An experimental approach for the determination of the physical and mechanical properties of a sustainable geopolymer mortar made with Algerian ground-granulated blast furnace slag

Abstract Geopolymer technology is widely recognized and extensively tested as a sustainable alternative to conventional cement, with considerable environmental and economic benefits through waste management; however, it remains largely unstudied and underutilized in Algeria. Despite the abundant availability of aluminosilicate materials, there is only limited and incomplete research on pozzolans and metakaolins in the region. This article aims to address this gap by investigating the use of Algerian ground-granulated blast furnace slag (GGBFS) to develop an optimal formulation for producing high-performance geopolymers. To determine the optimal combination of alkaline activators compatible with GGBFS and sand content, a series of experiments were conducted on fresh and hardened GGBFS-based geopolymer mortars (GPMs) to verify properties such as workability, setting time, water absorption, efflorescence stability, and mechanical strength. Techniques used to characterize the microstructure of a subset of geopolymer samples included attenuated total reflectance – Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy – energy dispersive X-ray spectroscopy. This research not only emphasizes the environmental benefits of repurposing waste materials but also advances the development of more sustainable and durable GPMs, presenting a promising approach to improving environmental stewardship in material science practices.