Behaviour of reinforced alkali-activated fly ash mortars under leaching conditions
- Corrosion of steel reinforcement in concrete is one of the major deterioration mechanisms limiting the service life of reinforced concrete structures. While for conventional (Portland cement-based) concretes a great amount of experience exists in this regard, the factors that determine the onset of reinforcement corrosion in alkali-activated materials are incompletely understood yet. One aspect of corrosion protection is leaching and the accompanying changes of the concrete pore solution. In the present study, alkali-activated fly ash mortars with embedded carbon steel rebars were exposed to de-ionised water for periods up to 330 days, and the electrochemical response of the steel (free corrosion potential, polarisation resistance), the alteration of the mortar (ohmic resistance, mechanical strength, pore size distribution) as well as the pore solution composition were monitored. Although substantial alkali leaching was observed, the pH of the pore solution remained at valuesCorrosion of steel reinforcement in concrete is one of the major deterioration mechanisms limiting the service life of reinforced concrete structures. While for conventional (Portland cement-based) concretes a great amount of experience exists in this regard, the factors that determine the onset of reinforcement corrosion in alkali-activated materials are incompletely understood yet. One aspect of corrosion protection is leaching and the accompanying changes of the concrete pore solution. In the present study, alkali-activated fly ash mortars with embedded carbon steel rebars were exposed to de-ionised water for periods up to 330 days, and the electrochemical response of the steel (free corrosion potential, polarisation resistance), the alteration of the mortar (ohmic resistance, mechanical strength, pore size distribution) as well as the pore solution composition were monitored. Although substantial alkali leaching was observed, the pH of the pore solution remained at values sufficient to protect the embedded steel from depassivation. The mortar did not exhibit indications of significant deterioration. Thus, the present results suggest that leaching is not critical for protection of steel reinforcement in alkali-activated fly ash mortars and concretes.…
Autor*innen: | Petr Hlavacek, Steffi Reinemann, Gregor GluthORCiD, Gino EbellORCiD, Jürgen Mietz |
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Persönliche Herausgeber*innen: | M. Serdar, N. Stirmer, J. Provis |
Dokumenttyp: | Beitrag zu einem Tagungsband |
Veröffentlichungsform: | Verlagsliteratur |
Sprache: | Englisch |
Titel des übergeordneten Werkes (Englisch): | Proceedings of the International Conference on Sustainable Materials, Systems and Structures (SMSS2019), Vol. 1: New Generation of Construction Materials |
Jahr der Erstveröffentlichung: | 2019 |
Organisationseinheit der BAM: | 7 Bauwerkssicherheit |
7 Bauwerkssicherheit / 7.4 Baustofftechnologie | |
7 Bauwerkssicherheit / 7.6 Korrosion und Korrosionsschutz | |
Verlag: | RILEM Publications |
Verlagsort: | Paris |
Jahrgang/Band: | 1 |
Erste Seite: | 118 |
Letzte Seite: | 124 |
DDC-Klassifikation: | Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurbau |
Freie Schlagwörter: | Alkali-activated materials; Leaching; Steel corrosion |
Themenfelder/Aktivitätsfelder der BAM: | Infrastruktur |
Veranstaltung: | International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) |
Veranstaltungsort: | Rovinj, Croatia |
Beginndatum der Veranstaltung: | 20.03.2019 |
Enddatum der Veranstaltung: | 22.03.2019 |
ISBN: | 978-2-35158-223-7 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 20.03.2019 |
Referierte Publikation: | Nein |