Interface and anti-corrosion properties of sea-sand concrete with fumed silica

The present study investigates the influence of fumed silica on the formation mechanism of Friedel's salt of the concrete made with dredged sea-sand, containing high chloride content. We have observed significant differences in the measured silicon and aluminum content, which changed the interfacial response of as-prepared concrete. The fumed silica was migrated from the cement matrix and diffused to the concrete interface, which induced H+ evolution reaction due to Al-OH groups. Hence, the enhanced compressive strength and lower porosity and ion permeability of modified concrete have been obtained. The fracture modes of concrete, with and without fumed silica have also been discussed. These results provide the possibility of using non-desalination dredged sea-sand, for concrete preparation and attain the optimized production efficiency and performance of sea-sand concrete. Furthermore, the choice of one-electron oxidized species of additives provide a mechanistic insight into the formation of Friedel's salt assisted sea-sand concrete production.