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Karen Scrivener

Cette personne a quitté l’EPFL

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Publications associées (264)

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Quantitative microstructural characterisation of cement paste submitted to different moderate temperature and loading conditions

Karen Scrivener

The temperature is known to influence the strength and durability of concrete. Temperature has also a great influence on the creep of cementitious materials. Previous investigations have not provided a complete understanding of these effects; in particular ...

2009

Water Redistribution-Microdiffusion in Cement Paste under Mechanical Loading Evidenced by H-1 NMR

Karen Scrivener

The mobility of water within the microstructure of hardened cement paste has been at the center of a long-lasting debate, motivated by the need to understand the fundamental mechanisms that play a role in drying, shrinkage, creep, and thermal expansion. Ou ...

2019

Suitability of Excavated London Clay from Tunnelling Operations as a Supplementary Cementitious Material and Expanded Clay Aggregate

Karen Scrivener, Franco Alberto Zunino Sommariva

London Clay is a marine geological formation that is relatively abundant in the London Basin area in the United Kingdom. It primarily originates from reworked Jurassic shale, greensand and chalk and lateritic Eocene soils with a mineralogy consisting of ka ...

2025

Increasing the kaolinite content of raw clays using particle classification techniques for use as supplementary cementitious materials

Karen Scrivener, Franco Alberto Zunino Sommariva

The adoption of blended cements to reduce the carbon footprint has increased significantly over the last decades. Clays containing kaolinite are a promising choice due to their widespread availability. Kaolinite content is the major factor controlling the ...

ELSEVIER SCI LTD2020

Evolution of microstructural changes in cement paste during environmental drying

Karen Scrivener, Fabien Jacques Michel Georget, Hamed Maraghechi, Wioletta Soja

Exposure of concrete to the atmosphere changes the microstructure of the cement paste. However, knowledge about the alteration of the porosity due to drying is typically not considered in deterioration processes of the hardened cement paste. The purpose of ...

Pergamon-Elsevier Science Ltd2020

The influence of the filler effect on the sulfate requirement of blended cements

Karen Scrivener, Franco Alberto Zunino Sommariva

In some blended cements, the optimum amount of sulfate addition differs from that observed in OPC. This study aims to understand the mechanism behind the impact of two SCMs, namely metakaolin and limestone, on the sulfate balance of blended cements. No sig ...

Pergamon-Elsevier Science Ltd2019

Hydration and mixture design of calcined clay blended cements: review by the RILEM TC 282-CCL

Karen Scrivener, Franco Alberto Zunino Sommariva, Mohsen Ben Haha, François Henri Avet

The RILEM technical committee 282-CCL: Calcined Clays as Supplementary Cementitious Materials, investigates all the aspects related to calcined clays, from clay exploration and characterization to calcination process, hydration reactions and concrete prope ...

SPRINGER2022

Basic creep of limestone-calcined clay cements: An experimental and numerical approach

Karen Scrivener, Julien Ston

This article presents a study on the creep properties of limestone calcined clay cement. A series of paste samples using limestone and calcined clays as replacement materials were tested under basic compressive creep. The ternary mixes showed a lower creep ...

ELSEVIER2019

Interactions between alite and C(3)A-gypsum hydrations in model cements

Karen Scrivener, Alexandra Quennoz

This paper focuses on the interactions that occur between cement phases during early hydration, especially between the hydration of alite and C(3)A-gypsum. This study shows that alite reaction is accelerated in the presence of gypsum. This acceleration was ...

Pergamon-Elsevier Science Ltd2013

Impact of water activity on the stability of ettringite

Karen Scrivener

The stability of ettringite as function of temperature and water vapour pressure was studied on synthetic samples using X-ray diffraction, thermogravimetric analysis, sorption balance measurements and different calorimetry techniques. Crystalline ettringit ...

Pergamon-Elsevier Science Ltd2016

Characterization of interfacial transition zone in concrete prepared with carbonated modeled recycled concrete aggregates

Karen Scrivener

Treatment by accelerated carbonation has been widely studied to enhance the quality of recycled concrete aggregates (RCA) and hence the performance of new concrete produced with the RCA. This is often ascribed to the densification of RCA. This study invest ...

Pergamon-Elsevier Science Ltd2020

Atomic-Level Structure of Zinc-Modified Cementitious Calcium Silicate Hydrate

Karen Scrivener, David Lyndon Emsley, Paul Bowen, Manuel Cordova, Pinelopi Moutzouri, Amrit Venkatesh, Ziga Casar, Anna Morales Melgares

It has recently been demonstrated that the addition of zinc can enhance the mechanical strength of tricalcium silicates (C3S) upon hydration, but the structure of the main hydration product of cement, calcium silicate hydrate (C-S-H), in zinc modified form ...

AMER CHEMICAL SOC2022

Investigation of phase formation, microstructure and mechanical properties of LC3 based autoclaved aerated blocks

Karen Scrivener

This study investigates the microstructure, phase formation, and mechanical properties of LC3-50 based auto-claved aerated blocks. The microstructure and phase formation is studied using SEM-EDS and X-ray diffraction techniques. The fresh and hardened prop ...

ELSEVIER SCI LTD2022

Surface properties of clinker phases and clay minerals characterized by inverse gas chromatography (IGC) and their link to reactivity

Karen Scrivener, Paul Bowen, Franco Alberto Zunino Sommariva

This paper presents a preliminary study of the characterization of the surface energy properties of clinker phases (C3S and C3A), kaolin and metakaolin by Inverse Gas Chromatography (IGC). For this, a reliable measurement methodology was developed. By look ...

Pergamon-Elsevier Science Ltd2024

Influence of curing temperature on cement paste microstructure measured by H-1 NMR relaxometry

Karen Scrivener, Arnaud Charles Albert Muller

H-1 nuclear magnetic resonance (NMR) relaxometry, supported by X-Ray diffraction and thermogravimetric analysis, has been used to characterise microstructure of white cement pastes underwater cured at temperatures in the range 10 degrees C to 60 degrees C. ...

Pergamon-Elsevier Science Ltd2019

Influence of Low- to Medium-Kaolinite Clay on the Durability of Limestone Calcined Clay Cement (LC3) Concrete

Karen Scrivener

The kaolinite content is principally responsible for the durability performance of Limestone Calcined Clay Cement (LC3), which calls into question its global applicability. The clay supply has a significant impact on the LC3 system's reduced carbon footpri ...

MDPI2023

Advances in understanding hydration of Portland cement

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

A 3D lattice Boltzmann effective media study: understanding the role of C-S-H and water saturation on the permeability of cement paste

Karen Scrivener, Mohamad Zalzale

A 3D lattice Boltzmann model is developed and used to calculate the water and gas permeabilities of model cement pastes at different degrees of water saturation. In addition to permeable micron-sized capillary pores and impermeable solid inclusions, the la ...

Institute of Physics2013

Understanding the negative effects of alkalis on long-term strength of Portland cement

Karen Scrivener, Franco Alberto Zunino Sommariva

It has long been known that alkalis favor an increase in the early strength of cementitious materials but have a negative impact on long-term strengths. The reasons for the negative effect on later strengths are not clear. In this paper we investigated the ...

Pergamon-Elsevier Science Ltd2023

Microstructural modelling of autogenous shrinkage in Portland cement paste at early age

Karen Scrivener, Quang Huy Do

Purpose ...

EMERALD GROUP PUBLISHING LTD2020