Project/Area Number |
13450181
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
土木材料・力学一般
|
Research Institution | Kumamoto University |
Principal Investigator |
OHTSU Masayasu Kumamoto University, Graduate School of Science & Technology, Professor, 大学院・自然科学研究科, 教授 (80109016)
|
Co-Investigator(Kenkyū-buntansha) |
SHIGEISHI Mitsuhiro Kumamoto University, Faculty of Engineering, Associate Professor, 工学部, 助教授 (50253761)
|
Project Period (FY) |
2001 – 2003
|
Project Status |
Completed (Fiscal Year 2003)
|
Budget Amount *help |
¥12,600,000 (Direct Cost: ¥12,600,000)
Fiscal Year 2003: ¥2,500,000 (Direct Cost: ¥2,500,000)
Fiscal Year 2002: ¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 2001: ¥8,300,000 (Direct Cost: ¥8,300,000)
|
Keywords | Acoustic Emission / Core Test / Damage Mechanics / Compression Test / Young's Modulus / アコースティック・エミッション / 損傷力学 / アコーステイツク・エミッション / 圧縮強度 |
Research Abstract |
In recent years, the deterioration of concrete structures has been a public problem, and maintenance techniques have been subjected to intensive research. For the strategic maintenance, it is of significant importance to evaluate not only the strength of concrete but also the degree of damage in concrete. Accordingly, quantitative damage assessment of concrete is developed and proposed by applying acoustic emission (AE) technique and damage mechanics. Concrete samples damaged by freezing and thawing and carbonation processes are examined as the controlled damage. The quantitative damage evaluation based on fracturing behavior of concrete under uniaxial compression is studied. Since AE behavior of concrete is dependent on the degree of damage, a relation is formulated by the rate process analysis. Employing Loland's model, a relationship between stress and strain is modeled, and then the applicability of the damage parameter is confirmed. By calculating the relative damage, which is evaluated as the ratio of initial Young's modulus to the intact modulus, from AE rate-process analysis, the initial damage of an actual structure is estimated. The results estimated are in remarkable agreement with the actual damages in the controlled samples. Consequently, a data-base is constructed to apply the proposed method to concrete core-samples taken from existing structures.
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