Life-cycle cost analysis of RC bridges subjected to multiple hazards

The main structural elements of reinforced concrete (RC) bridges deteriorate with time under such uncertain hazards as scouring and corrosive conditions. In this paper, a multi-hazard framework is proposed to assess the performance of bridges subjected to the main effective uncertain natural hazards during their lifetime. In this assessment, the uncertainties associated with the combined effects of multiple hazards including pier scour, earthquake, carbonation, and corrosion are considered. Therefore, for each of the hazards, their severity relationships have been extracted over time, and the effects of these hazards on concrete elements are presented as resistance dimming parameters. The annual and cumulative losses due to these hazards in unit currency are estimated using the life-cycle costs. For decision making, the present value of the expected cumulative cost associated with the retrofit or design scenarios is evaluated using a cost-benefit analysis. The results for a case study bridge, using the proposed framework, indicate the significant impact of the different scenarios on reducing the expected value of damages or incurred losses due to multiple hazards.