Corrosion damage evaluation of loaded steel strand based on self-magnetic flux leakage

As for the corrosion damage quantification of steel strands by self-magnetic flux leakage (SMFL), the influence of load on cable-stayed bridges was seldomly studied. In this paper, an experimental study was conducted to analyze the loading impact of the damage quantification-based SMFL signal. A characteristic index C was proposed to evaluate the corrosion degree accurately. The experimental results show that the variation of the SMFL signal caused by the corrosion under the load condition is analogous to the unstressed strand under different measuring distances, corrosion widths, and corrosion degrees. The effect of corrosion damage still dominates the signal distribution of SMFL, but increasing load magnifies the SMFL signal's magnitude. The proposed characteristic index C can quantitatively characterize the corrosion damage of steel strands under different loading magnitudes and corrosion widths conditions. When the corrosion degree is less than 30.89%, the corrosion degree of tensile steel strands could be quantified by the proposed index C.