Groundwater recovery experiment in Mizunami Underground Research Laboratory; Numerical simulation of H-M coupled behavior of rock and backfill materials to evaluate the influence on the surrounding rock

Takayama, Yusuke  ; Sato, Toshinori  ; Onoe, Hironori ; Iwatsuki, Teruki  ; Saegusa, Hiromitsu; Onuki, Kenji

In the Mizunami Underground Research Laboratory, groundwater recovery experiment is being conducted to construct the method to understand the transition of geological environment due to groundwater recovery at the -500m access and research gallery-north. As a part of this experiment, backfill test is planned using drilling pits filled with artificial materials (clay and concrete) to evaluate the influence on the surrounding rock mass due to the interaction of rock and artificial materials. In this study, numerical simulation of the backfill test has been carried out to predict the qualitative hydro-mechanical behavior.