Abstract: Fly ash cement samples with different specific surface area were prepared from Portland cement clinker and flay ash with different specific surface area. Mortar strength development of the fly ash cement and the particle size distribution of the clinker and fly ash were measured respectively, then the gray correlation analysis was carried out on the properties of cement mortar with the particle size distribution of clinker and fly ash. The results showed that clinker particles with size 0-30 μm correlated with the properties of cement positively, and those with size lager than 30 μm correlated with the properties of cement negatively, among which clinker particles with size between 10-20 μm contributed the most to the strength development of cement mortar. Fly ash particles with size 0- 40 μm correlated with the properties of cement positively, thus being more actively, and those with size lager than 40 μm correlated with the properties of cement negatively, contributed less to the strength development of cement mortar.

Key words: clinker%fly ash%particle size distribution%gray correlation analysis