Experiment and modelling of performance degradation of boric acid-corroded concrete in nuclear power plants

ABSTRACT Borated water leaks out of spent fuel pools from time to time and degrades the performance of concrete support structures. Therefore, a comprehensive experiment is essential for exploring the degradation characteristics of concrete located in a boric acid environment. The purpose of this paper is to investigate the leaching depth, elastic modulus, and cube compressive strength of concrete immersed in boric acid solutions through experiment. The effects of immersion time, boric acid concentration, temperature, and water/binder ratio on the leaching depth, elastic modulus, and cube compressive strength of concrete are evaluated in a quantitative manner. Based on the experimental results, three models for the leaching depth, elastic modulus, and cube compressive strength of concrete are derived. One of the advantages of these models is that once the elastic modulus and cube compressive strength of sound concrete and the leaching depth are measured, the elastic modulus and cube compressive strength of boric acid-affected concrete can be evaluated. Finally, the validity of the three models is verified with experimental results.