Failure mechanism and its control of surrounding rock for gob-side entry driving with narrow coal pillar in the working face with goaf on both sides

被引：0

作者：

Wang E. ^{[1
,2
,3
]}

Xie S. ^{[2
]}

Chen D. ^{[2
]}

Liu R. ^{[2
]}

Feng S. ^{[2
]}

机构：

[1] School of Mine Safety, North China Institute of Science and Technology, Langfang

[2] School of Energy and Mining Engineering, China University of Mining and Technology-Beijing, Beijing

[3] Department of Civil Engineering, The University of British Columbia, Vancouver, V6T1Z4, BC

来源：

Meitan Kexue Jishu/Coal Science and Technology (Peking) | 2023年 / 51卷 / 11期

关键词：

deep soft-broken coal; gob-side entry driving with narrow coal pillar; island coal face; sub-regional joint support; surrounding rock control;

D O I：

10.12438/cst.2021-1036

中图分类号：

学科分类号：

摘要：

Aiming at the problems of controlling the large deformation and failure of surrounding rock of deep soft-broken coal roadway, the gob-side entry driving with narrow coal pillar in the working face mined on both sides of the deep soft-broken coal seam in a mine is taken as the engineering background, which is very difficult to control the surrounding rock. The main difficulties of surrounding rock of coal roadway control are analyzed, and the large deformation and failure mechanisms of surrounding rock of gob-side entry driving with narrow coal pillar are studied in FLAC3D numerical simulation software. The results show that the stress adjustment and unloading caused by the mining disturbance at the large height working face, the overlying roof load of gob-side entry driving is mainly borne by the solid coal. It is concluded that the peak stress area of surrounding rock in gob-side entry driving with narrow coal pillar is mainly located in solid coal and its depth of shoulder angle, and its vertical stress concentration factor is as high as 3.04. It is clarified that the roof shoulder angle in solid coal, coal pillar and the shallow plasticized surrounding rock in solid coal are the key control areas. It is characterized that the maximum extension range of plastic zone of roof, solid coal and coal pillar is about 5.88 m, 2.50 m and 3.00 m respectively, and the sub-regional asymmetric failure mechanisms of surrounding rock in gob-side entry driving with narrow coal pillar are revealed. The analysis clarified that the anchoring foundation of anchor cables and other supporting components should be located in a relatively complete elastic zone in the deep part of surrounding rock during roadway support. Based on this, the sub-regional combined support technology of anchor beam mesh support + channel steel anchor cable reinforcement + grouting modification is proposed. Engineering practice has proved that the high-strength support reinforcement and grouting modification measures have effectively improved the stress state of surrounding rock in gob-side entry driving with narrow coal pillar in deep coal rock mass that is soft, broken and prone to large deformation and failure, and the deformation of the roof and two sides of gob-side entry driving in the test section are controlled within 500 mm. It ensures the safe and orderly mining of the working face with large-mining height and provides a reliable way for the effective control of the large deformation of surrounding rock in such deep soft-broken coal roadway. © 2023 Meitan Kexue Jishu/Coal Science and Technology (Peking).

引用

页码：41 / 50

页数：9

共 34 条

[1] KANG Hongpu, JIANG Pengfei, YANG Jianwei, Et al., Roadway soft coal control technology by means of grouting bolts with high pressure-shotcreting in synergy in more than 1000 m deep coal mines[J], Journal of China Coal Society, 46, 3, pp. 747-762, (2021)
[2] KANG Hongpu, JIANG Pengfei, HUANG Bingxiang, Et al., Roadway strata control technology by means of bolting-modificationdestressing in synergy in 1000 m deep coal mines[J], Journal of China Coal Society, 45, 3, pp. 845-864, (2020)
[3] HUANG Bingxiang, ZHANG Nong, JING Hongwen, Et al., Large deformation theory of rheology and structural instability of the surrounding rock in deep mining roadway[J], Journal of China Coal Society, 45, 3, pp. 911-926, (2020)
[4] Jianbiao BAI, Wenlong SHEN, Guanlong GUO, Et al., Roof deformation, failure characteristics, and preventive techniques of gob-side entry driving heading adjacent to the advancing working face[J], Rock Mechanics and Rock Engineering, 48, 6, (2015)
[5] CHEN Dongdong, WANG En, XIE Shengrong, Et al., Roadway surrounding rock under multi-coal-seam mining: deviatoric stress evolution and control technology, Advances in Civil Engineering, (2020)
[6] ZHANG Kexue, ZHANG Yongjie, MA Zhenqian, Et al., Determination of the narrow pillar width of gob-side entry driving[J], Journal of Mining & Safety Engineering, 32, 3, (2015)
[7] Shengrong XIE, En WANG, Dongdong CHEN, Et al., Failure analysis and control mechanism of gob-side entry retention with a 1.7 m flexible-formwork concrete wall: a case study[J], Engineering Failure Analysis, 117, (2020)
[8] LIU Shaowei, WANG Wei, WANG Qiang, Et al., Study on stability of coal pillars of roadway excavated along gob with water in gently inclined coal seam[J], Coal Science and Technology, 48, 6, pp. 78-87, (2020)
[9] ZHAO Pengxiang, LI Gang, LI Shugang, Et al., Analysis of size effect of mechanical characteristics of coal pillars gob-side entry in inclined thick coal seam[J], Journal of Mining & Safety Engineering, 36, 6, pp. 1120-1127, (2019)
[10] WANG Dechao, LI Shucai, WANG Qi, Et al., Experimental study of reasonable coal pillar width in fully mechanized top coal caving face of deep thick coal seam[J], Chinese Journal of Rock Mechanics and Engineering, 33, 3, pp. 539-548, (2014)

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