中埋深煤层综采地表裂缝发育规律研究  

Development law of ground cracks induced by fully-mechanized mining of medium-buried coal seams

作　　者：侯恩科[1,2] 谢晓深 王双明 从通[3] 冯栋 陈真 HOU Enke;XIE Xiaoshen;WANG Shuangming;CONG Tong;FENG Dong;CHEN Zhen(School of Geology and Environment,Xi5 an University of Science and Technology,Xi'an,Shaanxi 710054,China;Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation,Xi'an,Shaanxi 710054,China;Xi'an Research Institute of China Coal Technology&Engineering Group Corp,Xi'an,Shaanxi 710077,China;Shaanxi Xiaobaodang Mining Corporation Limited,Yulin,Shaanxi 719302,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]陕西省煤炭绿色开发地质保障重点实验室,陕西西安710054 [3]中煤科工集团西安研究院有限公司,陕西西安710077 [4]陕西小保当矿业有限公司,陕西榆林719302

出　　处：《采矿与安全工程学报》2021年第6期1178-1188,共11页Journal of Mining & Safety Engineering

基　　金：国家自然科学基金面上项目(42177174);陕西煤业化工集团科研基金项目(2018MHKJ-B-J-24);陕西联合基金项目(2021JLM-09)。

摘　　要：为揭示陕北侏罗纪煤田中埋深工作面高强度开采诱发的地表裂缝发育规律、空间形态及深度特征,以小保当煤矿首采工作面为研究区,采用地表裂缝填图、裂缝宽度变化动态观测和裂缝示踪开挖观测等方法开展了风沙滩地区中埋深煤层高强度开采地表裂缝静态、动态演化规律及空间形态的研究。研究表明:112201工作面地表裂缝主要有边界裂缝和面内裂缝两类,前者沿平巷、切眼发育,后者于面内平行切眼发育。边界裂缝和面内裂缝宽度小于1.0cm占73%,宽度大于5.0cm仅占3%;裂缝整体发育程度较弱;面内裂缝宽度一般小于2.0cm,两侧无落差,滞后回采位置发育,平均滞后距30.14 m,滞后角84.1°;面内裂缝宽度随时间呈单峰型变化即表现为先开裂、后闭合(半闭合)型动态变化特征,平均活动时间约为7.8 d且缝宽增大和减小的时间基本相等,结合地表移动观测资料给出了裂缝活动时间T的计算公式;平行平巷边界裂缝呈"带状"分布在工作面平巷内侧56 m、外侧18 m的范围内,裂缝宽度则呈现开裂-增大直至稳定的变化特征;工作面地表裂缝空间形态分为楔形,梭形和分叉形3类,沙土层内发育深度不超过2.5m。宽度小于5 cm的裂缝在采后2个月内被风积沙自然掩埋而难觅踪迹,宽度大于5 cm的裂缝在采后6个月内大多被风积沙自然掩埋。这一研究结果对风沙滩地区生态环境治理和水资源保护具有重要参考价值。In order to reveal development law, spatial form, and depth characteristics of ground cracks induced by high-strength mining in the medium buried working face in Jurassic Coalfield in northern Shaanxi, with a first-mined working face of Xiaobaodang Coalmine in Jurassic Coalfield in northern Shaanxi as research area, static and dynamic evolution law and spatial distribution of ground cracks in high-strength coal seams mining in medium and deep coal seams in windy and sandy area were studies through ground cracks mapping, dynamic observation of the change of cracks width, and cracks tracing excavation observation. The results have shown that two kinds of ground cracks develop in working face 112201: boundary cracks and cracks within the working face. Specifically, boundary cracks develop along the trough and cut hole, while the latter develop paralleling to cut hole in the working face. The ground cracks with width less than 1.0 cm accounts for 73% and those larger than 5.0 cm accounts for 3%. Overall development of cracks is weak. Besides, the width of cracks within the working face is generally less than 2.0 cm and there is no drop on both sides. Dynamic cracks in the working face always develop behind current working location, with average lag distance of 30.14 m and lag angle of 84.1°. With advancement of working face, changes of the width of cracks within the working face present a unimodal type, i.e., cracks change dynamically by fracturing first and then closing/half closing. The process of dynamic crack takes 7.8 d averagely, and the time taken to increase of crack width is basically the same as that of decrease. On the basis of observation of surface movement, a function for the time of dynamic crack change was established. Boundary cracks parallel to groove, presenting a belt shape, are distributed in the range of 56 m from inner side and 18 m from the outside of the trough. The spatial characteristics of ground cracks within the working face were divided into three types: wedge shape, shuttle shape, and

关 键 词：中埋深煤层 地表裂缝 发育规律 空间形态 

分 类 号：TD325[矿业工程—矿井建设]