Study on the Self–Bearing Mechanism and Mechanical Properties of Gangue Slurry under Overburden Loading
The mining of coal resources is accompanied by a large amount of solid waste such as gangue, which seriously affects the ecological environment. The gangue grouting backfilling technique can achieve the dual goals of gangue disposal and surface deformation control by injecting gangue slurry into the...
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| Format: | Article |
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MDPI AG
2024-02-01
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| Series: | Applied Sciences |
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| Online Access: | https://www.mdpi.com/2076-3417/14/4/1628 |
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| author | Sixu Liu Jianfei Xu Nan Zhou Yuzhe Zhang Chaowei Dong Zhuo Lv |
| author_facet | Sixu Liu Jianfei Xu Nan Zhou Yuzhe Zhang Chaowei Dong Zhuo Lv |
| author_sort | Sixu Liu |
| collection | DOAJ |
| description | The mining of coal resources is accompanied by a large amount of solid waste such as gangue, which seriously affects the ecological environment. The gangue grouting backfilling technique can achieve the dual goals of gangue disposal and surface deformation control by injecting gangue slurry into the underground. The bearing mechanical characteristics of gangue slurry directly affect the surface deformation control effect of the grouting backfilling technique. In this study, a loading simulation system of grouting backfilling materials was designed, uniaxial confined compression tests were conducted, and the self–bearing mechanism of large particle–sized gangue slurry with different fluidities under instantaneous and creep loading modes was investigated. Additionally, the mechanical characteristics of the compacted body (i.e., the gangue slurry after creep loading) were analyzed. The results indicate that the self–bearing process of gangue slurry can be divided into three stages: the rapid compression and drainage stage, the pore compaction and water bleeding stage, and the particle crushing and elastic–plastic deformation stage. The uniaxial compressive stress–strain curve of a compacted body can be classified into four stages: elastic stage, yield stage, reinforcement stage, and crushing stage, and the strength of the compacted body is affected by the loading time and fluidity of the slurry. When the slurry with a fluidity of 240 mm is subjected to constant pressure for 3 h, the compressive strength of the slurry reaches the maximum value of 4.98 MPa, and 13.1% stress damage occurs when the constant pressure reaches 4 h. This research provides a theoretical basis for the improvement of the proportion and bearing characteristics of gangue grouting materials. |
| first_indexed | 2024-03-07T22:44:03Z |
| format | Article |
| id | doaj.art-e77039ebd9e04e3ea8669dcebe56dcee |
| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-07T22:44:03Z |
| publishDate | 2024-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj.art-e77039ebd9e04e3ea8669dcebe56dcee2024-02-23T15:06:36ZengMDPI AGApplied Sciences2076-34172024-02-01144162810.3390/app14041628Study on the Self–Bearing Mechanism and Mechanical Properties of Gangue Slurry under Overburden LoadingSixu Liu0Jianfei Xu1Nan Zhou2Yuzhe Zhang3Chaowei Dong4Zhuo Lv5School of Mines, China University of Mining and Technology, Xuzhou 221116, ChinaSchool of Mines, China University of Mining and Technology, Xuzhou 221116, ChinaSchool of Mines, China University of Mining and Technology, Xuzhou 221116, ChinaSchool of Mines, China University of Mining and Technology, Xuzhou 221116, ChinaSchool of Mines, China University of Mining and Technology, Xuzhou 221116, ChinaSchool of Mines, China University of Mining and Technology, Xuzhou 221116, ChinaThe mining of coal resources is accompanied by a large amount of solid waste such as gangue, which seriously affects the ecological environment. The gangue grouting backfilling technique can achieve the dual goals of gangue disposal and surface deformation control by injecting gangue slurry into the underground. The bearing mechanical characteristics of gangue slurry directly affect the surface deformation control effect of the grouting backfilling technique. In this study, a loading simulation system of grouting backfilling materials was designed, uniaxial confined compression tests were conducted, and the self–bearing mechanism of large particle–sized gangue slurry with different fluidities under instantaneous and creep loading modes was investigated. Additionally, the mechanical characteristics of the compacted body (i.e., the gangue slurry after creep loading) were analyzed. The results indicate that the self–bearing process of gangue slurry can be divided into three stages: the rapid compression and drainage stage, the pore compaction and water bleeding stage, and the particle crushing and elastic–plastic deformation stage. The uniaxial compressive stress–strain curve of a compacted body can be classified into four stages: elastic stage, yield stage, reinforcement stage, and crushing stage, and the strength of the compacted body is affected by the loading time and fluidity of the slurry. When the slurry with a fluidity of 240 mm is subjected to constant pressure for 3 h, the compressive strength of the slurry reaches the maximum value of 4.98 MPa, and 13.1% stress damage occurs when the constant pressure reaches 4 h. This research provides a theoretical basis for the improvement of the proportion and bearing characteristics of gangue grouting materials.https://www.mdpi.com/2076-3417/14/4/1628gangue grouting backfillingload–bearing deformation characteristicsself–bearing mechanismmechanical strength of compacted body |
| spellingShingle | Sixu Liu Jianfei Xu Nan Zhou Yuzhe Zhang Chaowei Dong Zhuo Lv Study on the Self–Bearing Mechanism and Mechanical Properties of Gangue Slurry under Overburden Loading Applied Sciences gangue grouting backfilling load–bearing deformation characteristics self–bearing mechanism mechanical strength of compacted body |
| title | Study on the Self–Bearing Mechanism and Mechanical Properties of Gangue Slurry under Overburden Loading |
| title_full | Study on the Self–Bearing Mechanism and Mechanical Properties of Gangue Slurry under Overburden Loading |
| title_fullStr | Study on the Self–Bearing Mechanism and Mechanical Properties of Gangue Slurry under Overburden Loading |
| title_full_unstemmed | Study on the Self–Bearing Mechanism and Mechanical Properties of Gangue Slurry under Overburden Loading |
| title_short | Study on the Self–Bearing Mechanism and Mechanical Properties of Gangue Slurry under Overburden Loading |
| title_sort | study on the self bearing mechanism and mechanical properties of gangue slurry under overburden loading |
| topic | gangue grouting backfilling load–bearing deformation characteristics self–bearing mechanism mechanical strength of compacted body |
| url | https://www.mdpi.com/2076-3417/14/4/1628 |
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