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Geopolymer Based on Mechanically Activated Air-cooled Blast Furnace Slag.

ABSTRACT: An efficient solution to increase the sustainability of building materials is to replace Portland cement with alkali-activated materials (AAM). Precursors for those systems are often based on water-cooled ground granulated blast furnace slags (GGBFS). Quenching of blast furnace slag can be done also by air but in that case, the final product is crystalline and with a very low reactivity. The present study aimed to evaluate the cementitious properties of a mechanically activated (MCA) air-cooled blast furnace slag (ACBFS) used as a precursor in sodium silicate alkali-activated systems. The unreactive ACBFS was processed in a planetary ball mill and its cementing performances were compared with an alkali-activated water-cooled GGBFS. Mixes based on mechanically activated ACBFS reached the 7-days compressive strength of 35 MPa and the 28-days compressive strength 45 MPa. The GGBFS-based samples showed generally higher compressive strength values.

SUBMITTER: Tole I

PROVIDER: S-EPMC7085006 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Geopolymer Based on Mechanically Activated Air-cooled Blast Furnace Slag.

Tole Ilda I Rajczakowska Magdalena M Humad Abeer A Kothari Ankit A Cwirzen Andrzej A

Materials (Basel, Switzerland) 20200304 5

An efficient solution to increase the sustainability of building materials is to replace Portland cement with alkali-activated materials (AAM). Precursors for those systems are often based on water-cooled ground granulated blast furnace slags (GGBFS). Quenching of blast furnace slag can be done also by air but in that case, the final product is crystalline and with a very low reactivity. The present study aimed to evaluate the cementitious properties of a mechanically activated (MCA) air-cooled ...[more]

PMID: 32143319

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