Study on methods to prevent piping and erosion in buffer materials intended for a vertical disposal pit, at Horonobe URL

Jo, Mayumi*; Iwatani, Takafumi*; Kawakubo, Masahiro*; Ishii, Tomoko*; Ono, Makoto*; Nakayama, Masashi 

For the purpose of "maintaining the soundness of the artificial barrier", we are studying "restraints on the outflow of the buffer material". We conducted an experiment of a scale of 30 cm to 1 m in an actual underground environment and confirmed the occurrence of the buffer material outflow under water inflow conditions. The experiment in this study was undertaken in order to acquire the necessary data for considering a method to control the outflow of the buffer material.