Swelling Behavior of Bentonite-Based Backfilling Materials in Nuclear Waste Repository Conditions

Abstract

During the postconstruction phase, the stress equilibrium conditions within the proposed underground nuclear waste repositories may alter because of various factors, such as far-field mining activity, fluctuation of the groundwater table, and seepage erosion. A reduction in the transmitted stress from the host rock may destabilize the isochoric condition, leading to swelling displacement of backfilling and buffer materials. In the current study, the swelling behavior of bentonite-based backfilling materials was studied. Laboratory tests were carried out on compacted bentonite (