Epoxy-coated Bars for Concrete Construction

Abstract

Epoxy-coated bars have been developed to prevent the deterioration of concrete structures due to reinforcement corrosion. The properties of corrosion resistance, bendability without serious damages of coating, bond strength to concrete, resistivity to percussion and abrasion are required for the bars. To examine the bars, exposure test in marine environments, bend test, pull-out from concrete and trial execution were carried out.
(1)Epoxy-coated bars did not corrode in crack-induced concrete specimens which were exposed in marineenvironments for 3 years. (2) Epoxy-coated bars could be bent 180° with the radius of twice the diameter of the bars under the ordinary conditions of execution. (3) The reduction of the bond strength of epoxycoated bars to concrete required 20% increase of lap joint lengths. (4) The bars embeded in concrete beams which were subjected repeated bending stress up to 38 kgf/mm2 showed no degradation of coatings. (5) Cares for coating protection did not reduce the work efficiency of bending and construction of the bars in execution yard.