Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Hydration of blended cement with high volume iron-rich slag from non-ferrous metallurgy
Abstract The hydration of blended cements with up to 70 wt% iron-rich slag was investigated. Isothermal calorimetry revealed a retarding effect of the slag on Portland cement hydration during the first day, while from 2 days onwards the reaction extent of C3S, C3A and C4AF increased. The slag reacted to 20–30% after 150 days resulting in AFm phases, as well as a new phase with a layered double hydroxide structure with (Mg + Fe)/Al around 3. Fe was also detected in the C-S-H phase of the blended cements, whereas no clear increase of Fe(III)-containing hydrates was observed. The Ca/Si atomic ratio of C-(A)-S-H in the blended cements decreased with increasing slag content, while the Al/Ca ratio increased only slightly. This study elucidated the fate of iron in cements blended with iron-rich slags and showed the suitability of the latter as SCM with a reactivity similar to the one of siliceous fly ash.
Highlights Non-ferrous metallurgy (NFM) slag in cement reacts up to 20–30% after 150 days. Clinker hydration degree increases in blended cements with NFM slag. The fate of Fe in blended cements with Fe-rich NFM slag is elucidated. (Mg, Fe, Al)-layered double hydroxide is observed in blended cements with NFM slag. Fe is present in the C-(A)-S-H phase of blended cements with NFM slag.
Hydration of blended cement with high volume iron-rich slag from non-ferrous metallurgy
Abstract The hydration of blended cements with up to 70 wt% iron-rich slag was investigated. Isothermal calorimetry revealed a retarding effect of the slag on Portland cement hydration during the first day, while from 2 days onwards the reaction extent of C3S, C3A and C4AF increased. The slag reacted to 20–30% after 150 days resulting in AFm phases, as well as a new phase with a layered double hydroxide structure with (Mg + Fe)/Al around 3. Fe was also detected in the C-S-H phase of the blended cements, whereas no clear increase of Fe(III)-containing hydrates was observed. The Ca/Si atomic ratio of C-(A)-S-H in the blended cements decreased with increasing slag content, while the Al/Ca ratio increased only slightly. This study elucidated the fate of iron in cements blended with iron-rich slags and showed the suitability of the latter as SCM with a reactivity similar to the one of siliceous fly ash.
Highlights Non-ferrous metallurgy (NFM) slag in cement reacts up to 20–30% after 150 days. Clinker hydration degree increases in blended cements with NFM slag. The fate of Fe in blended cements with Fe-rich NFM slag is elucidated. (Mg, Fe, Al)-layered double hydroxide is observed in blended cements with NFM slag. Fe is present in the C-(A)-S-H phase of blended cements with NFM slag.
Hydration of blended cement with high volume iron-rich slag from non-ferrous metallurgy
Hallet, Vincent (Autor:in) / Pedersen, Malene Thostrup (Autor:in) / Lothenbach, Barbara (Autor:in) / Winnefeld, Frank (Autor:in) / De Belie, Nele (Autor:in) / Pontikes, Yiannis (Autor:in)
28.09.2021
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch
A Benchmarking of Slag Blended Cement Hydration Models
| Springer Verlag | 2023
Hydration characteristics of slag-blended cement at different temperatures
| Taylor & Francis Verlag | 2015