2016 Fiscal Year Final Research Report
Improvement of crack reduction technology by concrete expansion material
| Project/Area Number |
15K18156
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| Research Category |
Grant-in-Aid for Young Scientists (B)
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| Allocation Type | Multi-year Fund |
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| Research Field |
Building structures/Materials
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| Research Institution | Hiroshima University |
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Principal Investigator |
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| Project Period (FY) |
2015-04-01 – 2017-03-31
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| Keywords | コンクリート / ひび割れ制御 / 膨張材 / 収縮低減剤 / エトリンガイト / 水酸化カルシウム |
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| Outline of Final Research Achievements |
Although it was said that the expansive material contributes to the reduction of autogenous shrinkage by producing expandable hydrate such as ettringite (AFt) and calcium hydroxide (CH), this study has revealed that AFt hardly contributes to reduction of autogenous shrinkage and CH production has a greater effect in ultra high strength cement paste.
In addition, when a large amount of expansion material is used, unreacted expansion material undergoes a hydration reaction after cement paste is sufficiently cured, sometimes causing harmful cracks due to inflation pressure. These delayed expansion are caused by moisture It was revealed that it could occur even under conditions that were not sufficiently supplied, and the necessity of setting an upper limit on the amount of expanding material used was reconfirmed.
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| Free Research Field |
コンクリート工学
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