Original paper(Vol.49 No.7 pp.799)

Influence of Solvent Free Silane on Hydrophobicity of Concrete

Yoshimori Kubo, Atsushi Hattori, Soyoaki Kurihara and Toyoaki Miyagawa

Abstract:From the viewpoint of deterioration mechanism of concrete structures, water is one of the most important factor. Many kinds of surface treatments have been used to control water content of concrete. Surface treatments can be classified into two types based on water control of concrete. One type allows no movement of water into or out of concrete. The other type is hydrophobic treatment which restricts water penetration into concrete, but allows water vapour to move out. The former treatments may promote deterioration due to water remained in concrete. Thus, the silane treatments which are typical hydrophobic treatments have better performance as repair method. Recently, the use of solvent free silanes have been investigated because of safety of application and less influence on environment. In this study, hydrophobic performance of concrete treated with solvent free silanes was investigated. Furthermore, the influence of molecular structure and active ingredient content of silane on hydrophobic performance was investigated. The silanes of larger molecular weight had the better performance. Silane of molecular weight 262, which get larger impregnation content and hydrophobic layer, had the best hydrophobic performance. The influence of active ingredient content of silane of molecular weight 262 on the hydrophobic performance was not significant.

Key Words:Solvent free silane, Molecular structure of silane, Active ingredient content of silane, Hydrophobic performance, Surface treatment