DURABILITY OF HARDENED MORTAR UNDER HIGH-VACUUM CONDITION

摘要

Cementitious materials are expected to be the construction materials for lunar base construction. And, the possibility of utilization of cementitious material for lunar construction will increase more in future. However, the durability of cementitious materials in the lunar environment still has many unknown problems. In this study, the mechanical properties of mortar in the high-vacuum (10~(-3) to 10~(-5)torr) were evaluated for the future lunar base construction. From the results, it was found that the mechanical properties of mortar exposed to the high-vacuum during 3 months did not show any significant deterioration. In the high-vacuum environment, however, it was found that the mortar showed a greater water evaporation and a significant change at early stage of vacuum exposure. In addition, the strength showed a considerable change at the early stage at the beginning of exposure. And then after this stage, it was found that the strength still shows some increase. This implies that the high-vacuum environment does not have detrimental effect on the development of strength of the cementitious materials.