Publications by Barbara Lothenbach

Influence of temperature on phase assemblages of belite-ye'elimite cement

Karen Scrivener, Barbara Lothenbach, Natechanok Chitvoranund, Diana Londoño Zuluaga

This paper studies the effect of temperature on the phase assemblages of belite-ye'elimite cement. A comparison is made between thermodynamic modelling and experimental data at 28 and 180 days of hydration at 5, 20, 40, and 60 degrees C. The fast reaction ...

Pergamon-Elsevier Science Ltd2023

Effect of different ions on dissolution rates of silica and feldspars at high pH

Karen Scrivener, Barbara Lothenbach, Mahsa Bagheri, Mahdieh Shakoorioskooie

The dissolution kinetics of silica-containing minerals in aggregates influences strongly the process of ASR in concrete. In this paper, the effect of different ions on the dissolution rates of SiO2 (amorphous and quartz) and feldspars at high pH values was ...

Pergamon-Elsevier Science Ltd2022

A long-term study on structural changes in calcium aluminate silicate hydrates

Christian Ludwig, Barbara Lothenbach, Sonya Barzgar, Yu Yan, Mohamed Tarik

Production of blended cements in which Portland cement is combined with supplementary cementitious materials (SCM) is an effective strategy for reducing the CO2 emissions during cement manufacturing and achieving sustainable concrete production. However, t ...

SPRINGER2022

The effect of paste composition, aggregate mineralogy and temperature on the pore solution composition and the extent of ASR expansion

Karen Scrivener, Barbara Lothenbach, Mahsa Bagheri

The reaction kinetics of the alkali silica reaction depends on the composition of the pore solution. The evolution of the pore solution composition in different cement pastes and concretes was studied. Pastes containing silica fume or metakaolin had the lo ...

SPRINGER2022

Al uptake in calcium silicate hydrate and the effect of alkali hydroxide

Karen Scrivener, Yan Yan, Barbara Lothenbach

The effect of Al and of pH on the structure of calcium silicate hydrate (C-S-H), the most important hydration product in Portland and blended cement, was studied at Ca/Si similar to 1.0. The presence of Al led to higher amounts of secondary phases, larger ...

Pergamon-Elsevier Science Ltd2022

Effect of alkali hydroxide on calcium silicate hydrate (C-S-H)

Karen Scrivener, Barbara Lothenbach, Émilie Michèle L'Hôpital, Sheng-Yu Yang, Yu Yan

This paper investigates the effect of KOH and NaOH on C-S-H structure and solubility. Both KOH and NaOH have a similar effect, they increase pH values and silicon concentrations, and decrease calcium concentrations. At higher alkali hydroxide concentration ...

Pergamon-Elsevier Science Ltd2022

Predicting damage in aggregates due to the volume increase of the alkali-silica reaction products

Jean-François Molinari, Barbara Lothenbach, Emil Gallyamov

Volume increase between the reactants and the products of alkali silica reaction could reach up to 100%. Taking place inside the aggregates, ASR imposes internal pressure on the surrounding material. In the current paper, we study the possibility of crack ...

Pergamon-Elsevier Science Ltd2022

Understanding the carbonation of concrete with supplementary cementitious materials: a critical review by RILEM TC 281-CCC (vol 53, 136, 2020)

Karen Scrivener, Barbara Lothenbach

A correction to this paper has been published: https://doi.org/10.1617/s11527-020-01558-w ...

SPRINGER2021

The effect of equilibration time on Al uptake in C-S-H

Christian Ludwig, Barbara Lothenbach, Sonya Barzgar, Mohamed Tarik

Pergamon-Elsevier Science Ltd2021

The effect of sodium hydroxide on Al uptake by calcium silicate hydrates (C S H)

Christian Ludwig, Barbara Lothenbach, Sonya Barzgar, Alessio Di Giacomo, Mohamed Tarik

To reduce the CO2 emissions from cement production, Portland cement (PC) is partially replaced by supplementary cementitious materials (SCM). Reactions of SCM with PC during hydration leads to the formation of CSH with more silicon and aluminum than in PC, ...

2020

Understanding the carbonation of concrete with supplementary cementitious materials: a critical review by RILEM TC 281-CCC

Karen Scrivener, Barbara Lothenbach

Blended cements, where Portland cement clinker is partially replaced by supplementary cementitious materials (SCMs), provide the most feasible route for reducing carbon dioxide emissions associated with concrete production. However, lowering the clinker co ...

SPRINGER2020

Inside Back Cover

Christian Ludwig, Barbara Lothenbach, Sonya Barzgar, Alessio Di Giacomo, Mohamed Tarik

2020

Report of TC 238-SCM: hydration stoppage methods for phase assemblage studies of blended cements-results of a round robin test

Karen Scrivener, Barbara Lothenbach, Pawel Tadeusz Durdzinski, Ruben Anton Snellings, Yuvaraj Dhandapani

2018

Outcomes of the RILEM round robin on degree of reaction of slag and fly ash in blended cements

Mohsen Ben Haha, Karen Scrivener, Barbara Lothenbach, Pawel Tadeusz Durdzinski

Working group 2 of the RILEM TC 238-SCM undertook a comparison of laboratories and techniques for the quantification of the degree of reaction of supplementary cementitious materials in blended cements. A common set of binary pastes of Portland cement with ...

Springer Verlag2017

The pore solution of blended cements: a review

Barbara Lothenbach, Ruben Anton Snellings

This paper is the work of working group 3 of the RILEM Technical Committee on Hydration and Microstructure of Concrete with SCM (TC 238-SCM). The pore solution is an essential but often overlooked part of hydrated cements. The composition of the cement por ...

Springer2016

Influence of calcium to silica ratio on aluminium uptake in calcium silicate hydrate

Karen Scrivener, Barbara Lothenbach, Émilie Michèle L'Hôpital

Aluminium uptake in calcium silicate hydrate (C-S-H) was studied at different Ca/Si ratios from 0.6 to 1.6 at 20 degrees C. Aluminium incorporation in C-S-H depends on the total amount of aluminium present in the sample. At low Al/Si ratio (

Pergamon-Elsevier Science Ltd2016

Alkali uptake in calcium alumina silicate hydrate (C-A-S-H)

Karen Scrivener, Barbara Lothenbach, Émilie Michèle L'Hôpital

Uptake of the alkalis K and Na by calcium silicate hydrate (C-S-H) and calcium alumina silicate hydrate (C-A-S-H) of molar Ca/Si ratios = 0.6 to 1.6 and molar Al/Si ratio = 0 or 0.05 has been studied at 20 degrees C. Alkalis are thought to be bound in the ...

Pergamon-Elsevier Science Ltd2016

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

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

Composite membranes for alkaline electrolysis based on polysulfone and mineral fillers

Barbara Lothenbach, Andreas Züttel

Mineral-based membranes for high temperature alkaline electrolysis were developed by a phase inversion process with polysulfone as binder. The long-term stability of new mineral fillers: wollastonite, forsterite and barite was assessed by 8000 h-long leach ...

Elsevier2015