Publications associées à Impact of the microstructure model on coupled simulation of drying and accelerated carbonation

Contradict mechanism of long-term magnesium and sodium sulfate attacks of nano silica-modified cement mortars - Experimental and thermodynamic modeling

The mechanisms of external sulfate attack on cement mortars containing nano silica have been studied under full immersion conditions after 3 years. The sulfate degradation processes were compared between sodium sulfate and magnesium sulfate solutions with ...

Elsevier Sci Ltd2024

The role of Zn in C-S-H atomic structure, nucleation and growth

Anna Morales Melgares

The most promising solution towards cementitious materials with a lower carbon footprint is the partial substitution of the clinker by supplementary cementitious materials (SCMs) such as fly ash, blast furnace slag, limestone and calcined clays. The produc ...

EPFL2023

Going Below 50% Clinker Factor in Limestone Calcined Clay Cements (LC3): A Comparison with Pozzolanic Cements from the South American Market

Karen Scrivener, Franco Alberto Zunino Sommariva

Limestone calcined clays are a promising technology as they offer similar performance to OPC from 7 days onwards, while enabling a reduction of the clinker content of 50%. In some regions of the world like South America, pozzolanic cements (i.e., blended c ...

SPRINGER INTERNATIONAL PUBLISHING AG2023

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

Karen Scrivener, Matea Flegar

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

Impact of chlorination and ozonation of dissolved organic matter on its photo-induced production of long-lived photooxidants and excited triplet states

Silvio Canonica, Urs von Gunten, Stephanie Christa Remke, Joanna Maria Houska

Recent studies suggested that long-lived photooxidants (LLPO), which are reactive intermediates formed during irradiation of dissolved organic matter (DOM), may consist of phenoxyl radicals derived from phenolic moieties of the DOM. Besides the well-studie ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Unidirectional penetration approach for characterizing sulfate attack mechanisms on cement mortars and pastes

Karen Scrivener, Qiao Wang, William Wilson

Degradation of cementitious materials by sulfate ions is commonly classified into chemical and physical sulfate attack. So-called "physical" attack dominates in many field situations, but laboratory testing focuses on "chemical" attack under full-immersion ...

Pergamon-Elsevier Science Ltd2023

Towards Uncovering the Mechanisms of Electrophile Sensing and Signaling

Chloé Rogg

Native reactive electrophile species (RES) such as 4-hydroxynonenal (HNE) act as cellular signals through covalent modification of kinetically-privileged electrophile sensor proteins. Research efforts in the field focus mainly on identifying these sensor p ...

EPFL2023

Large Orbital Moment of Two Coupled Spin-Half Co Ions in a Complex on Gold

Stefano Rusponi, Chao Li, Boris Sorokin

The magnetic propertiesof transition-metal ions aregenerallydescribed by the atomic spins of the ions and their exchange coupling.The orbital moment, usually largely quenched due the ligand field,is then seen as a perturbation. In such a scheme, S = 1/2 io ...

AMER CHEMICAL SOC2023

Mechanical Properties and Nanomotion of BT-20 and ZR-75 Breast Cancer Cells Studied by Atomic Force Microscopy and Optical Nanomotion Detection Method

Sandor Kasas, María Inés Villalba

Cells of two molecular genetic types of breast cancer-hormone-dependent breast cancer (ZR-75 cell line) and triple-negative breast cancer (BT-20 cell line)-were studied using atomic force microscopy and an optical nanomotion detection method. Using the Pea ...

MDPI2023

Interventionist estimands in event history analysis

Matias Janvin

The presence of competing events, such as death, makes it challenging to define causal effects on recurrent outcomes. In this thesis, I formalize causal inference for recurrent events, with and without competing events. I define several causal estimands an ...

EPFL2023

Non-volatile data storage medium and system

Martin Vetterli, Yves Bellouard, Ruben Ricca

A data storage medium (2) comprising a stacked plurality of layers (9), each layer composed of a layer material selected from a group comprising at least two different dielectric materials, adjacent layers being formed of different materials, and at least ...

2023

Resistance of cementitious materials to sulfate attack: quantifying performance with a reliable unidirectional approach

Qiao Wang

Depending on the environmental conditions, concrete materials can come into contact with sulfate ions which are widely present in rivers, underground water, sewers, seawater and soil. Sulfates can react with the cement paste in concrete and cause damage wh ...

EPFL2022

Nanoscale modelling of ionic transport in the porous C-S-H network

Khalil Ferjaoui

To reduce the CO2 footprint of construction materials, concrete producers blend their cement with Supplementary Cementitious Materials (SCMs). SCMs such as fly ash or blast furnace slag are mostly the byproducts of other industries. And while SCMs are chos ...

EPFL2022

The effect of pore microstructure on strength and chloride ingress in blended cement based on low kaolin clay

Karen Scrivener, Diana Londoño Zuluaga

The objective of this study is to analyse the mechanical and durability properties of a high-performance mortars based on low grade kaolin clay and the effect of electrical conductivity and pore microstructure on the chloride penetration resistance. A tota ...

ELSEVIER2022

The Challenge of Grinding Ternary Blends Containing Calcined Clays and Limestone

Karen Scrivener, Franco Alberto Zunino Sommariva, Juan Alberto Ribalta Quesada

The inclusion of high specific surface materials such as calcined clays in cementitious systems enhances the hydration of clinker products at very early ages, but it may also increase water demand; thus, the pursuit of a flowing concrete may demand an incr ...

MDPI2022

Reactive dicalcium silicate binders: Microstructure and transport properties

Adrian-Alexandru Pîrvan

The calcium silicate hydrates (C-S-H) are without doubt one of the most important hydration products in a hardened cement paste. Giving the complexity of the microstructure that forms by hydration of ordinary Portland cement (OPC) and the more recently use ...

EPFL2022

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

Hydration and durability of fast hardening binders incorporating supplementary cementitious materials

Sarra El Housseini

The use of supplementary cementitious materials (SCMs) is widely considered the most promis-ing approach to reduce CO2 emissions relative to cement production. SCMs are not commonly present in binders used for special applications. On the other hand, due t ...

EPFL2022

Microstructural developments of limestone calcined clay cement (LC3) pastes after long-term (3 years) hydration

Karen Scrivener, Franco Alberto Zunino Sommariva

LC3 is one of the most promising alternatives for a high-performance blended cement with a significantly lower clinker content and with potential for worldwide adoption. For this reason, understanding its long-term performance is relevant to ensure service ...

Pergamon-Elsevier Science Ltd2022

Atomistic Simulation of Cementitious Systems: An Insight Into Adsorption of Ions and Small Molecules Onto Portlandite and C-S-H Surfaces

Masood Valavi

Calcium-Silicate-Hydrate (C-S-H) has been studied extensively over the last few decades to gain understanding toward the underlying mechanism of different stages during cement hydration. The variable stoichiometry and nanocrystallinity of C-S-H makes it di ...

EPFL2022