Reducing cement paste volume for production of self-consolidating concrete by adding fillers

Abstract

For the production of self-consolidating concrete (SCC), in order to achieve high flowability and high cohesiveness at the same time, it is often necessary to provide a fairly large cement paste volume of up to 35%. Such a large cement paste volume would lead to high cement consumption, low dimensional stability and a high carbon footprint. This paper presents a study on the feasibility of reducing the cement paste volume by adding fillers to the concrete mix. Two types of fillers, namely, limestone fines (LF) and ground sand (GS), were used. Trial concrete mixes with various amounts of LF and GS added were produced for slump flow, passing ability, sieve segregation and compressive strength tests. The results revealed that although the addition of fillers would substantially increase the superplasticiser demand, it would allow the cement paste volume to be reduced to as low as 25% while still meeting the slump flow, passing ability and segregation resistance requirements of SCC.