Resilience-based seismic risk assessment of aging bridge networks under climate change

Risk assessment of transportation networks exposed to seismic hazard should be based on time-variant probabilistic performance indicators taking into account the aging and deterioration of bridges caused by environmental stressors. In this context, climate change may exacerbate the deterioration rate, harming the capacity of the overall network to sustain the impact of earthquakes without experiencing disproportionate loss of functionality due to excessive traffic flow downtime. This paper presents a probabilistic framework for seismic risk assessment of aging transportation systems based on a quantitative measure of network resilience. The proposed framework integrates the traffic response of the transportation system with the time-variant seismic capacity assessment of reinforced concrete structures exposed to chloride-induced corrosion and prescribed climate change scenarios. The results of the application allow quantifying the detrimental impact of climate change to each single vulnerable facility in the road network and, in turn, on the overall transportation lifeline.