CAREER: Assessment of Infrastructure Risk Under Natural Disasters in a Multiscale Probabilistic Framework

Stanford University, Stanford CA

Investigators

Abstract

The research objective of this Faculty Early Career Development (CAREER) award is to create a new probabilistic description of regional ground shaking during earthquakes, which replaces the near-infinite number of possible disaster scenarios in a region by a small set of representative scenarios. Analysis of infrastructure systems subject to natural disasters is limited by the need to capture complex network effects and difficulties in describing the complex variation of the disaster's impact over a large region. Current infrastructure analyses often estimate disruption given a single scenario disaster. The probability of occurrence of that scenario is rarely incorporated, hindering risk management based on cost-benefit analysis. These limitations are caused by the impossibility of computing disruptions to complex networks under the huge number of possible disaster scenarios that might occur. Multiscale models for ground shaking and transportation network disruption will then be developed to facilitate coarse scale modeling wherever possible, coupled with finer-scale modeling as needed. This multiscale treatment leads to new methods for quantifying the characteristic spatial scale of disasters and infrastructure networks. These analysis techniques will then be applied to other lifeline networks and hazards to more generally understand how characteristic spatial scales relate to infrastructure disruption patterns. Risk-based (performance-based) modeling of individual structures has been a major thrust of structural engineering in the past decade, and multiscale modeling has been a revolutionary approach in computational mechanics. Extension of these concepts to analysis of infrastructure systems will provide new insights into how fine-scale features of infrastructure networks affect performance at the regional scale. Critical lifeline disruption in natural disasters increases suffering and impedes post-disaster recovery, but resources to upgrade these systems are limited and so risk reduction efforts must be carefully targeted. Insights from this research will guide decision making regarding infrastructure development and maintenance. As decision-makers utilize this knowledge, they will ultimately produce safer, more resilient and more economical infrastructure. The project's outreach objectives will facilitate education and training of other researchers (through the production of open-source software and web content), undergraduates (through development of a project-based seminar for prospective engineering majors) and high school students (through continued participation in Stanford's Summer Research Internship Program for High School Students). Assessment of these outreach programs will be achieved by leveraging existing university programs to track the educational/career paths of participants.