Study on the simplified evaluation method of the remaining load-carrying capacity of a corroded steel I-girder end using FEA

In a steel I-bridge, corrosion often occurs severely at the I-girder end rather than at other parts. Therefore, this work mainly discusses the corrosion at the I-girder end as a bearing problem and shear capacity of the end plate. A finite element model (FEM) of a corroded steel I-girder end is developed considering commonly occurring corrosion at first. For the initial imperfection of a steel I-girder end, the initial deformation and residual stress are considered in the model which are simulated by elastic buckling analysis (eigenvalue analysis) and thermal stress, respectively. To investigate the effect of the corrosion pattern on the strength development, the single-area corrosion (flange, stiffener, web) and multi-area corrosion are included in the case study. Finally, the simulation results from the case study using finite element analysis (FEA) are used to formulate the simplified equations for evaluating the remaining load-carrying capacity of a corroded steel I-girder end with the specified corrosion patterns. Furthermore, for the engineering design and preliminary assessment of a corroded steel I-girder end, the simplified equations for evaluating the remaining yield strength ratio are also provided based on the remaining load-carrying capacity. •FE analyses for investigating the load-carrying capacity of the corroded I-girder end are conducted.•Equations for determining the load-carrying capacity of the corroded I-girder end are proposed.•Equations for determining the remaining yield strength of the corroded I-girder end are proposed.