Examining hydration kinetics obtained from different mixing procedures using isothermal calorimetry

Author(s): Oskar Linderoth and Lars Wadsö
Paper category: Proceedings of the International RILEM Conference Materials, Systems and Structures in Civil Engineering 2016 Segment on Fresh Concrete
Editor(s): Lars N. Thrane, Claus Pade, Oldrich Svec and Nicolas Roussel
ISBN: 978-2-35158-184-1
e-ISBN: 978-2-35158-185-8
Publisher: RILEM Publications SARL
Publication year: 2016
Pages: 106-115
Total Pages: 10
Language : English

Abstract: Mixing large batches of concrete is time consuming yet necessary for many studies in cement and concrete research, because the behavior and properties of mortar or paste mixed on a smaller scale is not the same as for concrete, for example when testing the compressive strength. At the same time, many scientific tests only require a few grams – or even milligrams - of sample, so a large part of a concrete batch will go to waste. The idea of this work is to use isothermal calorimetry and different mixing methods in order to compare the hydration kinetics of concrete, mortar and cement paste. To do so the hydration curve has been examined and interesting points along it have been identified. The goal of the study is to find what governs the shape of the curve. If we can understand how the hydration is affected by the mixing procedure then we can possibly find suitable mixing methods that allow us to mix smaller samples that have the kinetics of larger concrete mixes. The use of small samples, mortar or cement paste, would significantly lower the time consumption when testing, e.g., a large matrix of cements and water-binder ratios. The samples could also be mixed in the chemical laboratory instead of being taken from a concrete mixer. This can for example be of interest for thermogravimetric measurements of degree of hydration and for the determination of cement paste pore structure

Online publication : 2016
Publication type : full_text
Public price (Euros) : 0.00