2017 Fiscal Year Final Research Report
Effect of water on the mechanism of time-dependent rock strength
Project/Area Number |
15K06221
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Geotechnical engineering
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Research Institution | National Institute of Advanced Industrial Science and Technology |
Principal Investigator |
MASUDA KOJI 国立研究開発法人産業技術総合研究所, 地質調査総合センター, 副研究部門長 (30344104)
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Project Period (FY) |
2015-10-21 – 2018-03-31
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Keywords | 岩石力学 / 岩石強度 / 摩擦強度 / 応力腐食 / アスペリティ |
Outline of Final Research Achievements |
The strengths of crustal faults are lower than those determined from laboratory measurements. Because long-term changes of rock strength cannot be directly monitored, so an explanation for fault weakening remains an unsolved problem. We showed laboratory evidence that supports the concept that long-term weakening of the rock strength is caused by microfracturing at asperity contacts, which is a result of crack growth at subcritical stress levels. We conducted a series of rock tests under the high-temperature and high-pressure conditions to accelerate reaction processes so that they were observable at laboratory time-scales. Our results suggest that long-term weakening of rock strength is related to chemical reactions that take place in the presence of water. The fluids underground has an important influence on time-dependent rock strength.
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Free Research Field |
地盤工学
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