Probabilistic Analysis of Chloride Ingress Repair Costs Considering External Forces and Vulnerable Sections of RC Girders

Abstract This study analyzed the chloride ingress repair costs for RC girders by considering cold joints and external force conditions. The diffusion behavior of chloride ions, which varies with the stress conditions, was quantified. A two-span RC continuous girder was assumed to evaluate the magnitude of stress in each section under cracking load, and these results were comprehensively considered along with the quantification of chloride ion diffusion behavior. Then, the change in chloride ion diffusion behavior owing to external forces on the RC girders was analyzed to evaluate the service life under chloride ingress. At the locations with cold joints, the service life decreased by up to 33.9% owing to the higher baseline diffusion coefficient in the cold joint areas than that in sound concrete and significant increase in the diffusion coefficient with increased stress. Furthermore, this study analyzed the chloride ingress repair costs required to achieve the target service life of the RC structure with consideration of the external forces and cold joints using deterministic and probabilistic analyses methods. Probabilistic analysis offers the advantage of deriving the repair frequency and cost results in the form of continuous functions. Considering the four main points of the structure under analysis, the maintenance costs were evaluated at 2777.6 $/m 2 in the deterministic analysis and 2337.6$/m 2 in the probabilistic analysis. A repair cost analysis flowchart that integrates various repair processes can facilitate the analysis of repair processes that have a dominant influence on the overall maintenance cost estimation of RC girders.