Abstract
The pit filler material of the underground cavern-type radioactive waste disposal facility, which is poured directly around the radioactive waste packages where high temperature environment is assumed by their decay heat, is concerned to be adversely affected on the filling behavior and its hardened properties. There also are specific issues that required quality of construction must be achieved by unmanned construction with remote operation, because the pit filler construction shall be done under radiation environment.
In this paper, the mix proportion of filler material is deliberated with filling experiments simulating high temperature environment, and also the effect of temperature on hardened properties are confirmed with high temperature curing test. Subsequently, the feasibility of unmanned construction method of filler material by pumping, and by movable bucket, are comparatively discussed through a real size demonstration.