ESTUDO EXPERIMENTAL PARA DETERMINAÇÃO DA CURVA DE WÖHLER EM BARRAS DE AÇO CA-60 DE 7 MM

Abstract

In reinforced concrete structures subjected to mobile loads, checking the effect of fatigue is of paramount importance to ensure safety during its useful life. The absence of a standard that could prescribe the behavior of steel bars and welded mesh of CA-60 steel subjected to these loads was the main motivation for this study. With the use of pre-molded structures with welded mesh, especially in bridge slabs, the investigation of the influence of the welding process on fatigue resistance is of paramount importance for dimensioning. This work developed a comparative experimental study between insulated bars and welded mesh of CA-60 steel rebar, with a diameter of 7 mm, in relation to fatigue behavior, presenting the Wöhler’s Curves, relating three levels of tension fluctuation and the number of rupture cycles. The results of the study showed how much the welded mesh can be less resistant than the bars that did not undergo a welding process. Thus, this work provides a contribution to the improvement of normative provisions in relation to the design and verification of fatigue in reinforced concrete elements.