Settling of Particles in Fresh Cement Pastes

Wheeler, J.; Chatterji, S.

doi:10.1111/j.1151-2916.1972.tb11340.x

Cited by 15 publications

(7 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Alternative approaches include those analysing the transmission-attenuation response of laser light in sample based devices such as the Lumizier (from Lum GmbH) and Turbiscan (Formulation, SA) [9][10][11]; however, these ex situ systems are only suitable for small sample analysis of slowly evolving suspensions. In situ devises include light based transmission/backscatter or fluorescence devices [12][13][14][15][16][17][18], CCD video analysis [19][20][21][22][23], gamma ray [24,25] or x-ray CATSCAN [26], and also tomographic techniques which measure electrical resistance within suspensions [27,28]. However, a number of these techniques suffer from common limitations to their use, such complicated set-ups that encompass specific vessel requirements (and hence are not suitable for deployment industrially) while many are highly intrusive, or complex and expensive in application [29].…”

Section: Introductionmentioning

confidence: 99%

In situ characterisation of a concentrated colloidal titanium dioxide settling suspension and associated bed development: Application of an acoustic backscatter system

et al. 2015

View full text Add to dashboard Cite

ReuseUnless indicated otherwise, fulltext items are protected by copyright with all rights reserved. The copyright exception in section 29 of the Copyright, Designs and Patents Act 1988 allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. The publisher or other rights-holder may allow further reproduction and re-use of this version -refer to the White Rose Research Online record for this item. Where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher's website. TakedownIf you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing eprints@whiterose.ac.uk including the URL of the record and the reason for the withdrawal request. eait.dean@uq.edu.au (S.Biggs). T.N.Hunter@leeds.ac.uk (T.N. Hunter).1 Present address: University of Queensland, Brisbane, Qld 4072, Australia 2 AbstractThe ability to accurately characterise the settling of particulate suspensions is imperative in numerous industries for improved processing, optimisation and control. Characterisation is typically a non-trivial process, and in situ measurements that remove the restriction of requiring particular sample sizes are preferred. Here for the first time, we explore the use of an acoustic backscatter system (ABS) to characterise key settling dynamics within a common colloidal mineral suspension, where backscatter attenuation is heightened due to the associated low scattering cross sections of the particles. Settling titanium dioxide dispersions with concentrations ranging 0.05 -3.00 vol% were successfully profiled using ABS transducers of 1, 2 and 4 MHz frequencies. This approach enabled the simultaneous visualisation of both the settling interface and sediment bed formation, generating sedimentation curves and eluding settling velocities. Furthermore, backscatter attenuation was empirically correlated with the attenuation-concentration relationship established for homogenous dispersions, to obtain concentration profiles of the settling suspensions. The data depicted concentration changes as a function of time in a hindered settling suspension, and allowed observation of the segregation of a size polydisperse suspension. Data were compared with sedimentation data obtained via two common ex situ bench-scale techniques. Critically, the acoustic backscatter method was validated as a powerful in situ characterisation tool for opaque concentrated heterogeneous dispersions, with the ability to provide concentration density information in conjunction with settling kinetics that is not easily attainable via other methods.

show abstract

Section: Introductionmentioning

confidence: 99%

In situ characterisation of a concentrated colloidal titanium dioxide settling suspension and associated bed development: Application of an acoustic backscatter system

et al. 2015

View full text Add to dashboard Cite

show abstract

“…The hardened CSD samples were removed from the mold and the open-end of the mold was marked on the samples. This was to observe the influence of slurry sedimentation on the results (Wheeler and Chaterji, 1972). The CSD samples were left to set at room temperature for 20 days.…”

Section: Preparation Of Csd Samplesmentioning

confidence: 99%

The effect of water on the mechanical properties of soluble and insoluble ceramic cements

Koh

López

Pinar

et al. 2015

Journal of the Mechanical Behavior of Biomedical Materials

View full text Add to dashboard Cite

“…Taking this into account, sedimentation induced collisions were not considered. Given the typical settling velocities observed in fresh cement pastes [38,39], the small gap width in this experimental geometry and the time frame the model aims to capture, significant amounts of sedimentation should not occur. Thus, the collision frequency term in Equation (17) adopts the form of the widely known expression for orthokinetic aggregation under laminar shear flow [35,40]:…”

Section: Modelmentioning

confidence: 99%

Numerical Validation of a Population Balance Model Describing Cement Paste Rheology

Gallo-Molina

Lesage

2020

Materials

View full text Add to dashboard Cite

Rheology control is essential during the period in which cement and concrete pastes are encountered in the fresh state, due to the fact that it directly affects workability, initial placement and the structural performance of the hardened material. Optimizations of clinker formulations and reductions in cement-to-water ratios induced by economic and environmental considerations have a significant effect in rheology, which invokes the need for mechanistic models capable of describing the effect of multiple relevant phenomena on the observed paste flow. In this work, the population balance framework was implemented to develop a model able to relate the transient microstructural evolution of cement pastes under typical experimental conditions with its macroscopic rheological responses. Numerical details and performance are assessed and discussed. It was found that the model is capable of reproducing experimentally observed flow curves by using measured cluster size distribution information. It is also able to predict the complex rheological characteristics typically found in cement pastes. Furthermore, a spatially resolved scheme was proposed to investigate the nature of flow inside a parallel-plates rheometer geometry with the objective of assessing the ability of the model of qualitatively predicting experimentally observed behavior and to gain insight into the effect of possible secondary flows.

show abstract

Settling of Particles in Fresh Cement Pastes

Cited by 15 publications

References 4 publications

In situ characterisation of a concentrated colloidal titanium dioxide settling suspension and associated bed development: Application of an acoustic backscatter system

In situ characterisation of a concentrated colloidal titanium dioxide settling suspension and associated bed development: Application of an acoustic backscatter system

The effect of water on the mechanical properties of soluble and insoluble ceramic cements

Numerical Validation of a Population Balance Model Describing Cement Paste Rheology

Contact Info

Product

Resources

About