Influence of different accelerators on the rheology and early hydration of cement paste
- Special applications like pumping, spraying or printing of concrete require the precise adjustment of very specific rheological properties at different time steps during the casting process. Superplasticizers such as polycarboxylate ethers (PCE) can be used to obtain the required flowability, which, possibly in combination with additional rheology modifying admixtures, generate the required specified consistency. However, after the application, the concrete should change the rheological properties immediately in order to avoid deformations at rest. Therefore, the use of accelerators can be effective. Accelerators influence the hydration of cementitious materials, and thus the rheological properties over the course of time and the setting. In this paper, the influence of different accelerators on the rheology and early hydration of cement paste as well as the interaction of accelerator and PCE are presented. Methods like rheometry, needle penetration tests and practical Tests likeSpecial applications like pumping, spraying or printing of concrete require the precise adjustment of very specific rheological properties at different time steps during the casting process. Superplasticizers such as polycarboxylate ethers (PCE) can be used to obtain the required flowability, which, possibly in combination with additional rheology modifying admixtures, generate the required specified consistency. However, after the application, the concrete should change the rheological properties immediately in order to avoid deformations at rest. Therefore, the use of accelerators can be effective. Accelerators influence the hydration of cementitious materials, and thus the rheological properties over the course of time and the setting. In this paper, the influence of different accelerators on the rheology and early hydration of cement paste as well as the interaction of accelerator and PCE are presented. Methods like rheometry, needle penetration tests and practical Tests like spread flow were applied. The used accelerators showed accelerating behavior on the cement pastes without and in the presence of PCE. At the same time an influence on the rheology could be observed. This effect was less in the mixes with PCE, especially at the highest water/cement ratio (w/c).…
Autor*innen: | Sarah Leinitz, Z. Lu, S. Becker, D. Stephan, R. von Klitzing, Wolfram SchmidtORCiD |
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Persönliche Herausgeber*innen: | V. Mechtcherine, K. Khayat, E. Secrieru |
Dokumenttyp: | Buchkapitel |
Veröffentlichungsform: | Verlagsliteratur |
Sprache: | Englisch |
Titel des übergeordneten Werkes (Englisch): | Rheology and Processing of Construction Materials |
Auflage: | 1 |
Jahr der Erstveröffentlichung: | 2019 |
Organisationseinheit der BAM: | 7 Bauwerkssicherheit |
7 Bauwerkssicherheit / 7.4 Baustofftechnologie | |
Herausgeber (Institution): | RILEM Bookseries |
Verlag: | Springer |
Jahrgang/Band: | 23 |
Erste Seite: | 106 |
Letzte Seite: | 115 |
DDC-Klassifikation: | Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurwissenschaften und zugeordnete Tätigkeiten |
Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurbau | |
Freie Schlagwörter: | Accelerator; Cement paste; Rheology; Setting; Superplasticizer |
Themenfelder/Aktivitätsfelder der BAM: | Infrastruktur |
Material | |
DOI: | 10.1007/978-3-030-22566-7 |
ISSN: | 2211-0844 |
ISBN: | 978-3-030-22565-0 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 30.09.2019 |
Referierte Publikation: | Nein |