Autogenous self-healing of thermally damaged cement paste with carbon nanomaterials subjected to different environmental stimulators
Artykuł w czasopiśmie
MNiSW
140
Lista 2023
| Status: | |
| Autorzy: | Rajczakowska Magdalena, Szeląg Maciej, Habermehl-Cwirzen Karin, Hedlund Hans, Cwirzen Andrzej |
| Dyscypliny: | |
| Aby zobaczyć szczegóły należy się zalogować. | |
| Rok wydania: | 2023 |
| Wersja dokumentu: | Drukowana | Elektroniczna |
| Język: | angielski |
| Wolumen/Tom: | 72 |
| Numer artykułu: | 106619 |
| Strony: | 1 - 22 |
| Web of Science® Times Cited: | 3 |
| Scopus® Cytowania: | 3 |
| Bazy: | Web of Science | Scopus | Ei Compendex; INSPEC |
| Efekt badań statutowych | NIE |
| Finansowanie: | The project has received support from the Swedish Transport Administration (Trafikverket) and the Development Fund of the Swedish Construction Industry (SBUF). |
| Materiał konferencyjny: | NIE |
| Publikacja OA: | TAK |
| Licencja: | |
| Sposób udostępnienia: | Witryna wydawcy |
| Wersja tekstu: | Ostateczna wersja opublikowana |
| Czas opublikowania: | W momencie opublikowania |
| Data opublikowania w OA: | 30 kwietnia 2023 |
| Abstrakty: | angielski |
| Autogenous self-healing of post-fire damaged concrete enables structure performance auto- recovery leading to reduced repair costs, less generated waste, and lower CO2 emissions. In this paper, to improve the efficiency of this process and understand the underlying mechanism, the self-healing of 0.1 wt% MWCNT-modified and pure cement paste subjected to novel envi- ronmental stimulators was tested. High-temperature damage was induced at 200 ◦C and 400 ◦C, followed by a self-healing cyclic treatment with water, a mixture of water with phosphate-based retarding admixture, and limewater. The self-healing efficiency of the proposed solutions were compared based on crack closure, strength regains, porosity, and chemical composition changes. The surface crack closure after 200 ◦C varied between 33% and 60%, whereas for 400 ◦C, only retarding admixture exposure obtained over 50% crack closure and the most considerable decrease in average crack width of 33% for MWCNT-modified paste. The highest values of compressive strength recovery, equal to 18% and 14%, exceeding the intact specimen’s compressive strength, were observed for the MWCNT-modified paste healed in water and lime- water. Water exposure with an extended wetting phase enhanced the compressive strength re- covery of the MWCNT-modified materials. Strong (r = 0.87) and moderate (r = 0.52) positive correlations were observed between temperature loading and compressive and flexural strength recovery parameters, respectively. Higher porosity and interconnected crack network, caused by high temperature, facilitated the self-healing process. Porosity changes before and after healing were pronounced in contrast to the amount of unhydrated cement, which did not exhibit noticeable changes. The healing mechanism included three processes: calcite formation, further hydration inside the cracks, and rehydration of the bulk cement paste. |
