Destructive and non-destructive evaluation of reinforced concrete dry casks affected by alkali-silica reactivity damage

Abstract

This article investigates the effect of alkali–silica reaction (ASR) damage on the structural performance of reinforced concrete (RC) dry casks for spent nuclear fuel (SNF) storage. Dry casks have an initial licensed lifetime of 20 or 40 years with the possibility of an extension of another 40 years. Due to lack of a permanent storage facility in the United States, an extension of the service life of dry casks that are currently in use and that were designed for shorter service lives is a critical step. Deterioration of concrete due to ASR is a major concern as has been reported for some nuclear facilities. In this study, the effect of ASR aging on the tip-over response of a vertical RC cask is experimentally studied for the first time using 1/3-scale physical models. An accelerated aging method was used to represent the long-term degradation of the structure. A series of non-destructive tests were performed to monitor the aging progress. At the end of the aging period, the structural performance of the casks is evaluated experimentally under tip-over impact. The results are compared with data obtained from a tip-over test on an undamaged cask. In addition, a detailed finite element model of the cask is developed to simulate the tip-over impact in aged conditions.

Keywords:

• Reinforced concrete
• alkali–silica reaction
• dry casks
• nuclear fuel storage
• non-destructive testing
• finite element modeling

Acknowledgments

The findings presented herein are those of the authors and do not necessarily reflect the views of the sponsor. The authors are thankful to Dr. Arezou Attar for her help with the preparation of the physical models of the casks and for taking non-destructive measurements.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This financial support for this project was provided by the United States Department of Energy through the Nuclear Energy University Program under the Contract No. 00128931.