Title: Strength and Durability of Concretes with Slag-Fly Ash-Portland Cement

Author(s): A. Borsoi, S. Collepardi, L. Coppola, R. Troli, and M. Collepardi

Publication: Symposium Paper

Volume: 199

Issue:

Appears on pages(s): 115-126

Keywords: carbonation; chloride penetration; composite cement; compressive strength; fly ash; slump; slump loss; slag superplasti-cizer

DOI: 10.14359/10487

Date: 6/1/2001

Abstract:
Composite cements containing portland cement (50%), fly ash (25%) and slag (25%), all interground at a Blaine fineness of about 400 or 500 m2/kg, were produced. Super-plasticized concretes with a slump of 200-230 mm were manufactured by using sulfonated naphthalene (SN) or acrylic polymer (AP). The dosage of super-plasticizers was a little higher (10% more) when finer cements were used. The AP superplasticizer was more effective than that based on SN in terms of lower dosage (20% less) and lower water-cementitious material ratio (10% less) at equal workability. Consequently, higher compressive strength were obtained for concretes with the AP admixture rather than with the N S superplasticizer. The better performance of the AP superplasticizer with respect to the SN admixture was independent of the curing temperature (5 or 20) at early (1 day) and later ages (28-90 days). All the concrete mixtures perform very well for the durability behavior in terms of lower CO2 penetration and chloride diffusion. However, due to the lower water-cementitious material ratio (0.29 vs. 0.32) concretes with the acrylic polymer are potentially more durable than those with the naphthalene-based superplasticizer.