PROBABILISTIC RESILIENCE ASSESSMENT OF CRITICAL INFRASTRUCTURE SYSTEMS UNDER BLAST RISK

To quantify risk, protective design practitioners have considered several sources of vulnerability, for either structural or nonstructural elements, while assessing critical infrastructure systems (CIS). This chapter proposes overcoming some of the limitations noted in the current practice of risk assessment of blast-loaded CIS by integrating postblast functionality loss and downtime within a unified PRA framework. To facilitate the integration of resilience concepts within the broader PRA framework, relevant definitions are reviewed. A broad overview is given of some approaches that can be applied in an in-depth assessment of critical infrastructure threatened by blast events of malicious origin. The nontrivial variability documented in key wavefront metrics, further compounded by the extreme uncertainty associated with the defining variables of a blast scenario (e.g., charge mass) clearly demonstrate the necessity of a sound probabilistic approach.