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Title |
Formwork-Type Nondestructive Method to Evaluate Concrete Segregation
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Authors |
배영환(Young Hwan Bae) ; 임홍재(Hong Jae Yim) |
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DOI |
https://doi.org/10.4334/JKCI.2023.35.1.071 |
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Keywords |
고유동 콘크리트; 콘크리트 재료분리; 비파괴 평가; 전기비저항; 거푸집 self-consolidation concrete; concrete segregation; nondestructive evaluation; electrical resistivity; formwork |
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Abstract |
Self-consolidating concrete, which is widely used in complex structures, is vulnerable to placement failure. Concrete segregation can be a resulting problem, and immediate evaluation is required before curing to prevent strength degradation and to ensure durability. A conventional method used to assess concrete segregation involves the wet-sieving of fresh concrete in order to measure settled coarse aggregate in a column-type mold. However, this method is limited in that changed coarse aggregate in a mixture hardly affects the changed mix-proportion of water, cement, and fine aggregate. This work proposes a nondestructive method based on the measurement of electrical resistivity in fresh concrete. Various types of concrete samples were prepared with varying amounts of superplasticizer to induce segregation and different size distribution of used coarse aggregate so that the coarse aggregate effect in segregation could be studied. As a result, nondestructive measurement was performed, and the applicability of the proposed method was verified by comparison with the results of wet-sieving tests.
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