A Study on the Chloride Migration Properties of High Durable Marine Concrete Using the Expansion Production Admixture

팽창재를 혼입한 고내구성 해양콘크리트의 염화물 확산특성에 관한 연구

Recently, high strength, flowability, and durability of concrete were required according to increase of large scale and high rise structure. However, cracks occurred easily on the high performance concrete. In this reason, using expansion agent for reducing shrinkage cracks were increased, but it did not consider on durability of high performance concrete. Accordingly, this study1 investigated the resistance of shrinkage and damage form salt by mixing CSA expansion agent on the blast-furnace slag cement and mixed cement for the low heat of hydration by three components. The cases that 8% of expansion agent was mixed and the proportion was OPC were expanded till 43.7 times compared with control concrete. For the resistance to the damage of salt, it was improved when mixing ratio was incresed and the maximum size of coarse aggregate growed bigger. In this study, the resistance to the damage of salt of the cases that 8% of expansion agent was mixed was improved about 16% compared with control concrete.

본 연구에서는 고로슬래그 혼합시멘트와 3성분계 저발열 혼합시멘트를 대상으로 하고, 여기에 CSA계 팽창재를 혼입함으로서 이에 따른 수축보상 효과와 함께 염해저항 특성에 미치는 영향에 대하여 검토하였다. 검토결과, 배합조건이 OPC이고, 팽창재 혼입율이 8%인 경우는 팽창재를 혼입하지 않은 경우에 비해 최대 43.7배까지팽창하는 것으로 평가되었고, 굵은골재 최대치수가 콘크리트의 길이변화특성에 미치는 영향은 적은 것으로 나타났다. 염해저항성은 굵은골재 최대치수가 클수록, 그리고 팽창재 혼입율이 증가할수록 개선되는 것으로 평가되었는데, 본 연구범위에서는 팽창재를 8% 혼입한 콘크리트의 염해저항성이 팽창재를 혼입하지 않은 경우에 비해 약 16% 정도 유리한 것으로 평가되었다.