Análise do desempenho de adesivos epóxi na fixação de barras de aço em reforços estruturais

Abstract

Among the main reinforcement techniques in reinforced concrete structures is the method of embedding reinforcements by means of fixing with resin or polymer mortar. Synthetic resins play an important role in this type of reinforcement because of the performance it offers in its properties. Among them, epoxy resins are the most common ones, however, few studies have been carried out with tests that evaluate their adhesion. In this way, pullout tests were carried out in order to evaluate the pullout strength of three types of adhesives: Sikadur 32, Denverpoxi and Viapóxi. The study consisted in two ways of fixing the hooks, and in the first the steel bars were introduced during the concreting, and in the others, the bonding occurred after a period of 28 days, with the application of the resins, comparing their results. The equipment used did not have enough tension to pull the steel bars anchored, preventing the true difference between the models with and without resin application. Nevertheless, it was verified that the applied tensions proved to be much superior to the constant resistances in the technical manuals of the manufacturers, indicating that the adhesives based on epoxy resin evaluated in this study behave in an efficient way in the bonding of steel bars to the concrete.