| Project/Area Number |
06650527
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
構造工学・地震工学
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| Research Institution | Tokai University |
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Principal Investigator |
KITAHARA Michihiro Tokai University, Marine Science and Technology, Professor, 海洋学部, 教授 (60135522)
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| Project Period (FY) |
1994 – 1995
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| Project Status |
Completed (Fiscal Year 1995)
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| Budget Amount *help |
¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 1995: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 1994: ¥1,200,000 (Direct Cost: ¥1,200,000)
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| Keywords | Interface / Crack / Ultrasonics / Nondestructive Evaluation |
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| Research Abstract |
The results of the study are summarized as follows.
1. A method to calculate the scattering amplitude was completed by the following three steps of 1) free field calculation, 2) calculation of crack-opening displacements, and 3) far-field calculation.
2. A formula to evaluate the length of the interface crack was obtained by introducing the high-frequency approximation to the crack-opening displacements. From this formula, the crack length is estimated by measuring the periodicity of the scattering amplitude.
3. The range of applicability was investigated for the formula obtained in the step 2. It was confirmed that the formula is applicable not only figh-frequency but low-frequency range.
4. The periodicity of the scattering amplitude was measured experimentally and it was introduced into the crack estimation formula derived in the step 2. The crack length estimated by formula was in good agreement with the real crack length.
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