Structural Analysis for Seismic Design Standards
DOE nuclear processing facilities at the Savannah River Site were designed before there were provisions for seismic resistance design in structural codes. Therefore, the structures do not satisfy the reinforcement detailing and ductility requirements of current seismic design standards. The Office of Nuclear and Facility Safety of the Office of Environment, Safety and Health (EH) formed a team of specialists to evaluate the design and seismic response of these facilities.
CTLGroup experts were asked to perform the structural analysis part of the investigation. Their expertise was needed since the analysis went beyond conventional techniques to model non-linear behavior of the buildings and the joints. The team not only evaluated previous design and analyses on the buildings, but also conducted physical inspections, obtained concrete core samples, obtained petrographic analyses, and created finite element models to conduct structural analyses. The structural analyses were to determine the performance of these facilities if subjected to ground motion records developed in accordance with DOE Natural Phenomena Hazards Standards.
The analyses concluded that, for the ground motion records developed according to the DOE Standards, collapse of the buildings under consideration is unlikely and, in most cases, the buildings will remain undamaged. The roof displacements under various seismic margin earthquakes were in the favorable range, and the probability of failure from a seismic event was found to be less than 2 x 10-4, which satisfies DOE Natural Phenomena Hazards criteria.