Experimental study on Brazilian split test and acoustic emission characteristics of high temperature granite under different cooling methods
High-temperature rock cooling can occur in the whole process of the drilling, fracturing, and heat exchange during the geothermal energy exploitation in hot dry rock. To reveal the evolution law of rock damage, based on the Brazilian splitting test and acoustic emission technology, the effects of di...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | zho |
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Editorial Department of Bulletin of Geological Science and Technology
2022-05-01
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| Series: | 地质科技通报 |
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| Online Access: | https://dzkjqb.cug.edu.cn/en/article/doi/10.19509/j.cnki.dzkq.2021.0028 |
| _version_ | 1797277520674947072 |
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| author | Yachao Wang Bin Dou Yong Yu Jun Zheng Hong Tian Hejuan Liu |
| author_facet | Yachao Wang Bin Dou Yong Yu Jun Zheng Hong Tian Hejuan Liu |
| author_sort | Yachao Wang |
| collection | DOAJ |
| description | High-temperature rock cooling can occur in the whole process of the drilling, fracturing, and heat exchange during the geothermal energy exploitation in hot dry rock. To reveal the evolution law of rock damage, based on the Brazilian splitting test and acoustic emission technology, the effects of different high temperatures and cooling methods on the tensile properties of granite were studied. The results showed that: ①The tensile strength of granite decreases with increasing temperature from 25℃ to 600℃, and the temperature threshold, at which it decreases greatly, is advanced to 200℃ after cooling with water. After 500℃, the tensile strength is more sensitive to water cooling. ②When the load reaches the peak value, the cumulative ringing count of acoustic emission suddenly increases, and the fracture zone forms in the rock sample. Under the influence of water cooling, the ringing count peak value and energy peak value of the rock sample decrease, which indirectly reflects that the internal cracks of the rock are more developed, and both of their decrease range is larger at 200~300℃. The granite is more sensitive to heat treatment at 300℃ and after 500℃. ③With the increase in temperature, the fracture surface of granite changes from flat to rough and tortuous, from brittle to ductile; Cooling in water promotes rock fracture and advances the temperature range from brittleness to ductility. The research results provide a theoretical reference for the stability evaluation of high-temperature rocks in geothermal exploitation. |
| first_indexed | 2024-03-07T15:49:36Z |
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| id | doaj.art-ac39f545a8a646bfaf7b961904c09156 |
| institution | Directory Open Access Journal |
| issn | 2096-8523 |
| language | zho |
| last_indexed | 2024-03-07T15:49:36Z |
| publishDate | 2022-05-01 |
| publisher | Editorial Department of Bulletin of Geological Science and Technology |
| record_format | Article |
| series | 地质科技通报 |
| spelling | doaj.art-ac39f545a8a646bfaf7b961904c091562024-03-05T03:01:14ZzhoEditorial Department of Bulletin of Geological Science and Technology地质科技通报2096-85232022-05-0141320020710.19509/j.cnki.dzkq.2021.0028dzkjtb-41-3-200Experimental study on Brazilian split test and acoustic emission characteristics of high temperature granite under different cooling methodsYachao Wang0Bin Dou1Yong Yu2Jun Zheng3Hong Tian4Hejuan Liu5School of Engineering, China University of Geosciences(Wuhan), Wuhan 430074, ChinaSchool of Engineering, China University of Geosciences(Wuhan), Wuhan 430074, ChinaSchool of Engineering, China University of Geosciences(Wuhan), Wuhan 430074, ChinaSchool of Engineering, China University of Geosciences(Wuhan), Wuhan 430074, ChinaSchool of Engineering, China University of Geosciences(Wuhan), Wuhan 430074, ChinaInstitute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, ChinaHigh-temperature rock cooling can occur in the whole process of the drilling, fracturing, and heat exchange during the geothermal energy exploitation in hot dry rock. To reveal the evolution law of rock damage, based on the Brazilian splitting test and acoustic emission technology, the effects of different high temperatures and cooling methods on the tensile properties of granite were studied. The results showed that: ①The tensile strength of granite decreases with increasing temperature from 25℃ to 600℃, and the temperature threshold, at which it decreases greatly, is advanced to 200℃ after cooling with water. After 500℃, the tensile strength is more sensitive to water cooling. ②When the load reaches the peak value, the cumulative ringing count of acoustic emission suddenly increases, and the fracture zone forms in the rock sample. Under the influence of water cooling, the ringing count peak value and energy peak value of the rock sample decrease, which indirectly reflects that the internal cracks of the rock are more developed, and both of their decrease range is larger at 200~300℃. The granite is more sensitive to heat treatment at 300℃ and after 500℃. ③With the increase in temperature, the fracture surface of granite changes from flat to rough and tortuous, from brittle to ductile; Cooling in water promotes rock fracture and advances the temperature range from brittleness to ductility. The research results provide a theoretical reference for the stability evaluation of high-temperature rocks in geothermal exploitation.https://dzkjqb.cug.edu.cn/en/article/doi/10.19509/j.cnki.dzkq.2021.0028high temperature granitecooling mehtodbrazilian split testacoustic emissionthermal damage |
| spellingShingle | Yachao Wang Bin Dou Yong Yu Jun Zheng Hong Tian Hejuan Liu Experimental study on Brazilian split test and acoustic emission characteristics of high temperature granite under different cooling methods 地质科技通报 high temperature granite cooling mehtod brazilian split test acoustic emission thermal damage |
| title | Experimental study on Brazilian split test and acoustic emission characteristics of high temperature granite under different cooling methods |
| title_full | Experimental study on Brazilian split test and acoustic emission characteristics of high temperature granite under different cooling methods |
| title_fullStr | Experimental study on Brazilian split test and acoustic emission characteristics of high temperature granite under different cooling methods |
| title_full_unstemmed | Experimental study on Brazilian split test and acoustic emission characteristics of high temperature granite under different cooling methods |
| title_short | Experimental study on Brazilian split test and acoustic emission characteristics of high temperature granite under different cooling methods |
| title_sort | experimental study on brazilian split test and acoustic emission characteristics of high temperature granite under different cooling methods |
| topic | high temperature granite cooling mehtod brazilian split test acoustic emission thermal damage |
| url | https://dzkjqb.cug.edu.cn/en/article/doi/10.19509/j.cnki.dzkq.2021.0028 |
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