Valorization of a Steel Industrial Co-Product for the Development of Alkali-Activated Materials: Effect of Curing Environments

Abstract While natural resources are becoming scarce and climate change is accelerating, the recovery recycling of wastes by-products an effective way to deal with economic ecological constraints recent decades. The valorization industrial in civil engineering a common practice either by their incorporation during manufacture Portland cements or as partial replacement cement production concrete. present work aims develop waste-based alkali-activated materials WAAMs intended for applications potential alternative cement-based materials. A steel by-product called commonly granulated blast furnace slag GBFS was used alone solid CaO-rich precursor; two alkaline activators such us sodium silicate (Na 2 SiO 3 ) hydroxide (NaOH) were separately two-part Besides microstructure analysis hardened samples, influence activator/precursor mass ratio, NaOH molarity, curing environments (Room temperature 60°C) on compressive strength, water accessible porosity, loss, drying shrinkage assessed. results showed that high Liquid/Solid ratio leads decrease strength while molarity significantly improves mechanical properties reducing porosity specimens. Moreover, activator provides higher strengths compared activator, especially when samples cured at room where maximum 28days-compressive value 105.28 MPa achieved. For activated using solution, revealed 60°C promotes obtaining initial-compressive (7 days) before decreasing subsequently function time. As indication, concentration (NaOH = 9M), decline 21% recorded between time 7 28 days. induced significant loss shrinkage. SEM highlighted dense, homogeneous without apparent defects, particular alkali used.