Experimental Study on the Structural Performance of Glass-Fiber-Reinforced Concrete Slabs Reinforced with Glass-Fiber-Reinforced Polymer (GFRP) Bars: A Sustainable Alternative to Steel in Challenging Environments

The inherent brittleness of glass-fiber-reinforced polymer (GFRP) bars limits their structural applicability despite their corrosion resistance and lightweight properties. This study addresses the critical challenge of enhancing the ductility and crack resistance of GFRP-reinforced systems while maintaining their environmental resilience. Through experimental evaluation, GFRC slabs reinforced with GFRP bars are systematically compared to steel-reinforced GFRC slabs and non-bar-reinforced SFRC slabs under bending loads. Eight slabs were subjected to four-edge-supported loading following standardized procedures based on prior strength assessments. The results demonstrate that GFRP-reinforced GFRC slabs achieve an ultimate load capacity of 83.7 kN, comparable to their steel-reinforced counterparts (96.3 kN), while exhibiting progressive crack propagation and 17% higher energy absorption than non-fiber-reinforced systems. The load capacity similarities between GFRP-bar-reinforced GFRC slabs and steel-reinforced slabs are 69% for crack loading and 86% for ultimate capacity. Furthermore, this study demonstrates that the reduction factor in flexural strength design of the novel slab should be comprehensively considered, incorporating the recommended value of 0.5. The findings confirm that GFRP-bar-reinforced GFRC slabs meet key structural performance criteria, including enhanced bending capacity, energy absorption, crack resistance, and ductility. This study underscores the potential of GFRP as an effective alternative to steel reinforcement, contributing to the development of resilient and durable concrete structures in demanding environments.