Old and New Coatings Against Chloride Ingress in Concrete

Abstract

The results of laboratory and in situ tests of a number of different types of coatings commercially available in Croatia (polymer-cement, epoxy, acrylic, epoxy-acrylic and epoxy-polyurethane), used for reinforced concrete protection of the KRK bridge, are presented. The tests have been carried out throughout the last ten years. Some coatings like epoxy and polymer-cement were found completely unacceptable for technical reasons. However, epoxy-polyurethane coatings applied on the concrete finished with a thin layer of epoxy-cement mortar are estimated rather effective. They had high adhesion strength (above 2.0 MPa), very low gas permeability, low capillary absorption, satisfactory water vapor diffusion and satisfactory aging resistance.