DIN II: incorporation of multi-level interdependencies and uncertainties for infrastructure system recovery modeling

Modelling the performance of interdependent infrastructure systems paves the way for strategic infrastructure disaster risk management. The nature of different systems makes it hard to model every system at the same resolution. Modelling different systems at different resolutions can also reduce the computational time for more efficient infrastructure resilience planning, especially when large-scale infrastructure systems are considered. This paper categorises the infrastructure interdependencies into three levels based on the modelling resolution: system-to-system, system-to-facility, and facility-to-facility. The applicability and limitations for each category are identified. The version II of the Dynamic Integrated Network model (DIN II) is introduced to model the infrastructure recovery with incorporating multi-level interdependencies and the uncertainties in the modelling process, which improve the flexibility of the model and increase the accuracy of the modelling results. The DIN II is applied to simulate the performance of interdependent power, water, cellular, transportation and social systems in Galveston City, TX under Hurricane Ike (2008) with considering multi-level interdependencies. Model comparison results imply that the power restoration time will be underestimated if no interdependencies or only facility-to-facility level interdependencies are considered.