| Project/Area Number |
63460172
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
Building structures/materials
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| Research Institution | Nagoya University |
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Principal Investigator |
KOSAKA Yoshio Nagoya University, Professor, 工学部, 教授 (00022989)
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| Co-Investigator(Kenkyū-buntansha) |
IMAI Nobuhiro Nagoya University, Research Associate, 工学部, 助手 (00023333)
YAMADA Kazuo Aichi Institute of Technology, Associate Professor, 助教授 (10093080)
KOHAMA Yoshirou Nagoya University, Associate Professor, 工学部, 助教授 (50023304)
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| Project Period (FY) |
1988 – 1989
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| Project Status |
Completed (Fiscal Year 1989)
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| Budget Amount *help |
¥6,300,000 (Direct Cost: ¥6,300,000)
Fiscal Year 1989: ¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1988: ¥4,100,000 (Direct Cost: ¥4,100,000)
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| Keywords | Concrete / Non-Destructive Test / Quality Evaluation / Ultrasonic Spectroscopy / Elastic Wave / Propagating Characteristics / Frequency Transfer Function / Damping Properties / コンクリート / 超音波スペクトロスコピー法 |
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| Research Abstract |
Ultrasonic spectroscopy technique was applied to evaluating the quality of damaged concrete , as one of the nondestructive testing technique for concrete.
Main results were summarized as follows:
(1) Damping Characteristics of Meastred Ultrasonic Wave
1) The characteristics of measured ultrasonic waveform for mortar specimen were almost independent of the water-cement ratio, but those for concrete specimen decreased subsequently with the increase of the water-cement ratio. The obtained values of these characteristics for concrete specimen were generally smaller than those of the mortatr specimen.
2) The energy and the maximum amplitude of measured wave propagating through the mortar and concrete specimens decreased and the energy moment and the energy dispersion increased with the progressive damage of specimen. The energy of propagated wave was more sensitively affected by the damage of the internal structure of specimen than the maximumamplitude and ultrasonic pulse velocity.
(2) Damping Chacrteristics of Frequency Response
1) The frequency components of transfer function in the low frequency range became prominent significantly with the progressive damage of the mortar and concrete.
2) The maximum amplitude and the energy of frequency transfer function of mortar and concrete specimens decreased with the progressive damage of them.
(3)Applicability of Ultrasonic Spectroscopy for Evaluation of Damage of Specimen
1) The maximum amplitude, the average frequency and the energy of measured waveform, and further the particular energy of the frequency transfer function in the specific frequency range were closely related the change of internal structure of mortar and concrete specimens, due to the damage.
2) The results obtained by the present study suggested that the assessment of damage in mortar and concrete was possibly accomplished by the ultrasonic spectroscopy technique.
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