RC BRIDGE FATIGUE RELIABILITY AND BRAZILIAN STRUCTURAL DESIGN ADEQUACY ASSESSMENT

Resumo

The fatigue ultimate limit state is one of the most important considerations in the bridges’
design. Sections’ geometric characteristics, material properties and traffic are influential factors
subjected to different levels of uncertainty. Hence, it is interesting to investigate the impact of their
variabilities in the fatigue reliability of the reinforcements, here defined for four isostatic reinforced
concrete (RC) bridges with two girders, through Monte Carlo simulations (MCS). It is also analyzed
how adequate is the typical design approach. The results show that the extrapolated traffic has greater
potential to penalize the reinforcements’ fatigue performance than the Brazilian standard design vehicle
TB-450. The importance of a more accurate technical control in the execution of bridges is highlighted,
since the geometrical and material variabilities also contribute to the penalizations.