Modelagem computacional de vigas de concreto armado sujeitas à corrosão

Abstract

This work aims to assess by the finite element method the corrosion effect in reinforced concrete beams under flexure, considering the reduction of the tensile strength, the elastic modulus and the cross-sectional area of longitudinal reinforcement. So, a beam 5000 mm long, 500 mm high and 169 mm depth was modeled in DIANA ® version 10.3 considering corrosion rates of 10%, 20% and 30%. Concrete was modeled with compressive strength of 53 MPa while the steel was modeled with yielding stress of 500 MPa and elastic modulus of 210 MPa, both reduced according to empiric model by Ou et al (2016). Cross-sectional area of longitudinal reinforcement, composed by 16 mm diameter bars was reduced according to model by Lu et al (2016). Results showed discrete differences in displacements and increasing of the severity of damage caused by cracks according to increasing on the corrosion rates, with crack openings higher than those allowed by the normative limits to respect the service limit state. Results also showed that coupling of the three corrosion effects on the steel reinforcements make difficult keeping the cross-sectional area for mobilizing of the tensile strength, reduce the beam resistance and increase its deformability.