Effects of particle volume fraction and size on polysaccharide stabilizing agents
- Polysaccharides modify the rheological properties of cement based systems. Depending upon their chemistry, molecular architecture, and adsorption tendency, they have different modes of action. Some polysaccharides like diutan gum have strong effect on the fluid phase; others like starch strongly interact with particles. This paper presents effects of diutan gum and starches in presence of polycarboxylates. Rheometric investigations with varied particle volume fractions and increasing coarse aggregate diameters were conducted. The results show that starches have stronger influence on the rheology at high particle volume fractions than diutan gum. At lower particle volume fractions this trend is inverted. Experiments with aggregates sizes up to 16 mm (0.63 in.) indicate that stabilizing agent influences on the effects of aggregates on yield stress were small; however up to 1.0 mm (0.04 in.), a significant effect on the plastic viscosity could be observed, which levelled off at largerPolysaccharides modify the rheological properties of cement based systems. Depending upon their chemistry, molecular architecture, and adsorption tendency, they have different modes of action. Some polysaccharides like diutan gum have strong effect on the fluid phase; others like starch strongly interact with particles. This paper presents effects of diutan gum and starches in presence of polycarboxylates. Rheometric investigations with varied particle volume fractions and increasing coarse aggregate diameters were conducted. The results show that starches have stronger influence on the rheology at high particle volume fractions than diutan gum. At lower particle volume fractions this trend is inverted. Experiments with aggregates sizes up to 16 mm (0.63 in.) indicate that stabilizing agent influences on the effects of aggregates on yield stress were small; however up to 1.0 mm (0.04 in.), a significant effect on the plastic viscosity could be observed, which levelled off at larger diameters.…
Autor*innen: | Wolfram SchmidtORCiD, Sarah Leinitz, Hans-Carsten KühneORCiD |
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Persönliche Herausgeber*innen: | V. M. Malhotra, P. R. Gupta, T. C. Holland |
Dokumenttyp: | Beitrag zu einem Tagungsband |
Veröffentlichungsform: | Verlagsliteratur |
Sprache: | Englisch |
Titel des übergeordneten Werkes (Englisch): | 11th International Conference on Superplasticizers and Other Chemical Admixtures in Concrete |
Jahr der Erstveröffentlichung: | 2015 |
Herausgeber (Institution): | ACI |
Erste Seite: | SP-302-03, 39 |
Letzte Seite: | 52 |
DDC-Klassifikation: | Naturwissenschaften und Mathematik / Chemie / Analytische Chemie |
Freie Schlagwörter: | Diutan gum; Polycarboxylate ether; Polysaccharides; Starch; Volume fraction |
Veranstaltung: | 11th International Conference on Superplasticizers and Other Chemical Admixtures in Concrete |
Veranstaltungsort: | Ottawa, Canada |
Beginndatum der Veranstaltung: | 12.07.2015 |
Enddatum der Veranstaltung: | 15.07.2015 |
ISBN: | 9781942727224 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 19.07.2016 |
Referierte Publikation: | Nein |