Durability and purification performance of concrete impregnated with silicate and sprayed with photocatalytic TiO2.

Highlights • Enhanced durability performance in silicate-surface impregnated concrete. • SEM analysis for quantitative surface analyzing. • Considerations of submerged and spraying period of silicate and TiO 2. • Verification of durability and mechanical performance through surface impregnation. • Verification of self-cleaning and self-purification through TiO 2. Abstract This paper proposes an integrated concrete surface treatment with surface enhancement via silicate impregnation and surface spraying with TiO 2 (a photocatalyst). In this work, two types of silicate-based materials, sodium alumina silicate (SAS) and colloidal silica (COS) were used. Various tests were carried out to characterize the silicate properties and engineering performance of the impregnated concrete. In addition, the purification performance in concrete sprayed with TiO 2 was investigated. Concrete impregnated with silicate and sprayed with TiO 2 showed an improvement in the durability and mechanical performance because of the addition of the CSH gel and TiO 2 barrier. After impregnation, the TiO 2 applied by spraying retained good performance for the removal of acetaldehyde and methyl orange. [ABSTRACT FROM AUTHOR]