Simultaneous influences of nanomaterial and fiber reinforcement on enhancing the mechanical performance of geopolymerstabilized soft clayey soils

• Nano-metakaolin (20% replacement) in slag-based geopolymer increases soil strength ~21 times and reduces compression index by ~70%. • Higher curing temperature enhances polymerization kinetics, leading to ~2 times improvement in soil solidification. • Fiber reinforcement boosts energy absorption capacity ≥10 times and improves residual strength, overcoming brittleness of NM-stabilized soil. • Combined LGNMF treatment offers broader economic, technical, and environmental benefits, promoting ductility of geopolymer-stabilized soil.