Strategic assessment of bridge susceptibility to scour

Abstract

Scour-induced failures of bridges pose a global challenge, leading to significant economic and service losses. Compounded by infrequent inspections and inadequate consideration of hydro-geological factors in current scour risk assessments, this issue is particularly pressing in the context of climate change and associated hazards. Addressing the imperative for enhanced infrastructure resilience, this study introduces a framework for scour risk management. Utilizing Geographic Information Systems (GIS) datasets and applying the Analytic Hierarchy Process (AHP) to assess various weighted factors affecting scour risk, we have systematically mapped information layers encompassing structural, riverine, geological, and flood risk to conduct a strategic scour susceptibility assessment. The proposed approach is applied to the railway network in southeast England, identifying scour-susceptible bridges that can be prioritized for detailed inspections. Compared to the existing scores, the proposed scour risk scores for approximately 30 railway bridges in the region were adjusted, with 22 transitioning from medium to high priority. Our proposed methodology, exemplified by this case study, offers asset managers deeper insights into the determinants of scour susceptibility of bridges and facilitates informed decision-making for prioritizing scour-mitigation measures across the network.