Influence of effects on nano and micro scale on the rheological performance of cement paste, mortar and concrete
- Chemical admixtures like superplasticisers or stabilising agents are of ever increasing importance for modern concrete technology. They liberate the workability of concrete from its dependency on water content, and thus, open the gate towards innovative and future oriented concrete technologies such as self-compacting concrete. Today, admixture addition has become common practice in concrete technology, but the understanding of their highly complex mode of operation is extremely difficult and demands for understanding of processes within the range between nanometres and centimetres. Due to its complex time-dependent, multi-phase and multi-scale behaviour, flowable concrete systems are highly complicated and cannot be described comprehensively by simple models. It is therefore extremely challenging to identify the relevant parameters that predominantly control flow phenomena on different size scales, since these may occur on any scale between the nano scale (e.g. superplasticizerChemical admixtures like superplasticisers or stabilising agents are of ever increasing importance for modern concrete technology. They liberate the workability of concrete from its dependency on water content, and thus, open the gate towards innovative and future oriented concrete technologies such as self-compacting concrete. Today, admixture addition has become common practice in concrete technology, but the understanding of their highly complex mode of operation is extremely difficult and demands for understanding of processes within the range between nanometres and centimetres. Due to its complex time-dependent, multi-phase and multi-scale behaviour, flowable concrete systems are highly complicated and cannot be described comprehensively by simple models. It is therefore extremely challenging to identify the relevant parameters that predominantly control flow phenomena on different size scales, since these may occur on any scale between the nano scale (e.g. superplasticizer adsorption) and macro scale (e.g. grading of the aggregates). The present study discusses fundamental mechanisms at the interface between particle or hydrate surfaces and the fluid phase at a very early stage of concrete formation, and links these effects to macroscopic flow phenomena. Methods are discussed that appear promising interdisciplinary tools for enhancement of the understanding of the relevant interactions that are responsible for the macroscopic flow of flowable concrete.…
Autor*innen: | Wolfram SchmidtORCiD, Berta Mota Gassó, Heinz SturmORCiD, Jutta Pauli |
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Persönliche Herausgeber*innen: | M. Greim, W. Kusterle, O. Teubert |
Dokumenttyp: | Beitrag zu einem Tagungsband |
Veröffentlichungsform: | Verlagsliteratur |
Sprache: | Englisch |
Titel des übergeordneten Werkes (Deutsch): | Rheologische Messungen an Baustoffen |
Jahr der Erstveröffentlichung: | 2016 |
Verlag: | tredition |
Verlagsort: | Hamburg |
Erste Seite: | 294 |
Letzte Seite: | 307 |
DDC-Klassifikation: | Naturwissenschaften und Mathematik / Chemie / Analytische Chemie |
Freie Schlagwörter: | Cement; Concrete; Nano scale; Rheology; Superplasticizer |
Veranstaltung: | 25. Workshop und Kolloquium Rheologische Messsungen an Baustoffen |
Veranstaltungsort: | Regensburg, Germany |
Beginndatum der Veranstaltung: | 02.03.2016 |
Enddatum der Veranstaltung: | 03.03.2016 |
ISBN: | 978-3-7345-1313-8 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 15.07.2016 |
Referierte Publikation: | Nein |