Title:
Rheological Method to Evaluate Structural Buildup in Self-Consolidating Concrete Cement Pastes
Author(s):
Raissa P. Ferron, Amedeo Gregori, Zhihui Sun, and Surendra P. Shah
Publication:
Materials Journal
Volume:
104
Issue:
3
Appears on pages(s):
242-250
Keywords:
rheology; self-consolidating concrete; thixotropy
DOI:
10.14359/18669
Date:
5/1/2007
Abstract:
Much research has focused on determining the rheological properties of cementitious materials, but limited information can be found on the influence of thixotropy in affecting the flow properties of these materials. A protocol consisting of hysteresis loops and energy methods, was developed to quantify the degree of structural rebuilding in cement pastes. This protocol takes into account the stiffening due to thixotropic rebuilding and irreversible structural changes by focusing on the rate in which the cement paste is able to regain its internal structure after shearing. The protocol was used to evaluate the rebuilding potential of 23 cement paste mixtures of various binder type and fluidity level. Results show that structural build up can be controlled through selection of proper powder type, high-range water-reducing admixture, and water-tobinder ratio (w/ b).