The aim of this experimental study is to evaluate the flexural behavior of bamboo-reinforced geopolymer concrete (GPC) slabs incorporating industrial by-products as sustainable alternatives to conventional reinforced concrete. To reduce the environmental impact associated with Portland cement, steel reinforcement, and natural aggregates, geopolymer concrete reinforced with treated bamboo was developed using sodium silicate waste (SSW) as a 40% replacement for coarse aggregate and copper slag (CS) as a 50% replacement for fine aggregate. Four slab panels, namely bamboo-reinforced cement concrete, bamboo-reinforced geopolymer concrete (GPC), SSW-blended GPC, and CS-blended GPC, were fabricated and tested under simulated uniformly distributed loading. The structural response was evaluated in terms of load-deflection behavior, first-crack load, ultimate load, stiffness, ductility index, deformability factor, and energy absorption capacity. Compared with the cement control, the GPC slab increased the first-crack load by 26% and the ultimate load by 8%. The SSW-blended GPC slab achieved an ultimate load of 50 kN and exhibited the highest ductility index (4.20), while the CS-blended GPC slab demonstrated the best overall structural performance with the highest ultimate load (52 kN, 6% higher than the GPC slab), stiffness (12.3 kN/mm), and energy absorption capacity (1748 kNmm). The results demonstrate that integrating alkali-activated binders, industrial by-products, and bamboo reinforcement can produce structurally efficient and environmentally sustainable slab systems. Among the investigated mixes, the CS-blended geopolymer slab exhibited the most balanced combination of strength, stiffness, and toughness, highlighting its potential for sustainable structural applications.
