A probabilistic approach to assessing AGR core life

The authors provide an overview of the early stages of a new approach for assessing the integrity of AGR graphite cores which incorporates improved methods and accommodates the presence of broken reactor components using a probabilistic treatment. Nuclear Electric has been developing this methodology based upon the probabilistic analysis of core ageing and component failure with a computer code CORSET. The code examines the distortion of the core under various operating conditions, allowing for local discontinuities due to component failure. These distortions are repeatedly assessed allowing for statistical variations in component dimensions and properties, thus constructing a probabilistic distribution against which the required operational and safety features can be confirmed