Study of a binder based on alkaline activated limestone

• Published in: Construction & building materials Vol. 311; p. 125323
• Main Authors: Cousture, Annelise, Renault, Norbert, Gallias, Jean-Louis, Ndiaye, Khadim
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 13.12.2021; Elsevier
• Subjects: Alkali-activation; Civil Engineering; Engineering Sciences; Limestone; Materials; Matériaux composites et construction; Pirssonite; Portlandite; Thermal analysis; Pirssonite; Limestone; W/B; XRD; Alkali-activation; TGA; DTA; AS/L; S/L; FTIR; EDX; SEM; Portlandite; Thermal analysis
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2021.125323

•New binder based on limestone activation by concentrate solution of sodium hydroxide.•Mortars with optimized composition reach 20 MPa at 28 days.•Reaction products are pirssonite and portlandite.•SEM-EDX measurements allowed the identification of the microstructure of pirssonite.•Balanced quantification of reaction products and remaining reactants was developed. Binders based on the alkaline activation of raw materials is a subject of increasing importance for construction. This study focuses on a new non-hydraulic binder based on the alkali-activation of limestone by an aqueous solution of sodium hydroxide. An optimized mortar of about 20 MPa compressive strength, made with siliceous sand, was studied by XRD, FTIR and SEM-EDX analyses showing that crystalline pirssonite and portlandite are the reaction products responsible of the cohesive capacity of the binder. A methodology based on thermal gravimetric analysis was applied to quantify the products formed and the consumption of reagents with high reliability.