Rheological characterization of self-compacting concrete - a critical analysis

Author(s): L. Sanchez, R.C. de Oliveira Romano, D.A. dos Santos, V.M. John, R.G. Pileggi
Paper category: Symposium
Book title: 3rd International RILEM Symposium on Rheology of Cement Suspensions such as Fresh Concrete
Editor(s): O.H. Wallevik, S. Kubens, S. Oesterheld
ISBN: 978-2-35158-091-2
e-ISBN: 978-2-35158-092-9
Pages: 79 - 87
Total Pages: 9
Language: English

Abstract: 
The characterization and the quality control of plastic concretes in the fresh state is usually carried out through conventional single-point tests as slump or slump-flow and in a very special cases, this characterization is complemented by density and content of air. However, rheological concepts and rheometric techniques applied to concrete technology clearly demonstrate that single-point tests do not describe the rheological behavior of fresh concretes.
This paper presents the rheological characterization of distinct self compacting concretes, prepared with the same particle size distributions, but using two different types of cement and distinct time delay for superplasticizer addition. The tests were carried out in a novel rheometer developed for concretes and the results were compared with those obtained from traditional slump and slump-flow tests.
The results demonstrated the exchange of cement type and time elapsed for admixture addition affected the rheological behavior of concretes. Moreover, an unusual behavior regarding to the equivalent yield stress and the viscous flow profile of the tested systems was observed, which cannot be identified by single-point tests.

Online publication: 2009
Publication Type: full_text
Public price (Euros): 0.00