Estimation method for durability performance in cover concrete adversely affected by segregation

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K18100
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Civil engineering materials/Construction/Construction management
• Research Institution: Ehime University
• Principal Investigator: Kawaai Keiyu 愛媛大学, 理工学研究科(工学系), 講師 (90725631)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 不均質さ / 耐久性能 / 透気係数 / 含水率 / 酸素透過 / 腐食形態

Outline of Final Research Achievements

This study examined the effect of heterogeneity of cover concrete caused by segregation on the resistance against ingress of substances. Air permeability coefficients tended to increase in upper parts of column specimens cast with OPC mixture with typical bleeding water. Based on the results of air permeability and moisture content obtained up to the age of 180 days of monitoring, this study showed that the durability estimation technique based on the relationship between two variables can be applied to assess the heterogeneity such as porous structures formed owing to bleeding water in a form of segregation in column specimen. On the other hand, the ingress of chloride ions tended to increase in those regions affected by bleeding water, which partly contribute to higher microcell corrosion current density. It should be noted that total corrosion current density was likely to increase with higher rate of oxygen permeability measured via cathodic polarization in this study.

Free Research Field

コンクリート工学