Experimental Study on Mix Design of Chloride Resistant Cementitious Spacers

Abstract:

Chloride resistant HPC and protective cover are two basic measurements to improve the durability of concrete in chloride environment. Though it provides crucial cover for concrete to resist chloride ions, spacer has limited chloride resistant ability, which is overlooked by past researchers. Cementitious spacers are easy access for chloride ions to penetrate into concrete resulting in reduction of structural durability. To improve cementitious spacers’ performance, a systematic study was conducted. Test results showed that there was major difference between mortar and concrete in terms of chloride coulomb electric flux but minor difference in terms of chloride ion diffusion coefficient, which implied using chloride ion diffusion coefficient as spacer’s durability indicator was preferable; parameters of mix design had a similar influence on mortar and concrete and, with the same mixing parameters, the strength and chloride resistant ability of mortar were weaker than concrete’s; it was feasible to develop the mix design of chloride resistant cementitious spacers based on concrete’s design method with certain adjustments, such as using stricter mix proportion, adding small-size coarse aggregate, lowering water-binder ratio and optimizing the binder proportion, to achieve higher strength and durability.

• Periodical: Key Engineering Materials (Volumes 629-630)
• Pages: 351-357
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.629-630.351
• Online since: October 2014
• Authors: Chen Huang, Wen Ying Guo*, Yi Bo Yang, Hui Zhao, Zhen Jie Li, Jian Kuan Li, Jian Yong Bao, Heng Chang Wang
• Keywords: Cementitious Spacers, Chloride-Resisting, Mix Design

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