DISSOLUTION KINETICS EXPERIMENTS AS A METHOD TO ASSESS THE REACTIVITY OF SUPPLEMENTARY CEMENTITIOUS MATERIALS (SCMS): THE EFFECT OF SOLUTION COMPOSITION AND SCM STRUCTURE

Author(s): Snellings, R. and Scrivener, K.
Paper category: Conference
Book title: XIII International Conference on Durability of Building Materials and Components - XIII DBMC
Editor(s): Marco Quattrone, Vanderley M. John
Print ISBN: none
e-ISBN: 978-2-35158-149-0
Publication year: 2015
Pages: 134-141
Total Pages: 8
Language: English

Abstract: One of the most effective ways to improve the sustainability of cement production is the blending of Portland clinker with SCMs. However SCMs are less reactive than clinker so leading to slower development of strength and other properties. This limits the amount which can be substituted. Better understanding of the intrinsic reactivity of SCMs would facilitate the formulation of better and more sustainable blended cements.

Direct measurements of the reactivity or the degree of reaction of a SCM in a hydrating cement paste are a complicated task. Separating the contribution of the SCM reaction from the complex interplay of cement hydration reactions is not straightforward and the direct quantification of the amount of unreacted SCM may be hindered by issues such as SCM fineness or crystallinity. Therefore a better approach could be to breakdown the hydration of blended cements by analysing separate reactions in simplified model systems. This approach presents the added advantage of enabling the variation of individual parameters such as SCM or pore solution composition without affecting the hydration of the clinker phases.

This contribution presents a comprehensive study of the reactivity of a range of synthetic SCMs by dissolution experiments at high dilution and varying pH and links the obtained results to the hydration of the same SCMs in blended cements. The results show a strong dependence of the SCM reactivity and surface chemistry on pore solution composition and deliver insights that pave the way to actively enhancing the reactivity of SCMs in cement.

Online publication: 2015
Publication Type: full_text
Public price (Euros): 0.00