2018 Volume 6 Issue 1 Pages 127-146
Recently, numerous instances of severe corrosion damage to the gusset plate connections of steel truss bridges have been widely reported across the world. The corrosion of gusset plate connections has been confirmed to decrease load-carrying capacity, and it can lead to the collapse of the entire bridge. In this study, the remaining load-carrying capacity of a corroded gusset plate connection was evaluated using load testing and finite element method (FEM) analysis. Two different types of gusset plate corrosion were investigated: the corrosion loss of the lower chord flange-to-gusset weld and the corrosion loss of the gusset plate thickness. The loading tests and FEM analyses were conducted on an approximately half-scale model of a real bridge. Corrosion effects were evaluated for an assumed disconnection of 50% of the weld length, and for the loss of 50% and 75% of the gusset plate thickness in a selected region. This study then implemented parametric FEM analyses of the effect of the degree of corrosion on the remaining load-carrying capacity of the gusset plate connection. Finally, based on the results of the parametric FEM analysis in cases with corrosion loss of the gusset plate thickness, a method for evaluating the local buckling strength of the corroded section was proposed.
