Journal article
Phase evolution and mechanical performance of an ettringite-based binder during hydrothermal aging
Little is known about the performance of ettringite-based binders in hydrothermal conditions. This investigation aims to gain insights into the phase evolution and corresponding mechanical performance of an ettringite-based binder considering crystallization pressure caused by late-reaction products.
Additionally, the role of fiber reinforcement on the strength retention of the binder was investigated. When aged at an elevated temperature under water-saturated conditions, hard-burned MgO hydrated to form brucite. The precipitation and growth of the brucite crystals led to a crystallization pressure of approximately 200 MPa calculated using thermodynamic modelling.
Damage was observed after 4 months of aging with cracks in the microstructure and eventually a failure at the macro scale. Ettringite remained stable at 60 âŚC due to the water-saturated conditions. Polypropylene fiber delayed crack propagation and thus reduced the damage caused by crystallization pressure.
The fiber improved the flexural performance of composite attaining deflection-hardening behavior regardless of aging conditions.
Language: | English |
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Year: | 2021 |
Pages: | 106403 |
ISSN: | 18733948 and 00088846 |
Types: | Journal article |
DOI: | 10.1016/j.cemconres.2021.106403 |
ORCIDs: | Kunther, Wolfgang |