A Methodology Supporting the Risk-Informed Management of Materials Degradation

摘要

Meeting projected energy needs while managing carbon emissions in the United States will demand extension of nuclear power plant operating licenses beyond 60 years. However, the methodological bases for the risk-informed management of materials degradation in aging reactors are limited. Under the auspices of the U.S. Nuclear Regulatory Commission's Proactive Materials Degradation Assessment (PMDA) program [1] a growing resource of materials degradation data is being generated. These data, which address the susceptibilities of numerous classes of passive components to various materials degradation mechanisms, are not explicitly risk-oriented. In this paper, we describe a methodology that allows PMDA data resources to be recast in a form compatible with probabilistic risk assessment (PRA) models, thus permitting the risk significance of a broad range of materials degradation phenomena to be assessed, and reactor aging management strategies to be more risk informed.