AGING PROCESSES IN NUCLEAR REACTORS

AS NUCLEAR PLANTS GROW OLDER, ENVIRONMENTAL CONDITIONS MAY AFFECT THE PERFORMANCE OF PLANT CONCRETE AND STEEL STRUCTURES. WE PROPOSE TO DEVELOP A STRATEGY WHICH CAN BE APPLIED TO CONCRETE STRUCTURES. IT WILL BE DIRECTED TOWARDSTHE DEVELOPMENT OF METHODS TO ANALYZE AND UNDERSTAND AGING EFFECTS, INCLUDING THE COMBINED EFFECTS OF TIME, TEMPERATURE, RADIATION, HUMIDITY, STRESS, CHEMICAL ENVIRONMENT AND ELECTRICAL AND MAGNETIC FIELDS. IT WILL INCLUDE CONSIDERATION OF CURRENT METHODS AND TECHNOLOGY FOR SURVEILLANCE AND MAINTENANCE OF CONCRETE STRUCTURES. IN ADDITION, METHODS FOR POST-SERVICE EXAMINATION AND TESTING WILL BE PROPOSED. FINALLY, AGING ASSESSMENT METHODS WILL BEDEVELOPED FOR CONCRETE STRUCTURES. THE STRATEGY WILL BE APPLIED TO A SINGLE CONCRETE COMPONENT OF A NUCLEAR PLANT IN PHASE I. IN THE SECOND PHASE, EACH OF THE CONCRETE AGING PROCESSES WILL BE EXAMINED IN GREATER DETAIL. PLANT COMPONENTS IN DIFFERENT TYPES OF CONTAINMENTS WILL BE EXAMINED TO DETERMINE WHERE FAILURES ARE MOST LIKELY TO OCCUR AND WHERE THEY ARE MOST SIGNIFICANT IN TERMS OF REACTOR SAFETY.