Study on bearing deformation characteristics and lateral pressure distribution law of caved gangue in gob
Under the load of overlying strata, lateral pressure from the caved gangue in gob will be exerted on the support body of gob-side entry retaining or coal pillar. As time goes on, lateral pressure may lead to instability of support body of gob-side entry retaining or coal pillar, and then induce surf...
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| Format: | Article |
| Language: | zho |
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Editorial Department of Coal Science and Technology
2023-06-01
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| Series: | Meitan kexue jishu |
| Subjects: | |
| Online Access: | http://www.mtkxjs.com.cn/article/doi/10.13199/j.cnki.cst.2022-0223 |
| _version_ | 1797448836363321344 |
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| author | Hailong WANG Qi WANG Zhenhua ZHAO Quanlin FENG |
| author_facet | Hailong WANG Qi WANG Zhenhua ZHAO Quanlin FENG |
| author_sort | Hailong WANG |
| collection | DOAJ |
| description | Under the load of overlying strata, lateral pressure from the caved gangue in gob will be exerted on the support body of gob-side entry retaining or coal pillar. As time goes on, lateral pressure may lead to instability of support body of gob-side entry retaining or coal pillar, and then induce surface collapse. In order to study the bearing deformation characteristics and lateral pressure distribution law of caved gangue in gob, a combined test device for bearing deformation of caving gangue that can measure lateral pressure is developed. The caved gangue with uniform particle size distribution of 5 − 30 mm is taken as an example. By setting the same total loading time (16 h), the same target load (10 MPa) and the different number of loading levels (1, 2, 4), the bearing deformation characteristics, lateral pressure distribution law and particle size change of caving gangue before and after test are studied. The test results indicated that: Along with the increase of axial load, the axial deformation of caved gangue increases gradually, the residual bulking coefficient and porosity decrease gradually, which are more obvious in loading stage than in constant loading stage. In the early constant loading stage, the axial deformation of caved gangue grows rapidly, and then tends to be slow and steady gradually, if no strain surge occurs, the relationship between strain and time meets the logarithmic relationship. With the same target load and total loading time, as the number of loading levels increases, the total strain generated in constant loading stage increases significantly, and is 3.02%, 9.07%, 17.72% respectively, which indicates that the total energy input of caved gangue decreases with the increase of loading level number, but it plays a significant role in promoting the sliding filling and structural adjustment of caved gangue. The lateral pressure coefficient of caved gangue increases obviously with the increase of load. Caved gangue body shows strong reduction effect of load transfer and the value of load acting on caved gangue body decreases progressively from top to bottom. In the process of bearing deformation of caved gangue, the total amount of caved gangue with 5～10 mm particle size is in dynamic equilibrium. The research results have certain guiding significance for mining subsidence control. |
| first_indexed | 2024-03-09T14:17:12Z |
| format | Article |
| id | doaj.art-dd9b8a4a65434121b47bf02bf0136565 |
| institution | Directory Open Access Journal |
| issn | 0253-2336 |
| language | zho |
| last_indexed | 2024-03-09T14:17:12Z |
| publishDate | 2023-06-01 |
| publisher | Editorial Department of Coal Science and Technology |
| record_format | Article |
| series | Meitan kexue jishu |
| spelling | doaj.art-dd9b8a4a65434121b47bf02bf01365652023-11-29T01:40:25ZzhoEditorial Department of Coal Science and TechnologyMeitan kexue jishu0253-23362023-06-01516202910.13199/j.cnki.cst.2022-02232022-0223Study on bearing deformation characteristics and lateral pressure distribution law of caved gangue in gobHailong WANG0Qi WANG1Zhenhua ZHAO2Quanlin FENG3School of Civil Engineering and Architecture, Linyi University, Linyi 276000, ChinaState Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology-Beijing, Beijing 100083, ChinaNo.801 Hydrogeology and Engineering Geological Brigade of Shandong Provincial Bureau of Geology and Mineral Resources, Jinan 250014, ChinaNo.801 Hydrogeology and Engineering Geological Brigade of Shandong Provincial Bureau of Geology and Mineral Resources, Jinan 250014, ChinaUnder the load of overlying strata, lateral pressure from the caved gangue in gob will be exerted on the support body of gob-side entry retaining or coal pillar. As time goes on, lateral pressure may lead to instability of support body of gob-side entry retaining or coal pillar, and then induce surface collapse. In order to study the bearing deformation characteristics and lateral pressure distribution law of caved gangue in gob, a combined test device for bearing deformation of caving gangue that can measure lateral pressure is developed. The caved gangue with uniform particle size distribution of 5 − 30 mm is taken as an example. By setting the same total loading time (16 h), the same target load (10 MPa) and the different number of loading levels (1, 2, 4), the bearing deformation characteristics, lateral pressure distribution law and particle size change of caving gangue before and after test are studied. The test results indicated that: Along with the increase of axial load, the axial deformation of caved gangue increases gradually, the residual bulking coefficient and porosity decrease gradually, which are more obvious in loading stage than in constant loading stage. In the early constant loading stage, the axial deformation of caved gangue grows rapidly, and then tends to be slow and steady gradually, if no strain surge occurs, the relationship between strain and time meets the logarithmic relationship. With the same target load and total loading time, as the number of loading levels increases, the total strain generated in constant loading stage increases significantly, and is 3.02%, 9.07%, 17.72% respectively, which indicates that the total energy input of caved gangue decreases with the increase of loading level number, but it plays a significant role in promoting the sliding filling and structural adjustment of caved gangue. The lateral pressure coefficient of caved gangue increases obviously with the increase of load. Caved gangue body shows strong reduction effect of load transfer and the value of load acting on caved gangue body decreases progressively from top to bottom. In the process of bearing deformation of caved gangue, the total amount of caved gangue with 5～10 mm particle size is in dynamic equilibrium. The research results have certain guiding significance for mining subsidence control.http://www.mtkxjs.com.cn/article/doi/10.13199/j.cnki.cst.2022-0223caved ganguebearing deformationlateral pressurereduction effect of load transferparticle size |
| spellingShingle | Hailong WANG Qi WANG Zhenhua ZHAO Quanlin FENG Study on bearing deformation characteristics and lateral pressure distribution law of caved gangue in gob Meitan kexue jishu caved gangue bearing deformation lateral pressure reduction effect of load transfer particle size |
| title | Study on bearing deformation characteristics and lateral pressure distribution law of caved gangue in gob |
| title_full | Study on bearing deformation characteristics and lateral pressure distribution law of caved gangue in gob |
| title_fullStr | Study on bearing deformation characteristics and lateral pressure distribution law of caved gangue in gob |
| title_full_unstemmed | Study on bearing deformation characteristics and lateral pressure distribution law of caved gangue in gob |
| title_short | Study on bearing deformation characteristics and lateral pressure distribution law of caved gangue in gob |
| title_sort | study on bearing deformation characteristics and lateral pressure distribution law of caved gangue in gob |
| topic | caved gangue bearing deformation lateral pressure reduction effect of load transfer particle size |
| url | http://www.mtkxjs.com.cn/article/doi/10.13199/j.cnki.cst.2022-0223 |
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