Experimental Studies on the Coupled THMC Processes by COUPLE Equipment - Part I -

Suzuki, Hideaki*; Ito, Akira; Yoshida, Yasushi*; Suyama, Tadahiro*; Kawakami, Susumu; Sasamoto, Hiroshi   ; Yui, Mikazu

The research for numerical experiments on the coupled Thermo -Hydro -Mechanical and Chemical (THMC) processes in the near-field of a high-level radioactive waste repository has been initiated, in order to increase reality in the near-field environmental condition adopted in the evaluation of engineered barrier design and performance assessment.As a part of this research, experimental studies on the coupled THMC processes by COUPLE equipment have been carried out. The COUPLE equipment simulates the coupled processes in the near-field after emplacement of the engineered barrier. The specimen of COUPLE equipment is composed of heater, buffer material and mortar block. In this experiment, temperature at heater and side surface of mortar block was kept at 100 and 70C, respectively. And high-pH water reacted with mortar infiltrates into the buffer material.This report presents the results of measured data by embedded sensor (thermocouple, psychrometer, pressure transducer and pH meter etc.) during the experiment, and direct measurement of pH and water content of buffer material after the experiment.This report also presents the preliminary simulations, of coupled T-H processes, and of chemical process in mortar block and buffer material in the experiment.