Title:
Effect of Diutan Gums and Superplasticizers on the Rheology of Cement-Based Grouts
Author(s):
Mohammed Sonebi, Jacek Kwasny, and M. A. H. Jumahat
Publication:
Symposium Paper
Volume:
288
Issue:
Appears on pages(s):
1-12
Keywords:
chemical slump flow; plastic viscosity; superplasticizer; viscosity-modifying admixture; yield stress.
DOI:
10.14359/51684224
Date:
9/14/2012
Abstract:
The viscosity-modifying admixtures (VMAs) contribute to the control of the rheology of grout and are used to enhance plastic viscosity, cohesion, stability, and resis¬tance to bleeding of cement-based systems. This paper reports the results of an investiga¬tion on the effect of VMAs, namely two types of diutan gums and a welan gum, on the rheology behavior of cement grouts. All mixtures were made with two types of superplas¬ticizers. The dosages VMAs were 0.05%, 0.10% and 0.15% with a fixed water-to-cement ratio of 0.40. The investigated fresh properties of the grouts included the mini-slump flow, Marsh cone flow time, plate cohesion, and rheology parameters: namely yield value and the plastic viscosity. Both rheological parameters were obtained using coaxial and vane viscometers. Two control grouts (with and without superplasticizer) were also tested and compared to mixtures containing VMAs. The results indicated that both types of diutan gums were better in controlling the grouts fresh properties and rheology compared to the welan gum.