ABSTRACT
This study deals with multi-hazard risk assessment of a spatially distributed civil infrastructure system with interdependent constituents. A regional system – consisting of six bridges, two roadway stretches and a levee – is selected and analyzed. During the analysis of this dynamic and relatively complex system, the following hazards are considered: (i) flood hazard due to extreme rainstorms which can cause internal erosion of the levee and (ii) seismic hazard and its triggering effects which can cause structural damage to the bridges and levee, and liquefaction-induced damage to the roadway stretches. The risk assessment of the system is conducted through a probabilistic event-based analysis. The results of this analysis are presented in terms of risk metrics commonly used in the field of financial engineering for portfolio optimization. An optimum risk mitigation strategy is also discussed.
