Influence of Fly Ash as Cement Replacement on Chloride Penetration and Frost Resistance of Recycled Concrete

Abstract:

The influence of fly ash as cement replacement on pore structure, chloride penetration and frost resistance of recycled concrete is investigated by evaporable water test, chloride natural diffusion test, and freeze-thawing test. The experimental results indicate that adding fly ash to recycled concrete can decrease its porosity and improve its pore size distribution. Chloride penetration resistance of recycled concrete is enhanced firstly and then reduced with increasing of fly ash content. The best proportion replacing cement with fly ash is 20%. Fly ash content has a certain influence on the frost resistance of recycled concrete, and the frost resistance of recycled concrete only has been improved when the proportion of fly ash replacing cement achieves more than 20%.

• Periodical: Advanced Materials Research (Volumes 250-253)
• Pages: 1031-1037
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.250-253.1031
• Online since: May 2011
• Authors: Xiang Hao Wu, Pan Yuan, Yan Tao Jiao
• Keywords: Chloride Penetration, Fly Ash (FA), Freezing-Thawing Cycle, Pore Structure, Recycled Concrete (RC)

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