Title: Low Heat Development in Self-Compacting Concretes for Massive Structures

Author(s): R. Troll, J. J. Ogoumah Olagot, S. Monosi, and M. Collepardi

Publication: Symposium Paper

Volume: 217

Issue:

Appears on pages(s): 103-112

Keywords: bleeding; fly ash; heat of hydration; self-compacting concrete; superplasticizer

DOI: 10.14359/12908

Date: 9/1/2003

Abstract:
Self-compacting concretes (SCC) are special cement mixes which can be placed without any vibration at all. The fresh mixes are characterized by very high fluidity and cohesion. These properties can be more easily obtained by decreasing the maximum size of the coarse aggregate and increasing the cement content. This characteristic is just the opposite of that required for concrete mixes for massive structures. These mixtures need coarse aggregate with high maximum size and low cement content in order to reduce the risk of thermal cracking related to the high heat development due to cement hydration. Special SCC have been studied. They contain a gravel with a maximum size of 18 mm, a very low cement content (- 150 kg/m3) a large amount of limestone filler (250-380 kg/m3) and fly ash in the range of 50-150 kg/m3 so that the amount of fine materials is approximately 500 kg/m3. Due to the combined use of an acrylic superplasticizer and a viscosity agent based on a colloidal byopolimeric emulsion, unsegregable SCC with a slump flow of about 700 mm were manufactured. The compressive strength was about 20 MPa at 3 days and 30-40 MPa at 28 days.