Analytical demonstrations to assess residual bearing capacities of steel plate girder ends with stiffeners damaged by corrosion

Many field surveys depict that steel plate girder ends tend to corrode due to the leakage of water from construction joints and/or detention of rain water near bearing regions. In many cases, buckling failures of plate girders were observed due to the excessive loss of material at the bottom portion of bearing stiffeners. In this study, the effect on the buckling strength of steel plate girder due to the corrosion damage at bearing stiffeners was investigated. Full-scale experimental tests were performed on two plate girder ends to determine the bearing capacity. Bearing capacity and failure modes were also verified by numerical analyses. Initial imperfections and welding residual stresses were also taken into account in analytical models. The simulation of the model was extended to the various corrosion damages, considering different damaged heights and thicknesses of the bearing stiffener near weld seam. All results were plotted in terms of remaining bearing capacity versus damage thickness ratio keeping the damage height of the stiffener constant. In this study, a damage parameter Reduced Thickness Ratio was used to assess the ultimate capacity and buckling of steel plate girder end with various corrosion levels.