Project/Area Number |
01550444
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
Building structures/materials
|
Research Institution | Kyushu University |
Principal Investigator |
OHKUBO Takaaki Kyushu Univ. Dept. of Architecture Assoc. Prot., 工学部, 助教授 (60185220)
|
Co-Investigator(Kenkyū-buntansha) |
NAKATAKE Mikio Kyushu Univ. Dept. of Architecture Assistant, 工学部, 教務員 (30101174)
HARADA Shizuo Kyushu Univ. Dept. of Architecture Assoc. Research, 工学部, 助手 (40198916)
MATSUFUJI Yasunori Kyushu Univ. Dept. of Architecture Prot., 工学部, 教授 (20037922)
|
Project Period (FY) |
1989 – 1990
|
Project Status |
Completed (Fiscal Year 1990)
|
Budget Amount *help |
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1990: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1989: ¥1,600,000 (Direct Cost: ¥1,600,000)
|
Keywords | Hot Weather / Hot Weather Concrete / Ambient Temperature / Humidity / Temperature Distribution / Vaporized Water / Hydration Heat / Heat Loss due to Vaporization / 養生 / コンクリ-ト |
Research Abstract |
In order to establish an acceptable quality standard of the hot weather concrete, it is essential that such problems are at first analyzed and evaluated and then the sources of the respective problems are identified. In this study, the crack occurrence in the early time in the concrete placed in a hot weather environment was discussed from the viewpoint of the temperature distribution in the specimens. For the experiments, mortar specimens were prepared under various environmental conditions, being subjected to regular measurement of their internally distributed temperatures for 24 hours in order to exhibit how the both ambient air temperature over the period and end-of-mixing temperature of mortar specimen affect such internal temperature distribution. This was designed to allow us to quantitatively evaluate ambient temperature effects on crack occurrence, reflecting the fact that the hot weather concrete intrinsically relates to high ambient temperatures. Through a series of experiments it was brought to light that the relation between the ambient and end-of-mixing temperatures, heat gain due to hydration and heat loss due to vaporization significantly affected the temperature distribution in the specimens.
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