Title:
Methodology to Couple Time-Temperature Effects on Rheology of Mortar
Author(s):
Jean-Yves Petit, Kamal H. Khayat, and Eric Wirquin
Publication:
Materials Journal
Volume:
105
Issue:
4
Appears on pages(s):
342-349
Keywords:
cement hydration; chemical admixtures; plastic viscosity; rheology; self-consolidating concrete; temperature; yield stress
DOI:
10.14359/19895
Date:
7/1/2008
Abstract:
The evolution of rheological properties of cement-based materials during the dormant period of cement hydration depends on the coupled effect of temperature and time. Highly flowable concrete is increasingly being used to facilitate construction. Such concrete should be optimized to account for changes in workability during transport and placement at different temperatures. This paper presents a methodology to combine the influence of time and temperature on the variations of rheological properties of cement-based materials. Such variations are expressed as a function of a relative time scale deduced from calorimetric measurements. Four micromortars were prepared at temperatures of 10 to 30 °C (50 to 86 °F) and tested to determine the evolution of rheological properties over the dormant period of cement hydration. The apparent yield stress and plastic viscosity are shown to vary in linear fashion with the relative time scale that combines time and temperature during the dormant periods for the tested micromortars.