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Karen Scrivener

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Publications associées (271)

Influence of silica fume on the microstructure of cement pastes: New insights from H-1 NMR relaxometry

Karen Scrivener, Arnaud Charles Albert Muller

H-1 NMR has been used to characterise white Portland cement paste incorporating 10 wt.% of silica fume. Samples were measured sealed throughout the hydration without sample drying. Paste compositions and C-S-H characteristics are calculated based on H-1 NM ...

Pergamon-Elsevier Science Ltd2015

Limestone reaction in calcium aluminate cement–calcium sulfate systems

Karen Scrivener, Julien Bizzozero

This paper reports a study of ternary blends composed of calcium aluminate cement, calcium sulfate hemihydrate and limestone. Compressive strength tests and hydration kinetics were studied as a function of limestone and calcium sulfate content. The phase e ...

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

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

TC 238-SCM - hydration and microstructure of concrete with SCMs: State of the art on methods to determine degree of reaction of SCMs

Karen Scrivener, Barbara Lothenbach, Ruben Anton Snellings

This paper is the work of working group 2 of the RILEM TC 238-SCM. Its purpose is to review methods to estimate the degree of reaction of supplementary cementitious materials in blended (or composite) cement pastes. We do not consider explicitly the wider ...

Springer2015

Pozzolanic activity of mechanochemically and thermally activated kaolins in cement

Karen Scrivener, Mohammadhadi Kazemi Kamyab, Ruben Anton Snellings

This paper reports on the mechanochemical activation by intensive grinding as an alternative way to produce pozzolanically reactive metakaolin. The physicochemical properties, pozzolanic reactivity and impact on cement hydration of mechanochemically and th ...

Pergamon-Elsevier Science Ltd2015

Industrial trial to produce a low clinker, low carbon cement

Karen Scrivener, Leng Maday Vizcaino Andres, Abdel Perez Hernandez

A preliminary assessment of conditions for the industrial manufacture of a new cementitious system based on clinker-calcined clay and limestone, developed by the authors, referred as "low carbon cement" is presented. The new cement enables the substitution ...

Inst Ciencias Construccion Eduardo Torroja2015

Evolution of pore structure in blended systems

Karen Scrivener, Elise Marie Jeanne Berodier

In this study, the effect of SCM in the cement paste was isolated by using ternary systems combining Portland cement, quartz and SCM. The results show clear differences in how the hydrates from the reaction of clinker, slag and fly ash fill space. The reac ...

Pergamon-Elsevier Science Ltd2015

The influence of sodium salts and gypsum on alite hydration

Karen Scrivener, Thomas Matschei, Berta Mota Gassó

This work aims to clarify the impact of alkali and sulfate on the hydration kinetics and microstructural development of alite. The plain alite system is compared to systems with addition of: i) gypsum, ii) Na2SO4, iii) NaOH plus gypsum and iv) NaOH. In all ...

Pergamon-Elsevier Science Ltd2015

Advances in understanding hydration of Portland cement

Patrick Juilland, Karen Scrivener

Progress in understanding hydration is summarized. Evidence supports the geochemistry dissolution theory as an explanation for the induction period, in preference to the inhibiting layer theory. The growth of C-S-H is the principal factor controlling the m ...

Pergamon-Elsevier Science Ltd2015

Hydration states of AFm cement phases

Karen Scrivener, Mahsa Saeidpour, Thomas Matschei

The AFm phase, one of the main products formed during the hydration of Portland and calcium aluminate cement based systems, belongs to the layered double hydrate (LDH) family having positively charged layers and water plus charge-balancing anions in the in ...

Pergamon-Elsevier Science Ltd2015

Microstructural modelling of the elastic properties of tricalcium silicate pastes at early ages

Karen Scrivener, Shashank Bishnoi, Quang Huy Do

This paper describes the numerical calculation of elastic properties of a simulated microstructure of cement paste from very early age, when most previous models fail to give accurate results. The development of elastic properties of tricalcium silicate pa ...

Techno-Press2015

Incorporation of aluminium in calcium-silicate-hydrates

Karen Scrivener, Barbara Lothenbach, Émilie Michèle L'Hôpital

Calcium silicate hydrate (C-S-H) was synthetized at 20 degrees C to investigate the effect of aluminium uptake (Al/Si = 0-0.33) in the presence and absence of alkalis on the composition and the solubility of a C-S-H with a Ca/Si equal to 1.0. C-S-H incorpo ...

Pergamon-Elsevier Science Ltd2015

The Effect of Mg on Slag Reactivity in Blended Cements

Karen Scrivener, Ruben Anton Snellings

Blast-furnace slags are widely used as supplementary cementitious materials in blended cements because of their relatively high reactivity. This study describes the effect of substituting Ca by Mg on the reactivity of synthetic glass with similar compositi ...

Springer2014

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

Expansion mechanisms in calcium aluminate and sulfoaluminate systems with calcium sulfate

Karen Scrivener, Julien Bizzozero, Christophe Gosselin

The long-term expansion of calcium aluminate cement and calcium sulfoaluminate cement in the presence of added gypsum has been studied for samples cured under water. Progressively higher amounts of gypsum were added to the CAC or CSA and it was found that ...

Pergamon-Elsevier Science Ltd2014

The existence of amorphous phase in Portland cements: Physical factors affecting Rietveld quantitative phase analysis

Karen Scrivener, Amélie Bazzoni, Ruben Anton Snellings

Rietveld quantitative phase analysis has become a widespread tool for the characterization of Portland cement, both for research and production control purposes. One of the major remaining points of debate is whether Portland cements contain amorphous cont ...

Pergamon-Elsevier Science Ltd2014

Impact of Annealing on the Early Hydration of Tricalcium Silicate

Marco Cantoni, Karen Scrivener, Amélie Bazzoni

It was recently proposed that the induction period observed during the hydration of tricalcium silicate could be explained by the build-up of ions in solution. Due to the importance of defects in this mechanism, this work describes the effect of different ...

Wiley-Blackwell2014

Methods to determine hydration states of minerals and cement hydrates

Karen Scrivener, Mahsa Saeidpour, Thomas Matschei

This paper describes a novel approach to the quantitative investigation of the impact of varying relative humidity (RH) and temperature on the structure and thermodynamic properties of salts and crystalline cement hydrates in different hydration states (i. ...

Pergamon-Elsevier Science Ltd2014

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