Enhancing Seismic Safety of Nuclear Facilities

Sources: David McCallen and Dan Hawkes

Last month (May 2015), the U.S. Department of Energy (DOE) announced a collaboration involving Berkeley Lab, U.C. Davis, and the University of Nevada, Reno, on a major DOE-supported multi-year project to develop advanced computational tools for modeling and simulating the earthquake response of nuclear facilities, including the effects of soil-structure-interaction.

This project, led by UCOP/ESD’s David McCallen, is focused on the development of a modern, high performance, nonlinear-time-domain computational framework that will enable enhanced understanding of the expected levels of damage, and margins against failure, for critical facilities subjected to earthquake ground motions. The project will take advantage of DOE’s leadership capabilities in high performance computing, and will leverage computational geomechanics capabilities at the U.C. Davis and earthquake shake table experimental testing capabilities at the University of Nevada, Reno.

 

Postprocessing of an NPP that is analyzed using realistic 3D (6D) seismic wave field (upper left half) and the same one analyzed using 1D wave (lower right half). Click on image to play movie.

This effort will integrate advanced simulations, together with unique experimental data, to develop enhanced understanding of earthquake response phenomena. It will provide a modern computational tool for performing risk-informed, performance-based design of critical facilities. Ultimately this effort will develop a more accurate and realistic understanding of earthquake soil-structure-interaction phenomena, and provide for better quantification of the safety margins against earthquake-induced failure of critical facilities.

DOE has had a long-term commitment and leadership role in establishing guidelines and analysis capabilities for the seismic safety of critical facilities. In the late 1980s, the DOE developed the first risk-informed, performance-based design standards for nuclear facilities (DOE Standard 1020), which provided the foundation for a number of national standards for nuclear facility earthquake safety.

Key members of the project team in addition to McCallen include Boris Jeremic (U.C. Davis and Berkeley Lab), who will serve as PI for code development, and Ian Buckle (University of Nevada, Reno), who will serve as PI for scaled experiments on soil-structure interaction. The project will draw on Lab personnel and resources from the Earth and Environmental Sciences Area (formerly Earth Sciences Division), Computational Sciences Area, and NERSC.