Publications de Cyrille Dunant

Microstructural simulation and measurement of elastic modulus evolution of hydrating cement pastes

Cyrille Dunant, Karen Scrivener, Arnaud Müller, Arnaud Charles Albert Muller

Predicting the evolution of stiffness in cement paste requires linking morphological properties of the microstructure to the evolution of mechanical properties. Measures are typically difficult to obtain with sufficient time resolution to capture the trans ...

Pergamon-Elsevier Science Ltd2020

Impact of temperature on expansive behavior of concrete with a highly reactive andesite due to the alkali-silica reaction

Cyrille Dunant, Karen Scrivener

The influence of temperature on the expansive behavior and microstructural damage of concrete due to the alkali-silica reaction (ASR) is studied experimentally by applying a new testing protocol, the Alkali-Wrapped Concrete Prism Test (AW-CPT). Early-stage ...

Pergamon-Elsevier Science Ltd2019

Characterization of Fly Ashes by a Novel Method in the Scanning Electron Microscope

Cyrille Dunant, Mohsen Ben Haha, Karen Scrivener, Pawel Tadeusz Durdzinski

In this paper, we show a new technique to characterize fly ashes using scanning electron microscopy (SEM). Chemical composition of millions of points is measured by SEM-energy dispersive X-ray spectroscopy and plotted in a ternary frequency plot. This new ...

ASTM INTERNATIONAL2019

Physically based models to study the alkali-silica reaction

Cyrille Dunant, Karen Scrivener

The Laboratory of Construction Materials in Lausanne has been studying the alkali-silica reaction for more than 10 years, advancing the understanding of the reaction, and also producing microstructural models which can be used to predict quantitatively the ...

Ice Publishing2016

Influence of visco-elasticity on the stress development induced by alkali-silica reaction

Cyrille Dunant, Karen Scrivener, Alain Benjamin Giorla

The alkali-silica reaction causes long-term degradation in the microstructure of affected concrete as well as macroscopic expansion. In this paper, a micro-mechanical model based upon an explicit representation of the microstructure has been used to simula ...

Pergamon-Elsevier Science Ltd2015

A new quantification method based on SEM-EDS to assess fly ash composition and study the reaction of its individual components in hydrating cement paste

Cyrille Dunant, Mohsen Ben Haha, Karen Scrivener, Pawel Tadeusz Durdzinski

Calcareous fly ashes are high-potential reactive residues for blended cements, but their qualification and use in concrete are hindered by heterogeneity and variability. Current characterization often fails to identify the dominant, most reactive, amorphou ...

Pergamon-Elsevier Science Ltd2015

Fly ash as an assemblage of model Ca-Mg-Na-aluminosilicate glasses

Cyrille Dunant, Mohsen Ben Haha, Karen Scrivener, Pawel Tadeusz Durdzinski, Ruben Anton Snellings

Model Ca-Mg-Na-aluminosilicate glasses based on compositions found in a calcareous fly ash were synthesised and their reactivity assessed in NaOH solution and in Portland cement paste. It was found that the reactivity followed the same trend in both system ...

Pergamon-Elsevier Science Ltd2015

Alkali-silica reaction: Current understanding of the reaction mechanisms and the knowledge gaps

Cyrille Dunant

Alkali-silica reaction (ASR) is a major concrete durability problem, resulting in significant maintenance and reconstruction costs to concrete infrastructures all over the world. Despite decades of study, the underlying chemical and physical reaction mecha ...

Pergamon-Elsevier Science Ltd2015

Finite elements in space and time for the analysis of generalised visco-elastic materials

Cyrille Dunant, Karen Scrivener, Alain Benjamin Giorla

Numerical analysis of linear visco-elastic materials requires robust and stable methods to integrate partial differential equations in both space and time. In this paper, symmetric space-time finite element operators are derived for the first time for elem ...

Wiley-Blackwell2014

A critical comparison of several numerical methods for computing effective properties of highly heterogeneous materials

Cyrille Dunant, Alain Benjamin Giorla

Modelling transport and long-term creep in concrete materials is a difficult problem when the complexity of the microstructure is taken into account, because it is hard to predict instantaneous elastic responses. In this work, several numerical methods are ...

Elsevier Sci Ltd2013

Effects of uniaxial stress on alkali-silica reaction induced expansion of concrete

Cyrille Dunant, Karen Scrivener

ASR affected concrete in real structures is usually subject to loads which affect the macroscopic expansion of the material. An experimental study was undertaken using sensors embedded in reactive and non-reactive samples loaded on modified creep frames. N ...

Pergamon-Elsevier Science Ltd2012

Effects of aggregate size on alkali-silica-reaction induced expansion

Cyrille Dunant, Karen Scrivener

The macroscopic effects of ASR are linked to the damage state at the microstructure level. In this paper we used a combination of experiments and modelling to study the effect of aggregate size on the manifestation of ASR. There are two main ways in which ...

Pergamon-Elsevier Science Ltd2012

An algorithm to compute damage from load in composites

Cyrille Dunant, Karen Scrivener

2011

Micro-mechanical modelling of alkali-silica-reaction-induced degradation using the AMIE framework

Cyrille Dunant, Karen Scrivener

AMIE. a finite element/extended finite element framework, has been designed to provide the tools to run detailed microstructural simulations; this paper demonstrates the possibility of simulating the mechanisms underlying the alkali-silica-reaction (ASR). ...

Pergamon-Elsevier Science Ltd2010

Decoupling method for heat evolution curves of model cements - Influence of the presence of C3A-gypsum on the alite hydration

Cyrille Dunant, Karen Scrivener, Emmanuel Gallucci, Alexandra Quennoz

2010

Influence of the gypsum amount on the hydration of tricalcium aluminate in C3A-gypsum and in alite-C3A-gypsum systems

Cyrille Dunant, Karen Scrivener, Emmanuel Gallucci, Alexandra Quennoz

2009

Experimental and modelling study of the alkali-silica-reaction in concrete

Cyrille Dunant

The alkali-silica reaction (ASR) is a durability issue of concrete. The amorphous silica of aggregates reacts with the alkalies present in the cement paste pore solution to form a hydrophilic gel which swells in the presence of moisture. Many mass concrete ...

EPFL2009

Hematopoietic Stem Cells Reversibly Switch from Dormancy to Self-Renewal during Homeostasis and Repair

Cyrille Dunant, Maike Jaworski, Sandra Eloise Kjeldsen, Anne Wilson

Bone marrow hematopoietic stem cells (HSCs) are crucial to maintain lifelong production of all blood cells. Although HSCs divide infrequently, it is thought that the entire HSC pool turns over every few weeks, suggesting that HSCs regularly enter and exit ...

2008