Adapting Bridges to Climate Change: Impacts, Regulatory Responses, Case Study, and Challenges

Abstract

Climate change increasingly exposes critical infrastructure systems, like bridges, to hazards for which these systems were neither originally designed nor adequately maintained. Over the past decade, both researchers and stakeholders have produced a growing body of scientific studies and practice-oriented guidelines aimed at enhancing infrastructure resilience, but there is still a lack of studies focused on bridges. This paper applies an integrated assessment approach, combining local monitoring data, biascorrected regional climate projections, physics-based finite element modelling, and reliability analysis, to evaluate the structural implications of future temperature scenarios. After reviewing projected climate impacts and current regulatory responses, with particular emphasis on the evolution of the Eurocodes, the methodology is applied to an existing prestressed concrete bridge in Portugal. Temperature projections derived from regional climate models are downscaled to the bridge site and incorporated into a probabilistic structural assessment. Results indicate that, under a high-emission scenario, projected temperature increases may lead to reductions in reliability index and increases in expansion joint displacements for a long-term period. The comparison between the first and second generations of Eurocodes highlights the transition from historically calibrated thermal actions to climate-adjusted design values. This study demonstrates that climate change represents a quantifiable structural action for bridges and underscores the need for reliability-based, forward-looking design and lifecycle management approaches.