Load-Carrying Capacity of Corroded Gusset Plate Connection and Its Repair Using CFRP Sheets

Abstract

Recently, several events involving the corrosion-induced damage of gusset plate connections of steel truss bridges have been reported worldwide. In this study, the remaining load-carrying capacity of a corroded gusset plate connection was evaluated through loading tests and finite element method (FEM) analyses using a model approximately 50% of the size of an actual gusset plate connection. Two potential forms of corrosion, that is, weld and cross-sectional corrosion, on the gusset plate were considered in order to investigate the reduction in the load-carrying capacity. Then, parametric FEM analyses were conducted to determine the effect of the corrosion level on the remaining load-carrying capacity of a specimen model and a full-scale model of an actual connection. The loading tests and parametric FEM analyses indicated that with increases in the dimensions of the corroded sections, the load-carrying capacity of the gusset plate connections exhibited nearly similar linear decreases. Furthermore, the effectiveness of a repair method for the corroded gusset plate connection using carbon fiber–reinforced plastic (CFRP) sheets was investigated. The loading tests were conducted considering the area, direction, and location of the bonded CFRP sheets. As a result, this study proposed an appropriate repair method using CFRP sheets that could help recover the load-carrying capacity and improve the deformation performance of corroded gusset plate connections.