<div class="csl-bib-body">
<div class="csl-entry">Kabashi, V. (2022). <i>Pumping of concrete</i> [Diploma Thesis, Technische Universität Wien]. reposiTUm. https://doi.org/10.34726/hss.2022.64283</div>
</div>
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dc.identifier.uri
https://doi.org/10.34726/hss.2022.64283
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dc.identifier.uri
http://hdl.handle.net/20.500.12708/19420
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dc.description.abstract
We show here that pumping mortars over long distances can lead to microstructural heterogeneities. This work follows numerous works on particle migration in ideal (Newtonian) fluids, where particles migrate from areas with higher shear rates (near the wall) to areas with lower shear rate (center of the pipe). We investigated here if migration of particles (sand, aggregates) in cement slurries may also occur as the result of shear induced migration. Looking at the work of Nott and Brady (1994), we calculated that the distance needed to reach steady-state in our mortars would be on the orders of 100s of meters (their theoretical model estimates that the distance depends on the pipe diameter and the particle diameter). Avoiding this difficult experimental challenge, and following the work of Butler, Majors & Bonnecaze (1999) and Snook, Butler & Guazzelli (2015), we built an oscillatory setup. We performed seven experiments with three different mixtures, where the yield stress and cover distance vary. Because we could not measure particle concentration in-situ during flow, we let the mortar set and measured solid volume fractions in various cut and polished sections of the pipe. Each image was treated with ImageJ where we analyzed local particle concentration. For optimal image treatment, we used red particles and white cement. Quantification of the wall steric hindrance, as well as the stability (lack of settling of particles) of all three mixtures were controlled in reference samples (tube of same diameter of pumping pipe, but where no pumping was imposed). In almost all cases, particle migration is clearly evidenced, with a dependence on the cement yield stress.
en
dc.language
English
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dc.language.iso
en
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dc.rights.uri
http://rightsstatements.org/vocab/InC/1.0/
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dc.subject
Beton
de
dc.subject
pumpen
de
dc.subject
concrete
en
dc.subject
pumping
en
dc.title
Pumping of concrete
en
dc.title.alternative
Pumpen von Beton
de
dc.type
Thesis
en
dc.type
Hochschulschrift
de
dc.rights.license
In Copyright
en
dc.rights.license
Urheberrechtsschutz
de
dc.identifier.doi
10.34726/hss.2022.64283
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dc.contributor.affiliation
TU Wien, Österreich
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dc.rights.holder
Valmir Kabashi
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dc.publisher.place
Wien
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tuw.version
vor
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tuw.thesisinformation
Technische Universität Wien
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dc.contributor.assistant
Liberto, Teresa
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tuw.publication.orgunit
E207 - Institut für Werkstofftechnologie, Bauphysik und Bauökologie
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dc.type.qualificationlevel
Diploma
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dc.identifier.libraryid
AC16428266
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dc.description.numberOfPages
73
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dc.thesistype
Diplomarbeit
de
dc.thesistype
Diploma Thesis
en
dc.rights.identifier
In Copyright
en
dc.rights.identifier
Urheberrechtsschutz
de
tuw.advisor.staffStatus
staff
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tuw.assistant.staffStatus
staff
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tuw.assistant.orcid
0000-0002-4985-9110
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item.languageiso639-1
en
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item.mimetype
application/pdf
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item.openairecristype
http://purl.org/coar/resource_type/c_bdcc
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item.fulltext
with Fulltext
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item.openairetype
master thesis
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item.grantfulltext
open
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item.openaccessfulltext
Open Access
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item.cerifentitytype
Publications
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crisitem.author.dept
E207 - Institut für Werkstofftechnologie, Bauphysik und Bauökologie