Zitieren Sie bitte immer diesen URN: urn:nbn:de:kobv:b43-599928
Influence of salt aggregate on the degradation of hybrid alkaline cement (HAC) concretes in magnesium chloride-rich saline solution simulating evaporite rock
- Concretes produced from salt aggregate and hybrid alkaline cements, an alkali-activated slag/fly ash blend, or a Portland cement were exposed to a magnesium chloride-rich saline solution ([Mg2+] = 3.6 m, [Cl−] = 8.3 m), representing a solution formed after contact of surface water with evaporite rock (rock salt) in a nuclear waste repository. The hydration and deterioration of the concretes were studied with X-ray diffraction, thermogravimetric analysis, pH mapping and permeability measurements. The results show that calcium silicate hydrate (C-S-H) or sodium-substituted calcium aluminium silicate hydrate (C-N-A-S-H) and Friedel's salt were the major reaction products in the concretes prior to exposure to the saline solution. During exposure to the saline solution, increasing amounts of C-S-H/C-N-A-S-H dissolved, and gypsum and a secondary AFm phase formed. The durability of the concretes improved with increasing amounts of Portland clinker in the cements, due to the associatedConcretes produced from salt aggregate and hybrid alkaline cements, an alkali-activated slag/fly ash blend, or a Portland cement were exposed to a magnesium chloride-rich saline solution ([Mg2+] = 3.6 m, [Cl−] = 8.3 m), representing a solution formed after contact of surface water with evaporite rock (rock salt) in a nuclear waste repository. The hydration and deterioration of the concretes were studied with X-ray diffraction, thermogravimetric analysis, pH mapping and permeability measurements. The results show that calcium silicate hydrate (C-S-H) or sodium-substituted calcium aluminium silicate hydrate (C-N-A-S-H) and Friedel's salt were the major reaction products in the concretes prior to exposure to the saline solution. During exposure to the saline solution, increasing amounts of C-S-H/C-N-A-S-H dissolved, and gypsum and a secondary AFm phase formed. The durability of the concretes improved with increasing amounts of Portland clinker in the cements, due to the associated differences in permeability and chemical resistance. Nevertheless, a massive increase of permeability occurred for all concretes, likely caused by crack formation due to the formation of gypsum from anhydrite in the salt aggregate. Thus, the behavior of the concretes differed from, and was more complex than, the behavior of plain cement pastes.…
Autor*innen: | Ricky HenningORCiD, Patrick SturmORCiD, S. KeßlerORCiD, Gregor GluthORCiD |
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Persönliche Herausgeber*innen: | B. Lothenbach, E. Wieland, M. Altmaier |
Dokumenttyp: | Zeitschriftenartikel |
Veröffentlichungsform: | Verlagsliteratur |
Sprache: | Englisch |
Titel des übergeordneten Werkes (Englisch): | Applied Geochemistry |
Jahr der Erstveröffentlichung: | 2024 |
Organisationseinheit der BAM: | 7 Bauwerkssicherheit |
7 Bauwerkssicherheit / 7.4 Baustofftechnologie | |
Veröffentlichende Institution: | Bundesanstalt für Materialforschung und -prüfung (BAM) |
Verlag: | Elsevier |
Jahrgang/Band: | 168 |
Aufsatznummer: | 106027 |
Erste Seite: | 1 |
Letzte Seite: | 14 |
DDC-Klassifikation: | Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Angewandte Physik |
Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurbau | |
Freie Schlagwörter: | Concrete; Evaporite rock; Hybrid alkaline cement; Magnesium chloride brine; Nuclear waste repository |
Themenfelder/Aktivitätsfelder der BAM: | Energie |
Energie / Kerntechnische Entsorgung | |
Infrastruktur | |
Infrastruktur / Green Intelligent Building | |
Veranstaltung: | Joint 6th International Workshop on Mechanisms and Modelling of Waste/Cement Interactions (JCCW 2023) |
Veranstaltungsort: | Prague, Czech Republic |
Beginndatum der Veranstaltung: | 20.11.2023 |
Enddatum der Veranstaltung: | 24.11.2023 |
DOI: | 10.1016/j.apgeochem.2024.106027 |
URN: | urn:nbn:de:kobv:b43-599928 |
ISSN: | 0883-2927 |
ISSN: | 1872-9134 |
Verfügbarkeit des Dokuments: | Datei für die Öffentlichkeit verfügbar ("Open Access") |
Lizenz (Deutsch): | Creative Commons - CC BY - Namensnennung 4.0 International |
Datum der Freischaltung: | 06.05.2024 |
Referierte Publikation: | Ja |
Datum der Eintragung als referierte Publikation: | 19.06.2024 |
Schriftenreihen ohne Nummerierung: | Wissenschaftliche Artikel der BAM |