Alite-ye'elimite clinker: Hydration kinetics, products and microstructure

Xuerun Li, Karen Scrivener, Ruben Anton Snellings
ELSEVIER SCI LTD, 2021
Journal paper

This paper presents the hydration kinetics, products and microstructure of an alite-ye'elimite clinker containing 4 wt% of ye'elimite to boost the early strength development. Isothermal calorimetry, X-ray diffraction, backscattered scanning electron microscopy and mercury intrusion porosimetry were used to study the hydration processes. The results showed that the ye'elimite phase hydrated very rapidly, before the main hydration of alite, forming ettringite as main hydration product. The ye'elimite hydration products precipitated throughout the pore space and reduced the microporosity of the hardened paste at early age. The presence of ye'elimite strongly affected the early hydration before 24 h of hydration, but did not show a significant effect on the hydration kinetics or products at later ages. (C) 2020 Elsevier Ltd. All rights reserved.

About this result

This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.

Related concepts

Related publications

Xuerun Li, Karen Scrivener, Ruben Anton Snellings
ELSEVIER SCI LTD, 2021
Journal paper

Abstract

Official source

https://infoscience.epfl.ch/record/284279?ln=en

About this result

Related concepts (9)

Related concepts

Related publications (33)

Related publications

Hydrate

In chemistry, a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labe

Scanning electron microscope

A scanning electron microscope (SEM) is a type of electron microscope that produces images of a sample by scanning the surface with a focused beam of electrons. The electrons interact with atoms

Differential scanning calorimetry

Differential scanning calorimetry (DSC) is a thermoanalytical technique in which the difference in the amount of heat required to increase the temperature of a sample and reference is measured as a fu

Impact of Annealing on the Early Hydration of Tricalcium Silicate

Amélie Bazzoni, Marco Cantoni, Karen Scrivener

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 annealing effects on the defect structure and hydration behavior of C3S. The impact of annealing on the crystal structure was checked by X-ray diffraction and the defect structure studied by transmission electron microscopy. The hydration kinetics were followed by isothermal calorimetry of pastes. Scanning electron microscopy was used to look at the microstructure formation. It was observed that grinding created a highly deformed layer on the surface of the grains, which disappeared after annealing. The defect structure was closely related to the length of the induction period observed in pastes by calorimetry. There was no observable effect on the morphology of C-S-H during hydration, but the number of calcium hydroxide nuclei was less in pastes from annealed material.

Wiley-Blackwell2014

Effect of cement substitution by limestone on the hydration and microstructural development of ultra-high performance concrete (UHPC)

Wei Huang, Karen Scrivener, Wei Sun

The effect of limestone on the hydration and microstructural development of ultra high performance concrete (UHPC) with different levels of replacement (34%, 54% and 74% by volume) was investigated. Up to 54% replacement of cement by limestone the mixes showed better workability and higher compressive strength (170 MPa at 56 days for 54% addition) compared to a classical mix (155 MPa) with no limestone replacement. The kinetics of hydration were compared for different replacement levels using isothermal calorimetry. The phase development was quantified by X-ray diffraction with Rietveld method combined with thermal gravimetric analysis. The pore structure was examined by mercury intrusion porosimetry. The composition of hydration products was determined by scanning electron microscopy with energy dispersive X-ray analysis. The results showed that the hydration degree of the cement is increased from 39% for classical UHPC to 66% for the UHPC with 54% of limestone. (C) 2016 Elsevier Ltd. All rights reserved.

Elsevier2017

Hydration of C(3)A-gypsum systems

Alexandra Quennoz, Karen Scrivener

Hydration of C(3)A-gypsum systems with different gypsum additions was investigated in terms of the phase assemblage, kinetics and microstructural development. The second stage of the reaction, which begins after the depletion of gypsum, was of particular interest. From in-situ X-ray diffraction results, it was seen that the dissolution of ettringite and C(3)A to form monosulfoaluminate and/or hydroxy-AFm phases is a rapid reaction that occurs right after the depletion of gypsum. The observation of the calorimetric curves obtained for the different gypsum additions leads us to the conclusion that the mechanism controlling the hydration rate during this period is the nucleation and growth of the AFm phases. The microstructural study showed that the formation of AFm phases occurs in the space between the C(3)A grains but also within the boundaries of the original C(3)A grains. Hydrogarnet was observed growing as a shell around the C(3)A grains. (C) 2012 Elsevier Ltd. All rights reserved.

2012