The mechanism of chloride ion penetration of concrete in cold region assuming actual environment

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K18131
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Civil engineering materials/Construction/Construction management
• Research Institution: Hachinohe Institute of Technology
• Principal Investigator: Sakoi Yuki 八戸工業大学, 大学院工学研究科, 准教授 (30453294)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: コンクリート / 複合劣化 / 耐久性 / 凍結融解 / 塩化物イオン浸透性

Outline of Final Research Achievements

In this study, the chloride ion penetration into concrete that assumed the actual environment was examined. For the concrete received various environmental action, like a freezing- thawing, drying- wetting or pre-penetration of a chloride ion into concrete, the chloride ion penetration into concrete that received several environmental action and its mechanism were examined in this study.
From the result of this study, it was found that the chloride ion penetration into concrete that was subjected to environmental action was accelerated compare with that of normal condition, even though the surface deterioration did not occurred. It is considered that this phenomenon is due to move the water in hardened concrete. This result means that the influence of the water movement in hardened concrete according to environmental action does not ignore for the deterioration prediction of concrete in cold region.

Free Research Field

コンクリート材料

Academic Significance and Societal Importance of the Research Achievements

近年，コンクリート構造物の耐久性向上および維持管理の重要性が高まっている。一方で，寒冷地域におけるコンクリート構造物は，凍結融解作用や乾湿繰返し，融雪剤の散布に起因する塩化物イオンの浸透とそれに伴う鉄筋の腐食など，種々の環境作用が複合的に作用することによって，早期劣化が生じている。これらの維持管理において，環境作用を考慮した劣化予測が必要不可欠となる。本研究課題の成果は，環境作用を考慮したコンクリート中への塩化物イオン浸透性を検討したものであり，既存構造物の耐久性予測・維持管理計画の立案において基礎的資料となり得るものである。