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Extreme Events and the Sustainability of Civil Infrastructure Systems

The impact of extreme events is in reality the interaction among three systems; the natural environment, the human community, and the built environment the infrastructure that supports human activities. The sustainability of our infrastructure depends upon knowledge of the natural environment – for example, the research on global warming and its impact on meteorological events such as storms, droughts and floods. Sustainability also depends upon the demographic composition and distribution of population. Shifts in population require expanded infrastructures; people moving into hazardous regions like coastal areas may require new infrastructure. The events of September 11, 2001 show once again the vulnerability of our civil infrastructure systems. However, the on-going attention may provide the opportunity to increase the sustainability of civil infrastructures while reducing their vulnerabilitythe focus of this paper. The paper first presents background related to sustainability and vulnerability of infrastructure systems. A systematic procedure including an optimization algorithm is presented to incorporate sustainability concerns into the vulnerability analysis. An illustrative example is given, followed by concluding remarks on its integration with past research on vulnerability of civil infrastructure systems.