2017 Volume 71 Issue 1 Pages 161-168
An artificial barrier with cementitious material in a radioactive waste disposal facility will be affected for a long term by high temperature loading due to radioactive heat emission. In this study, some basic experiments were conducted to evaluate the long-term thermal loading effects on hardened mortar properties using sole OPC and OPC partially including fly ash（as called FAC）. In the result, FAC revealed that whereas the continuous pore volume much decreased shortly after high temperature exposure, it increased with time passing under the same condition. The similar tendency was observed under sealing condition at high temperature as well. These findings suggest the possibility that C-S-H structures have changed due to not only drying bound water but also successive thermal loading itself.
