The effect of mine waste ratio and curing duration on the mechanical properties of ground granulated blast furnace slag-based geopolymer mortars


Aksüt Y. S., NAS E., Sünnetçi K., Kaya Y.

Canadian Journal of Civil Engineering, vol.53, 2026 (SCI-Expanded, Scopus) identifier identifier

  • Publication Type: Article / Article
  • Volume: 53
  • Publication Date: 2026
  • Doi Number: 10.1139/cjce-2025-0389
  • Journal Name: Canadian Journal of Civil Engineering
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Artic & Antarctic Regions, Compendex, Environment Index, Geobase, ICONDA Bibliographic
  • Keywords: geopolymer mortar, mechanical performance, microstructure, mining waste, SEM–XRD analyses
  • Karadeniz Technical University Affiliated: Yes

Abstract

This study investigates the mechanical and microstructural behavior of ground granulated blast furnace slag (GGBFS)-based geopolymer mortars in which mining waste (MW) was used as a partial binder replacement (0–30%) under ambient water curing for 7–90 days. Increasing MW content reduced workability and slightly prolonged setting due to its coarser and less reactive characteristics. Mechanical performance improved with curing time and mixtures with moderate MW levels achieved the best strength and microstructural densification. Water absorption and porosity decreased with age, reflecting progressive gel formation. Scanning electron microscope–X-ray diffraction (SEM-XRD) analyses verified matrix densification and enhanced gel development at intermediate MW ratios. Overall, the findings show that controlled MW incorporation can optimize the balance between strength, pore structure and sustainability, enabling ambient cured GGBFS-based geopolymers without thermal curing. The study provides new insights by using MW as a binder phase replacement while preserving precursor chemistry, a rarely explored approach.