Laws and prevention methods of ground cracks in shallow coal seam mining

Authors

HOU Enke, College of Geology and Environment, Xi’an University of Science and Technology, Xi’an 710054, China; Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi’an 710054, ChinaFollow
XIE Xiaoshen, College of Geology and Environment, Xi’an University of Science and Technology, Xi’an 710054, China; Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi’an 710054, China
FENG Dong, College of Geology and Environment, Xi’an University of Science and Technology, Xi’an 710054, China; Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi’an 710054, China
CHEN Qiuji, College of Geomatics, Xi’an University of Science and Technology, Xi’an 710054, China
CHE Xiaoyang, College of Safety Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, China
HOU Pengfei, College of Geology and Environment, Xi’an University of Science and Technology, Xi’an 710054, China; Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi’an 710054, China

Abstract

The large-scale and high-intensity mining of shallow coal seams in northern Shaanxi has induced serious ground collapse, resulting in land damage in large area, water and soil loss, and vegetation death, and thus leading to the epigenetic environment degradation. In order to understand the development law of ground collapse and fracture in shallow coal seam mining, clarify its mechanism, and put forward the appropriate treatment and restoration measures to realize the coordinated development of “coal-water-ecology”, Zhangjiamao mine field and Ningtiaota mine field in northern Shaanxi were taken as the study area. On this basis, the development law and control methods of ground collapse in shallow coal seam mining were studied by means of field investigation, simulation experiment and theoretical analysis. As shown in the results, the ground fractures in shallow coal seam mining are distributed in “O” shape, and the static development characteristics are positively correlated with mining height, topography and geomorphology, but negatively correlated with mining depth. Besides, the ground fractures are most developed near the cutting hole of the same working face, followed by the roadway, and least developed in the face. The ground fracture has two characteristics of activity: “opening first and then (half) closing” and “only opening”. The activity lasts 4-9 days in general. During the activity period, the initial fracture width has a linear positive correlation with the maximum development width, and has a linear and exponential positive correlation with the stable width. The ground fracture activity of mining in the downslope section of the loess gully region is related to the stability coefficient of the topsoil block, while the stability coefficient is negatively correlated with the slope toe but positively correlated with the main fracture spacing by a first power function. The activity of “opening first and then (half) closing” of mining slope fractures in the uphill section is controlled by rock block inversion and slope slip, and the activity characteristics of in-plane gulley bottom fractures are controlled by the migration of key rock strata. In this paper, the treatment method of “fracture filling-gulley restoration” was proposed for the penetrating fractures in the bottom of gully and “fracture filling+micro-topography reconstruction” for slope fractures in loess gully region. In addition, the “three-ring” restoration mode was studied for the collapse area in sand beach. The research results have been applied in Anshan Coal Mine and Ningtiaota Coal Mine with good results.

Keywords

shallow coal seam, ground collapse, development law, collapse treatment, ecological restoration and demonstration

DOI

10.12363/issn.1001-1986.22.05.0427

Recommended Citation

HOU Enke, XIE Xiaoshen, FENG Dong, et al. (2022) "Laws and prevention methods of ground cracks in shallow coal seam mining," Coal Geology & Exploration: Vol. 50: Iss. 12, Article 5.
DOI: 10.12363/issn.1001-1986.22.05.0427
Available at: https://cge.researchcommons.org/journal/vol50/iss12/5

Reference

[1] 王双明,孙强,乔军伟,等. 论煤炭绿色开采的地质保障[J]. 煤炭学报,2020,45(1):8−15

WANG Shuangming,SUN Qiang,QIAO Junwei,et al. Geological guarantee of coal green mining[J]. Journal of China Coal Society,2020,45(1):8−15

[2] 康红普,徐刚,王彪谋,等. 我国煤炭开采与岩层控制技术发展40 a及展望[J]. 采矿与岩层控制工程学报,2019,1(1):013501

KANG Hongpu,XU Gang,WANG Biaomou,et al. Forty years development and prospects of underground coal mining and strata control technologies in China[J]. Journal of Mining and Strata Control Engineering,2019,1(1):013501

[3] 徐祝贺,李全生,李晓斌,等. 浅埋高强度开采覆岩结构演化及地表损伤研究[J]. 煤炭学报,2020,45(8):2728−2739

XU Zhuhe,LI Quansheng,LI Xiaobin,et al. Structural evolution of overburden and surface damage caused by high–intensity mining with shallow depth[J]. Journal of China Coal Society,2020,45(8):2728−2739

[4] 范立民. 榆神府矿区煤炭开采与地质灾害研究[J]. 中国煤炭,2014,40(5):52−55

FAN Limin. On coal mining intensity and geo-hazard in Yulin-Shenmu-Fugu mine area[J]. Journal of China Coal,2014,40(5):52−55

[5] 侯恩科,陈育,车晓阳,等. 浅埋煤层过沟开采覆岩破坏特征及裂隙演化规律研究[J]. 煤炭科学技术,2021,49(10):185−192

HOU Enke,CHEN Yu,CHE Xiaoyang,et al. Study on overburden failure characteristics and fracture evolution law of shallow buried coal seam through trench mining[J]. Coal Science and Technology,2021,49(10):185−192

[6] 钱鸣高,许家林. 煤炭开采与岩层运动[J]. 煤炭学报,2019,44(4):973−984

QIAN Minggao,XU Jialin. Behaviors of strata movement in coal mining[J]. Journal of China Coal Society,2019,44(4):973−984

[7] 王双明,侯恩科,谢晓深,等. 中深部煤层开采对地表生态环境的影响及修复提升途径研究[J]. 煤炭科学技术,2021,49(1):19−31

WANG Shuangming,HOU Enke,XIE Xiaoshen,et al. Study on influence of surface ecological environment caused by middle deep coal mining and the ways of restoration[J]. Coal Science and Technology,2021,49(1):19−31

[8] 胡振琪,王新静,贺安民. 风积沙区采煤沉陷地裂缝分布特征及发生发育规律[J]. 煤炭学报,2014,39(1):11−18

HU Zhenqi,WANG Xinjing,HE Anmin. Distribution characteristic and development rules of ground fissures due to coal mining in windy and sandy region[J]. Journal of China Coal Society,2014,39(1):11−18

[9] XU Yuankun,WU Kan,LI Liang,et al. Ground cracks development and characteristics of strata movement under fast excavation:A case study at Bulianta Coal Mine,China[J]. Bulletin of Engineering Geology and the Environment,2019,78(1):325−340.

[10] 侯恩科,首召贵,徐友宁,等. 无人机遥感技术在采煤地面塌陷监测中的应用[J]. 煤田地质与勘探,2017,45(6):102−110

HOU Enke,SHOU Zhaogui,XU Youning,et al. Application of UAV remote sensing technology in monitoring of coal mining−induced subsidence[J]. Coal Geology & Exploration,2017,45(6):102−110

[11] 侯恩科,谢晓深,王双明,等. 中埋深煤层综采地表裂缝发育规律研究[J]. 采矿与安全工程学报,2021,38(6):1178−1188

HOU Enke,XIE Xiaoshen,WANG Shuangming,et al. Development law of ground cracks induced by fully–mechanized mining of medium–buried coal seams[J]. Journal of Mining & Safety Engineering,2021,38(6):1178−1188

[12] 侯恩科，张杰，谢晓深，等. 无人机遥感与卫星遥感在采煤地表裂缝识别中的对比[J]. 地质通报，2019，38(2/3)：443–448.

HOU Enke，ZHANG Jie，XIE Xiaoshen，et al. Contrast application of unmanned aerial vehicle remote sensing and satellite remote sensing technology relating to ground surface cracks recognition in coal mining area[J]. Geological Bulletion of China，2019，38(2/3)：443–448.

[13] 胡振琪. 再论土地复垦学[J]. 中国土地科学,2019,33(5):1−18

HU Zhenqi. Re-exploration of land reclamation science[J]. China Land Science,2019,33(5):1−18

[14] 刘辉,邓喀中,雷少刚,等. 采动地裂缝动态发育规律及治理标准探讨[J]. 采矿与安全工程学报,2017,34(5):884−890

LIU Hui,DENG Kazhong,LEI Shaogang,et al. Dynamic developing law and governance standard of ground fissures caused by underground mining[J]. Journal of Mining & Safety Engineering,2017,34(5):884−890

[15] 胡海峰,廉旭刚,蔡音飞,等. 山西黄土丘陵采煤沉陷区生态环境破坏与修复研究[J]. 煤炭科学技术,2020,48(4):70−79

HU Haifeng,LIAN Xugang,CAI Yinfei,et al. Study on ecological environment damage and restoration for coal mining–subsided area in loess hilly area of Shanxi Province[J]. Coal Science and Technology,2020,48(4):70−79

[16] DAI Zhangyin,ZHANG Lu,WANG Yanlei,et al. Deformation and failure response characteristics and stability analysis of bedding rock slope after underground adverse slope mining[J]. Bulletin of Engineering Geology and the Environment,2021,80:4405−4422.

[17] 朱恒忠. 西南山区浅埋煤层采动地裂缝发育规律及减损控制[D]. 北京：中国矿业大学(北京)，2019.

ZHU Hengzhong. Developmental regularity and reduction control technology of mining−induced ground fissures of shallow burial coal seam in mountainous area of southwestern China[D]. Beijing：China University of Mining and Technology (Beijing)，2019.

[18] 钱鸣高，石平五，许家林. 矿山压力与岩层控制[M]. 徐州：中国矿业大学出版社，2010.

[19] 黄庆享,曹健,贺雁鹏. 浅埋极近采空区下工作面顶板结构及支架载荷分析[J]. 岩石力学与工程学报,2018,37(增刊1):3153−3159

HUANG Qingxiang,CAO Jian,HE Yanpeng. Analysis of structure and support load of mining face under ultra-close goaf in shallow multiple seams[J]. Chinese Journal of Rock Mechanics and Engineering,2018,37(Sup.1):3153−3159

[20] 张强,杨康,张昊,等. 固体充填开采矿压显现弱化规律及表征研究[J]. 中国矿业大学学报,2021,50(3):479−488

ZHANG Qiang,YANG Kang,ZHANG Hao,et al. Research on weakening law and quantitative characterization of strata behavior in solid filling mining[J]. Journal of China University of Mining & Technology,2021,50(3):479−488

[21] 范立民,马雄德,蒋泽泉. 保水采煤研究30年回顾与展望[J]. 煤炭科学技术,2019,47(7):1−30

FAN Limin,MA Xiongde,JIANG Zequan. Review and thirty years prospect of research on water-preserved coal mining[J]. Coal Science and Technology,2019,47(7):1−30

[22] HUANG Qingxiang,DU Junwu. Coupling control on pillar stress concentration and surface cracks in shallow multi-seam mining[J]. International Journal of Mining Science and Technology,2020,31(1):95−101.

[23] 侯恩科,冯栋,谢晓深,等. 浅埋煤层沟道采动裂缝发育特征及治理方法[J]. 煤炭学报,2021,46(4):1297−1308

HOU Enke,FENG Dong,XIE Xiaoshen,et al. Development characteristics and treatment methods of mining surface cracks in shallow–buried coal seam gully[J]. Journal of China Coal Society,2021,46(4):1297−1308