Salt scaling resistance and microstructure analysis of fly-ash cement-based concrete treated with different surface penetrants

Abstract To enhance the maintenance effect of penetrants on concrete surfaces, the impact of three types of concrete surface penetrants (lithium silicate solution (Type-L), sodium silicate solution (Type-A), and silane (Type-B)) applied on fly-ash cement-based concrete surfaces was studied. Four different dosages were used. The initial curing of concrete included water-curing and seal-curing. The salt freeze-thaw experiment and mercury intrusion porosimetry (MIP) experiment were conducted using the specimens. The results showed that the pore volume with a pore diameter above 200 nm in water-cured concrete was lower than that in seal-cured concrete. The salt-scaling resistance was also more optimal for the water-cured concrete compared with the seal-cured concrete. The applicability of penetrants under different curing conditions and the most appropriate dosages were determined. The Type-A and Type-B composite penetrants exhibited an excellent scaling resistance.