Title:
Monitoring and Evaluation of Cement Hydration by Semi-Adiabatic Field Calorimetry
Author(s):
J.P. Sandberg and S. Liberman
Publication:
Symposium Paper
Volume:
241
Issue:
Appears on pages(s):
13-24
Keywords:
cement-admixture interactions; cement hydration; compatibility; semi-adiabatic calorimetry; setting.
DOI:
10.14359/18648
Date:
4/1/2007
Abstract:
This paper describes the use of a recently developed, inexpensive portable semi-adiabatic calorimeter for monitoring cement hydration in concrete and mortar. The calorimeter measures the temperature as a function of time at the bottom of eight individual 3x6 cylinders with concrete or mortar. The measured temperature profile is used to evaluate the overall hydration performance of cementitious mixtures, with special emphasis on the timing and the size of the main hydration exotherms that strongly affect setting and early strength development of cementitious mixtures. Furthermore, a method has been developed for a more precise calculation of "thermal set", with good correlation to manual set times according to ASTM C403. The field calorimeter is useful to screen the effect of type and dosage of admixtures and supplementary cementitious materials on "thermal" setting times in concrete and mortar.