Use of no-fines concrete as a building material: Strength, durability properties and corrosion protection of embedded steel

Abstract

Although no-fines concrete has been generally used for paving applications, it could be considered in other non-structural applications, such as reinforced panels, thanks to its acoustic, thermal and permeability properties. In this work, mechanical, durability-related properties and the protection provided by no-fines concrete to embedded steel against carbonation-induced corrosion have been investigated on mixtures with compressive strength in the range 7–30MPa. Additional protections, such as a mixed-in hydrophobic admixture, the coating of cement paste on the reinforcing bar or the use of galvanized or stainless steel bars, are also considered. Results show that, although no-fines concrete is susceptible to fast carbonation and it cannot provide long-term passivation to embedded steel, it may prevent corrosion in elements exposed to the atmosphere and sheltered by rain. In case of frequent contact with water, additional protections are required, preferably based on the use of corrosion resistant bars.