Time-Dependent Resilience in the Presence of Interacting Multiple Hazards in a Changing Climate

Abstract

The safety and serviceability of in-service structures and infrastructure systems are often threatened by natural hazards. Asset owners/decision makers are thus concerned about the resilience of an object of interest (structure or infrastructure), that is, its ability to be in readiness for, to absorb, recover from, and adapt to disruptive events. This is particularly the case when considering the potential impacts of climate change, which may lead to nonstationary natural hazards in the future (e.g., increasing wind hazard in a changing climate). Moreover, in many occasions, the presence of concurrent multiple hazards may result in more severe performance reduction to structures/infrastructures, compared with the occurrence of single hazards. This paper proposes an innovative method for the time-dependent resilience assessment of structures and infrastructure systems exposed to the impacts of concurrent multiple hazards in a changing climate. The interaction between different types of hazards is reflected through the mutual dependency between the performance functions associated with these hazards. New insights into the time-dependent resilience problem are also provided through a new concept of the performance concern index (PCI). It is shown that the mean nonresilience (i.e., 1 minus the mean value of resilience), if small enough, can be approximated by the mean value of the average PCI over the time domain of interest. Two examples are presented to demonstrate the applicability of the proposed method, and to investigate the sensitivity of resilience to key factors such as the interaction between multiple hazards and the climate change scenario.