A study on ultrasonic attenuation mechanism in crystalline rock core sample
| Project/Area Number |
26420459
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Multi-year Fund |
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| Section | 一般 |
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| Research Field |
Structural engineering/Earthquake engineering/Maintenance management engineering
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| Research Institution | Okayama University |
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Principal Investigator |
Kimoto Kazushi 岡山大学, 環境生命科学研究科, 准教授 (30323827)
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| Co-Investigator(Renkei-kenkyūsha) |
NISHIYAMA Satoshi 岡山大学, 環境生命科学研究科, 教授 (00324658)
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| Project Period (FY) |
2014-04-01 – 2017-03-31
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| Project Status |
Completed (Fiscal Year 2016)
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| Budget Amount *help |
¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000)
Fiscal Year 2016: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
Fiscal Year 2015: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
Fiscal Year 2014: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000)
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| Keywords | 結晶質岩 / 超音波 / 表面波 / 散乱 / 減衰 / 弾性波 / 群速度 / 花崗岩 / き裂 |
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| Outline of Final Research Achievements |
In this study, ultrasonic measurements and the signal processing were carried out aiming to understand the elastic wave propagation characteristics in a highly heterogeneous crystalline rock core samples. For the ultrasonic measurements, PZT and laser Doppler vibrometer were used. With the measurement setup, longitudinal (L), shear(S) and Rayleigh surface(R) waves transmitted through a cylindrical granite samples were measured. It was shown as the result, that the granite core behaves as an acoustically orthotropic material which can support a ballistic waves having the frequency components up to 500kHz. Another important finding is that the grain boundaries act as a relatively weak scatterer while strong scattering occurs at more sparsely distributed micro cracks.
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Report
(4 results)
Research Products
(11 results)
