054,China)

机构地区：[1]西安科技大学地质与环境学院,陕西西安710054 [2]中国煤炭地质总局广东煤炭地质局勘查院,广东广州510400 [3]陕西矿业开发工贸有限公司,陕西西安710054

出　　处：《水文地质工程地质》2025年第2期125-137,共13页Hydrogeology & Engineering Geology

基　　金：国家自然科学基金项目(41702377);陕西省自然科学基础研究计划项目(2017JQ4008)。

摘　　要：浅埋煤层群井下开采对上覆岩层有较大影响,不仅会加剧地表沉陷,而且可能造成地表和地下水流失,影响生态环境和发展安全。为进一步掌握浅埋煤层群开采过程中覆岩垮落规律和裂隙分布特征,以宁夏石嘴山二矿2^(#)、3^(#)、5^(#)和6^(#)煤层为研究对象,分别采用相似材料模拟试验、数值模拟和经验公式计算,分析导水裂隙带发育规律;同时采用相似材料模拟试验方法,分析一次采动和多次采动覆岩垮落规律。研究结果表明:(1)浅埋近距离煤层群开采时,上层煤周期来压步距大于下层;(2)单层煤开采时,上覆岩层垮落以“铰接结构”和“台阶结构”形式出现,两层及多层煤开采时,“铰接结构”稳定性明显降低,垮落结构主要以“台阶结构”稳定在采空区上方;(3)一次采动时形成“梯形”裂隙区,二次采动时形成“M”形裂隙区,多次采动时形成两个“等腰梯形”裂隙区;(4)导水裂隙带发育高度一次采动时呈平稳增长—缓慢变化趋势,重复采动时,导水裂隙带发育高度则呈快速增长—平稳增长趋势;(5)相似材料模拟试验值及数值模拟结果与实测值较为接近,且均符合煤矿防治水规定。该结果可为类似矿区煤层群高效开采提供参考依据。Shallow underground mining of coal seams has significant impacts on the overlying rock formations,not only exacerbating surface subsidence but also potentially leading to surface and groundwater loss,thereby affecting the development and safety of the ecological environment.To further understand the collapse law and fracture distribution characteristics of overlying strata during the shallow coal seam mining process,a study was conducted on the 2^(#),3^(#),5^(#),and 6^(#)coal seams of the Shizuishan No.2 Mine in Ningxia.Similar material simulation tests,numerical simulations,and empirical formula calculations were employed to analyze the development of water-bearing fracture zones and the collapse characteristic of the overlying strata under single and multiple mining operations.The results indicate that:(1)During the mining of shallow and closely spaced coal seams,the gob-side entry retention time of the upper coal seam is greater than that of the lower coal seam.(2)When mining a single coal seam,the collapse of the overlying strata occurs in the form of“hinged structure”and“step structure”.As to the mining of two or more coal seams,the stability of the“hinged structure”decreases significantly and the collapse structure mainly stabilizes as a“step structure”above the goaf.(3)During the initial mining,a“trapezoidal”fracture zone is formed,while during the secondary mining,an“M-shaped”fracture zone is formed,and during multiple mining operations,two“isosceles trapezoidal”fracture zones are formed.(4)The development height of the water-bearing fracture zone shows a steady increase or slow change during the initial mining.While during repetitive mining,the development height of the water-bearing fracture zone shows a rapid increase to steady growth.(5)The values obtained from the similar material simulation tests and numerical simulations are similar to the measured values,and all of them comply with the regulations for coal mine water control.These results can provide a basis for the eff

关 键 词：煤层群 覆岩垮落 导水裂隙带 相似材料模拟 数值模拟 

分 类 号：TD325[矿业工程—矿井建设]