Study of water transfer in cement interstices by 1H NMR relaxation time method

Sakata, Nagisa*; Tachi, Yukio  ; Iwadate, Yasuhiko*; Okubo, Takahiro*

Cement-based materials will be used as a component for radioactive waste disposal facility. Understanding water paths in cement-based materials is a key to evaluate their long-term performance. It is well known that 1H transverse relaxation (T2) of water filled pores is related to their porous structure. In this study, 1H T2 distribution analyses were applied to hydration process of cement-based materials, and the relationship between porous structure and mass transport was discussed. Experimental results showed that the main path of water is the grain boundary between cement and silica sand contained in mortar. In addition, C-S-H gel layers in cement and C-S-H gel pore cannot contribute as a path of water.