Study on the performance of resistance to freeze-thaw of concrete coated with organosilicon hydrophobic agents

摘要

It is one of the anticorrosion measures of reinforced concrete that the concrete surface coated with organosilicon hydrophobic agents such as silane. In this paper two kinds of water cement ratio (W/C) 0.4 and 0.6 of concrete were selected, silane (isooctyl triethoxysilane) and epoxy resin coating were adopted, and the fresh water and 3.5%NaCl solution were set as mediums for freezing and thawing test. The cycle number of freezing and thawing test of concrete treated with silane is 23 more than that of untreated concrete in 0.4 W/C, and that is 25 more in 0.6 W/C. The number of freezing and thawing test cycles of concrete treated with silane in fresh water is 47 more cycles than that in NaCl solution in 0.4 W/C, and that is 40 more cycles in 0.6 W/C. The larger the water cement ratio, the worse the performance of resistance to freezing and thawing of concrete is. The damage degree of concrete in NaCl solution is more serious than that in fresh water. The results show that the performance of resistance to freeze-thaw of treated concrete with epoxy coating is not improved. The performance of resistance to freezing and thawing of concrete can be significantly improved by coating silane on the concrete at the same water cement ratio, but the damage cannot be prevent finally during freezing and thawing. The damage mechanism of treated concrete was discussed during freeze-thaw process.