Super long period durability evaluation of concrete. Role and development of durability in cementitious materials

Some items for evaluation of cement and concrete materials used as an artificial barrier of radioactive waste geological disposal facilities are stated. The principle conditions and construction of the radioactive waste geological disposal facilities, evaluation of cut-off wall of concrete facilities, deterioration of cement materials, the effects of alkaline substances from cement materials and some future research subjects are described. Natural and artificial barriers of radioactive waste geological disposal facility, the low-level radioactive disposal facility, a type of radioactive disposal and performance of the facility, histogram of average crack width and the maximum crack width, outline of permeability test of RC structure, distribution of water content of side wall of samples of permeability test, the results of GMT project, crack of full scale mortar sidewall, model analysis of dissolution phenomena of cement materials, EPMA analysis results of Ca/Si ratio of cements after dipping, and the evaluation method of interaction between cement and bentonite are illustrated. (S.Y.)