Rl. Day et C. Shi, INFLUENCE OF THE FINENESS OF POZZOLAN ON THE STRENGTH OF LIME NATURAL-POZZOLAN CEMENT PASTES, Cement and concrete research, 24(8), 1994, pp. 1485-1491
Citations number
11
Categorie Soggetti
Construcion & Building Technology","Material Science
The fineness of a cement is an important factor affecting the rate of
strength development. This paper examines the importance of the finene
ss of natural pozzolans to the strength development of lime-pozzolan c
ements (LPCs). A natural pozzolan from Bolivia, which is typical of na
tural pozzolans found in South and Central America, was ground to vari
ous finenesses, blended with lime with a mass ratio of 80:20, and the
resulting LPC was used to make hardened cement paste cylinders. In som
e pastes 4% sodium sulphate or 4% sodium chloride activator was used t
o enhance strength development. Strengths of the cylinders were measur
ed at ages from 3 to 90 days during continuous moist curing at 50-degr
ees-C. The experimental results show that there is a good linear corre
lation between the Blaine fineness of the natural pozzolan and compres
sive strength at all ages and for all pastes. The fineness of the natu
ral pozzolan has its most significant effect on early strength gain. T
he addition of chemical activator increases both the rate of strength
gain and the sensitivity of strength gain to fineness.