Metrics for Bridge Resilience Indicators

Numerous past events have shown that natural and anthropogenic hazards have the potential to cause significant societal losses through damages to infrastructure systems and associated disruptions of societal functionalities. Examples hereof count the hurricanes Katrina and Rita in the USA, the attack on the Old Mostar bridge in Bosnia and Herzegovina during the Balkan war and the failure of the Morandi bridge in Italy. The degree to which such events impose consequences and impair or reduce societal service provisions is commonly assessed through the concept of resilience. Societal resilience may be significantly supported by safe, sustainable, and resilient infrastructure systems. Several studies have been undertaken by researchers with regards to the concept of resilience management to enhance decisions on the infrastructural systems. An indicator-based framework has been presented in reference (Turksezer, Limongelli, and Faber 2020) to provide a tool to assist the decision maker in service life management of infrastructure resilience. In principle, using this framework, the decision maker may estimate the resilience of the system through observable characteristics (resilience indicators) and assess the efficiency of different design or intervention measures. This paper aims to propose a number of metrics for the resilience indicators that can facilitate the practical implementation of the framework.