Fragility Development

Task Description - As a culmination of all of the research programs within the OpenSRA effort, the research programs developed fragility curves for individual natural gas infrastructure components to help inform utility owners and regulators of the overall seismic risk of their systems. Within the individual research tasks, each was responsible for a piece of infrastructure; Liquefaction and Landsliding focused on buried pipeline, the Fault Displacement team informed both the buried pipeline fragility, as well as the well and caprock fragilities; the Surficial Infrastructure focused on tanks, well trees, and other subsystems and components of storage facilities; and the Wells and Caprocks team focused on wells (below ground) and storage caprocks. Each team performed sensitivity studies to assess the input parameters, to see which changed the final answer the most. The parameters deemed “most sensitive” were then used to develop the final fragility model. Using the PEER Risk framework, each team developed a fragility curve for their infrastructure that took the intensity measure (i.e., PGA) to the risk of a specific damage measure (DM, i.e., pipe rupture). These fragility curves have been implemented into OpenSRA and will be used to calculate the risk of DM’s for each piece of infrastructure.

Lead Investigator: Jennie Watson-Lamprey (Slate Geotechnical Consultants)

Team Members: Norm Abrahamson (University of California, Berkeley), Jonathan Bray (University of California, Berkeley), Micaela Largent (Slate Geotechnical Consultants), Chris Bain (University of California, Berkeley), Daniel Hutabarat (University of California, Berkeley), Elide Pantoli (University of California, San Diego)