Dependence of Residual Axial Force on Thickness and Shape in Corroded High-Strength Bolts

AbstractThis paper presents the results of an investigation of the decrease in residual axial force in corroded high-strength bolts in friction joints for steel bridge girders. The results of a finite-element analysis revealed that the root-mean-squared value of the thickness reduction near the washer was a useful parameter for evaluating the residual axial force for the corroded bolts. Furthermore, the effect of the corroded bolt’s shape on the residual axial force could be evaluated based on the thickness reduction near the washer. To verify the validity of this approach, measurements were carried out on corroded bolts cut from a steel bridge girder. The results indicated that the proposed method can estimate the residual axial force to an accuracy of ±15%.