Abstract
A promising solution for reducing the carbon footprint of concrete is the use of alkali-activated concretes (AAC). Before this material can be widely applied, its long-term behaviour needs to be understood, especially since some studies reported a decrease of mechanical properties over time. Similarly, Prinsse et al. reported decreasing mechanical properties, especially elastic modulus and flexural and splitting tensile strength for the studied slag-based AAC (S100) and the blended slag- and fly-ash-based AAC (S50) up to the tested age of 2 years. They hypothesized that these decreases could be only temporarily. To test that hypothesis, this study continued to monitor the mechanical properties of both AACs up to the age of 5 years. As a reference, two OPC-based concretes (OPCC), with different strength classes, are monitored up to the age of 3.5 years. In addition, the internal structures of the concretes are assessed for carbonation and internal micro cracking. S100 shows stabilization of the elastic modulus and the compressive strength, whereas the tensile splitting strength continued to decrease up to 5 years. This is attributed to a combination of carbonation and drying, since the microscopic analysis showed increased porosity around the ITZ and in the carbonated region. In addition, S50 shows an ongoing decrease of all tested mechanical properties, which is attributed to carbonation. No decreases in mechanical properties are found for OPCC.
Original language | English |
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Title of host publication | International RILEM Conference on Synergising Expertise towards Sustainability and Robustness of Cement-based Materials and Concrete Structures |
Subtitle of host publication | SynerCrete’23 - Volume 2 |
Publisher | Springer |
Pages | 462–472 |
Number of pages | 11 |
Volume | 44 |
ISBN (Electronic) | 978-3-031-33187-9 |
ISBN (Print) | 978-3-031-33186-2, 978-3-031-33189-3 |
DOIs | |
Publication status | Published - 2023 |
Event | SynerCrete 2023 - The Milos Conference Center – George Eliopoulos, Adamantas, Greece Duration: 14 Jun 2023 → 15 Jun 2023 https://synercrete.com/ |
Publication series
Name | RILEM Bookseries |
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Volume | 44 |
ISSN (Print) | 2211-0844 |
ISSN (Electronic) | 2211-0852 |
Conference
Conference | SynerCrete 2023 |
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Country/Territory | Greece |
City | Adamantas |
Period | 14/06/23 → 15/06/23 |
Internet address |
Bibliographical note
Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-careOtherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.
Keywords
- Alkali Activated Concrete
- Time-dependent Behaviour
- Alkali Activated Slag
- Drying
- Durability
- Carbonation