Air void system and frost-salt scaling of concrete containing slag-blended cement

The experimental investigation on the frost-salt scaling resistance of air-entrained concrete containing CEM II/B-S 42.5N and CEM III/A 42.5N-HSR/NA slag-blended cements was performed. The air void system in concrete was evaluated in fresh concrete using AVA and in hardened concrete using an automated image analysis procedure. The mass of scaled material was increased for an increased slag content, in spite of increased compressive strength and flexural strength, decreased water absorption and decreased depth of water penetration of concrete. Increasing slag content resulted in a decrease of the total volume of air in hardened concrete and in a corruption of the air void system exhibited by a decrease of micropores content. The increase of mass of scaled material was proportional to the increase of the spacing factor of air voids, except for CEM III/A cement concrete exhibiting accelerated scaling.