Case Studies in Construction Materials (Dec 2021)
Effect of waste glass bottles-derived nanopowder as slag replacement on mortars with alkali activation: Durability characteristics
Abstract
Various alkali-activated binders (AABs) incorporated with different industrial wastes emerged as useful environmental affable materials in the construction sectors as alternative to the traditional cement due to their lower CO2 emission and landfill problems mitigation. The sustainability of concretes is the major global concern in the construction sectors. In this view, the effects of waste glass bottles-derived nanopowder (WGBNP) on the durability characteristics of five batches of alkali-activated mortars (AAMs) with the inclusion of fly ash (FA) and ground blast furnace slag (GBFS) were evaluated. These AAMs were designed via the replacement of GBFS at various WGBNP contents (0%, 5%, 10%, 15% and 20%). Analytical tests were performed to determine the mortars compressive strength, porosity, drying shrinkage, and resistance to aggressive environments. Microstructures characteristics were assessed using XRD measurements. Replacement of GBFS by WGBNP was found to remarkably improve the durability traits of the produced AAMs, solving the environmental and landfill problems. The results indicated that the inclusion of 5% of WGBNP in alkali-activated matrix led to the reduction of porosity and enhancement of the strength and durability performance. Additionally, the replacement of GBFS by WGBNP was found to improve the durability performance in terms of reduced drying shrinkage and increased resistance to sulphuric acid, wearing, and freeze-thaw cycles. The obtained AAMs were demonstrated to be environmentally beneficial regarding the lowering of global warming.