Experimental Investigation of Bond Strength of Concrete with Glass Fiber Reinforced Polymer Bar under Static Loading Condition Using Pull-out Testing

The bond strength between Glass Fiber Reinforced Polymer (GFRP) bars and concrete is a critical factor in determining the ability and effectiveness of this alternative reinforced material compared to traditional steel reinforcement in structural applications, especially under static loading conditions. Despite the increasing use of GFRP bars due to their physical property, corrosion resistance, high tensile strength, and lightweight nature, there is a notable lack of research studies addressing their bond behavior with concrete under static loading. This study aims to focus on filling this gap by investigating the bond strength and the factors affecting the bond between GFRP bars and concrete. The study employs pull-out testing that applies gradual increases in loading to know how GFRP bars behave under this testing. It was compared to traditional reinforcement to know if it can be used as an alternative reinforcement in structures that require crucial bond strength. The findings revealed that GFRP bars exhibit lower bond strength than steel, with an observed reduction of about 17.404%. Additionally, an inverse relationship between bar diameter and bond strength was identified. The results provide valuable insights into the performance of GFRP reinforcement, highlighting its benefits and limitations, and supporting its potential use in concrete structures.