Reinforced concrete bridges: effects due to corrosion and concrete young modulus variation

Resumo

Most of the Brazilian bridges of the federal road network are made of reinforced concrete and are more than 30 years old, with little information about the mechanical properties of their constitutive materials. Along the service life of these bridges many modifications has occurred on vehicles load and geometry and in design standards. Many bridges show signs of concrete and steel deterioration. For this reason it was decided to analyze the stresses in reinforced concrete bridge cross sections to verify the effects due to reinforcement corrosion and variation of the concrete Young modulus on the stress distribution regarding several load patterns and cracking effects in a representative bridge of the Brazilian road network. Different longitudinal reinforcement taxes and two concrete Young modulus – Ec and 0.5Ec – with different percentage of reinforcement corrosion have been used. The analysis considered two finite element models: frame and shell elements as well as solid elements. The results indicate that these variation effects are more significant in reinforcement bars than in concrete.