Experimental assessment of the fatigue strength of corroded bridge wires using non-contact mapping techniques

Highlights: • Surface roughness of corroded wires, subjected to an accelerated corrosion method, was measured using a 3D laser scanner. • Spatial characteristics of area loss and pit depth were quantified on nominally identical corroded specimens. • Different corrosion indicators were specified in order to explore correlations with fatigue performance. • The maximum area loss was better correlated, compared to maximum pit depth, with the breakage position. • Effect of corrosion was quantified through the estimation of the coefficients in the S-N relationships. This study investigates the fatigue performance of corroded bridge wires by providing characterisation of the corrosion effects through non-contact surface mapping and by undertaking fatigue tests under constant amplitude loading. For the corrosion level investigated, the breakage position in corroded wires was found to be better correlated with maximum area loss rather than pit depth. Using also test results for un-corroded wires, S-N relationships were determined for both that set and the corroded wire set created in this study. The effect of corrosion was quantified through the estimation of the coefficients for both the mean and the design S-N curves.