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
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,...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | zho |
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Editorial Department of Coal Science and Technology
2023-11-01
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| Series: | Meitan kexue jishu |
| Subjects: | |
| Online Access: | http://www.mtkxjs.com.cn/article/doi/10.12438/cst.2021-1036 |
| _version_ | 1827620799519916032 |
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| author | En WANG Shengrong XIE Dongdong CHEN Ruipeng LIU Shaohua FENG |
| author_facet | En WANG Shengrong XIE Dongdong CHEN Ruipeng LIU Shaohua FENG |
| author_sort | En WANG |
| collection | DOAJ |
| description | 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. |
| first_indexed | 2024-03-09T10:54:00Z |
| format | Article |
| id | doaj.art-128a6da823154f40a71d47dfb0f309d1 |
| institution | Directory Open Access Journal |
| issn | 0253-2336 |
| language | zho |
| last_indexed | 2024-03-09T10:54:00Z |
| publishDate | 2023-11-01 |
| publisher | Editorial Department of Coal Science and Technology |
| record_format | Article |
| series | Meitan kexue jishu |
| spelling | doaj.art-128a6da823154f40a71d47dfb0f309d12023-12-01T03:36:33ZzhoEditorial Department of Coal Science and TechnologyMeitan kexue jishu0253-23362023-11-015111415010.12438/cst.2021-10362021-1036Failure mechanism and its control of surrounding rock for gob-side entry driving with narrow coal pillar in the working face with goaf on both sidesEn WANG0Shengrong XIE1Dongdong CHEN2Ruipeng LIU3Shaohua FENG4School of Mine Safety, North China Institute of Science and Technology, Langfang 065201, ChinaSchool of Energy and Mining Engineering, China University of Mining and Technology-Beijing, Beijing 100083, ChinaSchool of Energy and Mining Engineering, China University of Mining and Technology-Beijing, Beijing 100083, ChinaSchool of Energy and Mining Engineering, China University of Mining and Technology-Beijing, Beijing 100083, ChinaSchool of Energy and Mining Engineering, China University of Mining and Technology-Beijing, Beijing 100083, ChinaAiming 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.http://www.mtkxjs.com.cn/article/doi/10.12438/cst.2021-1036gob-side entry driving with narrow coal pillardeep soft-broken coalisland coal facesurrounding rock controlsub-regional joint support |
| spellingShingle | En WANG Shengrong XIE Dongdong CHEN Ruipeng LIU Shaohua FENG 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 Meitan kexue jishu gob-side entry driving with narrow coal pillar deep soft-broken coal island coal face surrounding rock control sub-regional joint support |
| title | 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 |
| title_full | 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 |
| title_fullStr | 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 |
| title_full_unstemmed | 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 |
| title_short | 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 |
| title_sort | 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 |
| topic | gob-side entry driving with narrow coal pillar deep soft-broken coal island coal face surrounding rock control sub-regional joint support |
| url | http://www.mtkxjs.com.cn/article/doi/10.12438/cst.2021-1036 |
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