2022 Fiscal Year Final Research Report
Experimental study on the effect of temperature history on the lifetime properties of concrete structures
Project/Area Number |
19K04695
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Multi-year Fund |
Section | 一般 |
Review Section |
Basic Section 23010:Building structures and materials-related
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Research Institution | Tokyo City University |
Principal Investigator |
SATO SACHIE 東京都市大学, 建築都市デザイン学部, 准教授 (70408714)
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Project Period (FY) |
2019-04-01 – 2023-03-31
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Keywords | 構造体コンクリート / 強度発現 / 温度履歴 |
Outline of Final Research Achievements |
In order to evaluate the lifetime performance of concrete structures, the strength development, the amount of hydration products formed, and the physical properties were investigated, especially with respect to the high-temperature history that occurs in the early age of the concrete. It was found that hydration products increase with high-temperature history, but CSH(II) with a high C/S ratio tends to be formed, and the Vickers hardness of CSH is low compared to that of CH. Therefore, CSH does not generally enhance compressive strength. In addition, the effect of maximum temperature was evaluated by analyzing the structural strength development of high-strength concrete using a machine learning model, and it was found that a high-temperature history up to 28 days of age can be a factor for strength enhancement, but it can be a factor for strength reduction at later ages.
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Free Research Field |
建築構造材料
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Academic Significance and Societal Importance of the Research Achievements |
本研究の成果により、実施工現場において異なる季節環境で施工され硬化するコンクリート部材が温度履歴を受けた際の品質変化メカニズムを明らかにすることができた。これをもとに、より精緻な性能予測モデルを作成することが可能と考えられ、近年多様化する使用材料や調合設計についてより省力化した合理的な設計手法を提案できると考えられる。学術的には、既往の文献で示された高温履歴時の空隙構造の変化が強度発現に影響するとの知見に対してより詳細にそのメカニズムを示すことができた。
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