Risk-based bridge life cycle cost and environmental impact assessment considering climate change effects

To enhance sustainability and resilience against climate change in infrastructure, a quantitative evaluation of both environmental impact and cost is important within a life cycle framework. Climate change effects can lead performance deterioration in bridge components during their operational phase, highlighting the necessity for a risk-based evaluation process aligned with maintenance strategies. This study employs a two-phase life cycle assessments (LCA) framework. First, risk assessments are conducted to evaluate the impact of climate change on steel plate girder bridges and prestressed concrete (PSC) girder bridges under identical structural conditions. The reduction in flexural strength of steel plate girders and PSC girders due to changes in environmental variables such as temperature and relative humidity, induced by various climate change scenarios, was evaluated analytically. Subsequently, life cycle environmental impact and cost assessments were performed, including maintenance outcomes derived from risk assessments. The findings revealed that the environmental impact and cost could increase by approximately 12.4% when climate change is considered, compared to scenarios where it is not taken into account. Sensitivity analyses were performed to identify the key factors influencing environmental impact and cost. The analysis determined that the frequency of preventive maintenance, the recycling rate, and environmental cost coefficient weight in the life cycle assessment significantly affected the results.