Abstract
Characterization of powder is essential for proportioning the self-compacting concrete. In particular, the capability of water retention is the most basic parameter for the characterization. This paper deals with what properties of powder affect the water retention capacity mostly and how they do. Out of several factors, particle shape and distribution of particle size are selected as key factors, and they are characterized by introducing a shape factor and a statistic measure. It is concluded that those factors are effective to make a quantitative representation of how particles are packed in a unit volume, and then, to construct a model how water is retained on the surface of particles.
