Potencialidade da detecção de corrosão das armaduras em corpos de prova de concreto armado utilizando termografia e indução eletromagnética

Abstract

The study of structures and pathological manifestations in a minimally invasive way is increasing in the construction industry. These studies aim to mensure the surface hardness of structures, the resistivity of concrete, among other. In order to detect possible pathology in the steel present in reinforced structures, a non-destructive test (NDT) using a thermal camera will analyze the position of carbon steel structure inside a small idealized reinforced concrete specimens molded in loco. Through a thermal stress, generated by a induction electromagnetic equipment, power will be supplied to the metal rebar, which by conduction, will transfer heat to the concrete specimens surface from inside. After 22, 23, 19 e 31 seconds, it was possible to detect the steel bar inside the specimens made with brazilian cement called Cimento Portland II, Cimento Portland IV, Cimento Portland V (ARI) e Cimento Portland B (BRANCO), respectively. The induction heating was apply during 150 seconds in each specimen and was recorded a termal variation about 5ºC on surface where the metallic elements were positioned. After the test of the specimens molded with various types of cement, one of the binders was selected and another 20 specimens were molded. These new specimens were subjected to an accelerated induced corrosion test and inspected using active thermography. Reinforcement corrosion were successfully detected in the thermograms and the induced armor corrosion test had similar results to other papers.