Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Sulfate resistance of calcined clay – Limestone – Portland cements
https://orcid.org/0000-0003-0000-6560
https://orcid.org/0000-0003-4885-2395
Abstract Calcined clays emerge as a promising source of supplementary cementitious material, which can provide a significant lowering of the Portland clinker content in blended cements. This study focusses on sulfate resistance of calcined clay (CC) – limestone (L) – Portland cements for mortars exposed to a 0.11 M Na2SO4 solution at 5 and 20 °C after a hydration period of 91 days. The pozzolanicity, compressive strength, pore structure, and sulfate resistance of mortars containing laboratory-made metakaolin or calcined montmorillonite and limestone have been investigated in cements with 35 wt% replacement of a white Portland or an ordinary Portland clinker. The results show that all mortars with CC/(CC + L) ≥ 0.5 exhibit excellent sulfate resistance. The consumption of portlandite by the pozzolanic reactions of the calcined clays and the dilution of the Portland clinker lead to a lower amount of calcium available for the secondary formation of gypsum and ettringite, which is identified as the main reason for the excellent sulfate resistance of the ternary blends. The results suggest that calcined clay – limestone – Portland cements are included in standards as a new type of sulfate-resisting Portland pozzolana cement and Portland composite cement.
Sulfate resistance of calcined clay – Limestone – Portland cements
https://orcid.org/0000-0003-0000-6560
https://orcid.org/0000-0003-4885-2395
Abstract Calcined clays emerge as a promising source of supplementary cementitious material, which can provide a significant lowering of the Portland clinker content in blended cements. This study focusses on sulfate resistance of calcined clay (CC) – limestone (L) – Portland cements for mortars exposed to a 0.11 M Na2SO4 solution at 5 and 20 °C after a hydration period of 91 days. The pozzolanicity, compressive strength, pore structure, and sulfate resistance of mortars containing laboratory-made metakaolin or calcined montmorillonite and limestone have been investigated in cements with 35 wt% replacement of a white Portland or an ordinary Portland clinker. The results show that all mortars with CC/(CC + L) ≥ 0.5 exhibit excellent sulfate resistance. The consumption of portlandite by the pozzolanic reactions of the calcined clays and the dilution of the Portland clinker lead to a lower amount of calcium available for the secondary formation of gypsum and ettringite, which is identified as the main reason for the excellent sulfate resistance of the ternary blends. The results suggest that calcined clay – limestone – Portland cements are included in standards as a new type of sulfate-resisting Portland pozzolana cement and Portland composite cement.
Sulfate resistance of calcined clay – Limestone – Portland cements
https://orcid.org/0000-0003-0000-6560
https://orcid.org/0000-0003-4885-2395
Abstract Calcined clays emerge as a promising source of supplementary cementitious material, which can provide a significant lowering of the Portland clinker content in blended cements. This study focusses on sulfate resistance of calcined clay (CC) – limestone (L) – Portland cements for mortars exposed to a 0.11 M Na2SO4 solution at 5 and 20 °C after a hydration period of 91 days. The pozzolanicity, compressive strength, pore structure, and sulfate resistance of mortars containing laboratory-made metakaolin or calcined montmorillonite and limestone have been investigated in cements with 35 wt% replacement of a white Portland or an ordinary Portland clinker. The results show that all mortars with CC/(CC + L) ≥ 0.5 exhibit excellent sulfate resistance. The consumption of portlandite by the pozzolanic reactions of the calcined clays and the dilution of the Portland clinker lead to a lower amount of calcium available for the secondary formation of gypsum and ettringite, which is identified as the main reason for the excellent sulfate resistance of the ternary blends. The results suggest that calcined clay – limestone – Portland cements are included in standards as a new type of sulfate-resisting Portland pozzolana cement and Portland composite cement.
Sulfate resistance of calcined clay – Limestone – Portland cements
Shi, Zhenguo (Autor:in) / Ferreiro, Sergio (Autor:in) / Lothenbach, Barbara (Autor:in) / Geiker, Mette Rica (Autor:in) / Kunther, Wolfgang (Autor:in) / Kaufmann, Josef (Autor:in) / Herfort, Duncan (Autor:in) / Skibsted, Jørgen (Autor:in)
Cement and Concrete Research ; 116 ; 238-251
05.11.2018
14 pages
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch
Influence of Clay Type on Performance of Calcined Clay – Limestone Portland Cements
| Springer Verlag | 2017
Calcined clay limestone cements (LC3)
| British Library Online Contents | 2018