Effect of Cement Particle Size on the Compressive Strength and Other Physiochemical Properties of Portland Cement

ABSTRACT

The effect of cement particle size of Portland cement on the

properties of cement mortar and paste were investigated. This

was done at a definite mix and water-cement ratio. Fresh clinkers

collected from Dangote Cement Factory was ground together with

3% gypsum using disc grinder. The chemical compositions of the

clinker and gypsum were determined using XRF. Five different

sieve sizes comprising (212, 180, 90, 63, 45) m were used to

characterize the cement sample fineness. Three samples from

each of the sieve sizes were used to produce mortar block of

(40x40x160)mm prism as specified by European standard, These

were used to test for compressive strength for different days.

Other experimental processes were conducted according to

standard procedures. The resultant pastes were then subjected to

physiochemical analysis. When compared with NIS values of 16.0 N/mm2 and 32.5 N/mm2 for 7th and 28th day age respective

strength. It was found that at 2nd day age 45 m size could give strength value obtainable in NIS specification while at 7th day,(63 and 45 m size gave acceptable strength values and at 28th day

(90,63 and 45 m yielded good values. Hence, compressive strength of cement mortar generally increases with increasing fineness and likewise increase in fineness yielded better physiochemical properties. However, graphs plotted did not give a linear relationship, showing that other factor like oxide composition and burning conditions also affect the strength Also, results obtained from tests on strength property of cement from other cement manufacturing companies showed that some have better strength quality than others.

Key words: Compressive strength, clinker, gypsum, mortar, fineness.