Dynamic time-dependent vulnerability of infrastructure: critical review and modelling framework proposal for NaTech risk assessment

Infrastructure vulnerability is crucial to predict the consequences after a NaTech event. This metric is subjected to temporal evolution due to numerous factors, e.g. multi-hazards, ageing, maintenance, fatigue. The consideration of these dynamic effects is often overlooked. The present paper proposes a concise literature review and a framework being able to include, account for time-dependent, parametrized vulnerability/fragility curves. Therefore, we show the importance of these dynamic effects across short- and long-term horizons and compare the risk assessment with a static case. Two simple examples are given and demonstrate significant differences. Precautions should be taken due to intrinsic uncertainties and necessary working assumptions.

Keywords: NaTech risks, civil engineering, damage potential, multi-hazard vulnerability, time-dependent modelling.