Pitting Corrosion Propagation Analysis of Reinforcement in RC Bridge Beams Considering Uncertain Information

Abstract

The prediction of pitting corrosion-induced structural performance degradation is limited by the inspection means and experimental data. Incomplete information and tempral and spatial uncertainties of corrosion are integrated to develop the time-dependent pit depth model. The reinforcement corrosion is divided into two stages in this model. The approach is illustrated by a removed concrete bridge. The evolutionary characteristic of probability density function of the pit depth is analyzed, and the probabilistic distribution pattern and distribution parameters are also obtained. Besides, The sensitivity of input parameters on the pitting model are also discussed. The results show that under appropriate conditions of concrete strength (>25MPa), increase the same percentage of concrete strength is more sensitive to the pit depth than improvement the same percentage of concrete cover thickness. The effects of continuous improvement of concrete strength or increase the thickness on corrosion depth gradually decreases. The proposed procedure can be used to evaluation of existing reinforced concrete bridge.