MODELLING OF AGEING OF LOW-PH CONCRETES

Author(s): Laurie Buffo-Lacarrière, Youssef El Bitouri, Alain Sellier, Xavier Bourbon
Paper category: Proceedings
Book title: proceedings of the International RILEM Conference on Materials, Systems and Structures in Civil Engineering Conference segment on Service Life of Cement-Based Materials and Structures
Editor(s): Miguel Azenha, Ivan Gabrijel, Dirk Schlicke, Terje Kanstad and Ole Mejlhede Jensen
ISBN:978-2-35158-171-4
e-ISBN: 978-2-35158-173-5
Publisher: RILEM Publications SARL
Publication year: 2016
Pages: 425-434
Total Pages: 10
Language : English

Abstract: A model of chemo-mechanical evolution of new cementitious materials such as low-pH
cements is described. The proposed phenomenological model, usable at structure scale, is
based at early age on a multiphasic hydration developed for blended cements. At higher ages,
the evolution of mechanical properties of such binder with high silica content cannot be
explained by pozzolanic reaction (because portlandite is entirely consumed at early ages). At
these ages, mineralogy analyses showed that the hydration of remaining anhydrous silica
oxide is still developing by consumption of calcium from hydrates with high C/S ratios (for
instance C-S-H produced by clinker hydration at early age). These chemical evolutions are
modeled taking into account chemical equilibrium of solution and solid phases in terms of
calcium concentration. The impact on mechanical properties is then also predicted. Finally the
chemo-mechanical model is applied on the prediction of mechanical behavior of nuclear
waste storage structures casted with low pH based concrete.

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