COUPLED THERMAL HYDRAULIC AND MECHANICAL ANALYSES TO EVALUATE SWELLING CHARACTERISTICS

Abstract

Buffer material as an engineered barrier system for high-level radioactive waste disposal is expected to seal initial cracks or gaps within it during re-saturation process. Since the self-sealing ability is based on swelling behavior of the buffer material, estimation of swelling characteristics during re-saturation process is very important. In this paper, the theoretical model for evaluating swelling characteristics of saturated buffer material is expanded to unsaturated media, and is applied to coupled thermal, hydraulic and mechanical model. After the verification by using a series of swelling experiments, it is applied to the heating test conducted at Kamaishi mine and its applicavility is examined.