Experimental Study on the Microstructure Evolution of Mixed Disposal Paste in Surface Subsidence Areas
The integrated disposal of surface subsidence pits and surface solid waste can be realized by backfilling a surface subsidence area with a paste made from the solid wastes of mines, such as tailings and waste rock. The microstructures of these wastes determine the macroscopic properties of a paste b...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2016-05-01
|
| Series: | Minerals |
| Subjects: | |
| Online Access: | http://www.mdpi.com/2075-163X/6/2/43 |
| _version_ | 1811253542953943040 |
|---|---|
| author | Wei Sun Aixiang Wu Kepeng Hou Yi Yang Lei Liu Yiming Wen |
| author_facet | Wei Sun Aixiang Wu Kepeng Hou Yi Yang Lei Liu Yiming Wen |
| author_sort | Wei Sun |
| collection | DOAJ |
| description | The integrated disposal of surface subsidence pits and surface solid waste can be realized by backfilling a surface subsidence area with a paste made from the solid wastes of mines, such as tailings and waste rock. The microstructures of these wastes determine the macroscopic properties of a paste backfill. This paper presents an experimental study on the internal structure evolution of pasty fluid mixed with different waste rock concentrations (10%, 30%, and 50%) and cement dosages (1% and 2%) under damage. To this end, a real-time computed tomography (CT) scan is conducted using medical CT and a small loading device. Results show that UCS (uniaxial compressive strength) increases when the amount of cement increases. Given a constant amount of cement, UCS increases first and then decreases as waste rock content increases. UCS is maximized at 551 kPa when the waste rock content is 30%. The paste body is a typical medium used to investigate initial damage, which mainly consists of microholes, pores, and microcracks. The initial damages also exhibit a high degree of random inhomogeneity. After loading, cracks are initiated and expand gradually from the original damage location until the overall damages are generated. The mesostructure evolution model of the paste body is divided into six categories, and this mesostructure is reasonable when the waste rock content is 30%. |
| first_indexed | 2024-04-12T16:52:36Z |
| format | Article |
| id | doaj.art-43d1f99d8b2644b9a3481172b75eabac |
| institution | Directory Open Access Journal |
| issn | 2075-163X |
| language | English |
| last_indexed | 2024-04-12T16:52:36Z |
| publishDate | 2016-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Minerals |
| spelling | doaj.art-43d1f99d8b2644b9a3481172b75eabac2022-12-22T03:24:21ZengMDPI AGMinerals2075-163X2016-05-01624310.3390/min6020043min6020043Experimental Study on the Microstructure Evolution of Mixed Disposal Paste in Surface Subsidence AreasWei Sun0Aixiang Wu1Kepeng Hou2Yi Yang3Lei Liu4Yiming Wen5Faculty of Land Resources Engineering, Kunming University of Science and Technology, Kunming 650093, ChinaSchool of Civil and Environment Engineering, University of Science and Technology Beijing, Beijing 100083, ChinaFaculty of Land Resources Engineering, Kunming University of Science and Technology, Kunming 650093, ChinaFaculty of Land Resources Engineering, Kunming University of Science and Technology, Kunming 650093, ChinaFaculty of Land Resources Engineering, Kunming University of Science and Technology, Kunming 650093, ChinaFaculty of Mining Industry, Kunming Metallurgy College, Kunming 650033, ChinaThe integrated disposal of surface subsidence pits and surface solid waste can be realized by backfilling a surface subsidence area with a paste made from the solid wastes of mines, such as tailings and waste rock. The microstructures of these wastes determine the macroscopic properties of a paste backfill. This paper presents an experimental study on the internal structure evolution of pasty fluid mixed with different waste rock concentrations (10%, 30%, and 50%) and cement dosages (1% and 2%) under damage. To this end, a real-time computed tomography (CT) scan is conducted using medical CT and a small loading device. Results show that UCS (uniaxial compressive strength) increases when the amount of cement increases. Given a constant amount of cement, UCS increases first and then decreases as waste rock content increases. UCS is maximized at 551 kPa when the waste rock content is 30%. The paste body is a typical medium used to investigate initial damage, which mainly consists of microholes, pores, and microcracks. The initial damages also exhibit a high degree of random inhomogeneity. After loading, cracks are initiated and expand gradually from the original damage location until the overall damages are generated. The mesostructure evolution model of the paste body is divided into six categories, and this mesostructure is reasonable when the waste rock content is 30%.http://www.mdpi.com/2075-163X/6/2/43subsidencemill tailingswaste rockpaste backfillX-ray CT |
| spellingShingle | Wei Sun Aixiang Wu Kepeng Hou Yi Yang Lei Liu Yiming Wen Experimental Study on the Microstructure Evolution of Mixed Disposal Paste in Surface Subsidence Areas Minerals subsidence mill tailings waste rock paste backfill X-ray CT |
| title | Experimental Study on the Microstructure Evolution of Mixed Disposal Paste in Surface Subsidence Areas |
| title_full | Experimental Study on the Microstructure Evolution of Mixed Disposal Paste in Surface Subsidence Areas |
| title_fullStr | Experimental Study on the Microstructure Evolution of Mixed Disposal Paste in Surface Subsidence Areas |
| title_full_unstemmed | Experimental Study on the Microstructure Evolution of Mixed Disposal Paste in Surface Subsidence Areas |
| title_short | Experimental Study on the Microstructure Evolution of Mixed Disposal Paste in Surface Subsidence Areas |
| title_sort | experimental study on the microstructure evolution of mixed disposal paste in surface subsidence areas |
| topic | subsidence mill tailings waste rock paste backfill X-ray CT |
| url | http://www.mdpi.com/2075-163X/6/2/43 |
| work_keys_str_mv | AT weisun experimentalstudyonthemicrostructureevolutionofmixeddisposalpasteinsurfacesubsidenceareas AT aixiangwu experimentalstudyonthemicrostructureevolutionofmixeddisposalpasteinsurfacesubsidenceareas AT kepenghou experimentalstudyonthemicrostructureevolutionofmixeddisposalpasteinsurfacesubsidenceareas AT yiyang experimentalstudyonthemicrostructureevolutionofmixeddisposalpasteinsurfacesubsidenceareas AT leiliu experimentalstudyonthemicrostructureevolutionofmixeddisposalpasteinsurfacesubsidenceareas AT yimingwen experimentalstudyonthemicrostructureevolutionofmixeddisposalpasteinsurfacesubsidenceareas |