Experimental Evaluation of Demountable GFRP Dowel Bar System Incorporating Steel and FRP Rings in Precast Concrete Pavements

This study presents an experimental evaluation of a demountable Glass Fiber-Reinforced Polymer (GFRP) dowel bar system incorporating steel and Fiber-Reinforced Polymer (FRP) rings for concrete pavement applications. The primary objective of this research is to investigate the load-transfer behavior and structural performance of the proposed system and to compare its response with conventional steel ring configurations. An experimental program was conducted using concrete joint specimens subjected to monotonic vertical loading, where load–displacement behavior, load transfer capacity, and failure characteristics were evaluated. The experimental results indicate that specimens incorporating FRP rings exhibited superior performance compared to those with steel rings. The maximum load capacity increased by approximately 30–35%, reaching peak values of about 60kN, while the corresponding vertical displacement was reduced by nearly 20–25% relative to reference specimens. Furthermore, the GFRP-based systems demonstrated improved post-peak behavior and more stable load–displacement responses, indicating enhanced load transfer efficiency and reduced stress concentration at the joint interface. Overall, the proposed demountable GFRP dowel bar system shows significant potential as a sustainable and efficient alternative to traditional steel dowel systems in concrete pavements, offering improved mechanical performance, corrosion resistance, and ease of disassembly and replacement.