Enhancing carbonated mortar durability by electro-osmotic treatment of silane

Electro-osmotic treatment (EOT) of silane for enhancing the durability of carbonated mortar was investigated. During the EOT, silane was injected into carbonated mortar pores by applying an electric field, leading to deeper penetration depths. The durability enhancements of the carbonated mortar after EOT of silane were evaluated by examining water absorption, carbonation depth, sulfate resistance and chloride diffusion. The microscopic mechanism of the electro-injected silane treatment was determined by X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectroscopy. The results indicated that the resistance to water absorption, sulfate diffusion and chloride diffusion were improved by the EOT of silane. The silane treatment had a limited impact on carbonation resistance. An impervious film with a dense structure was formed in the carbonated mortar through the EOT of silane, and this treatment did not introduce new crystal phases to the hydration products within the carbonated mortar.