Master’s Thesis on the Bond Behavior Between GFRP Bars and Concrete Under High Temperature Exposure

A master's thesis defense was held at the College of Engineering – University of Kirkuk for student Ahmed Yahya Ghaib from the Department of Civil Engineering, entitled:
“Evaluation of Bond Strength Between GFRP Bars and Concrete Exposed to High Temperatures”

The study presented an in-depth investigation into the mechanical performance of Glass Fiber Reinforced Polymer (GFRP) bars embedded in concrete when subjected to elevated temperatures simulating fire conditions in reinforced concrete structures.

A total of 36 concrete specimens were tested to evaluate their thermal and mechanical properties, stress–slip behavior, residual compressive strength, and failure patterns.

The results showed a significant negative impact of high temperatures on bond strength, with a recorded decrease of up to 73.23% in some cases at 600°C, particularly in centrally positioned bars with a diameter of 16 mm. The concrete cover thickness and bar location (center vs. edge) were also found to affect the degree of degradation.

These changes were attributed to epoxy resin decomposition, thermal expansion of the bars, and increased slippage under heat exposure.

The study concluded that fire conditions must be taken into account when designing concrete structures reinforced with GFRP bars, in order to develop constructions that are more resilient and fire-resistant.

The examination committee consisted of:

• Prof. Dr. Asim Mohammed Lateef – Chair

• Asst. Prof. Dr. Khamees Naif Abdul-Haleem – Member

• Dr. Hammad Dhari Marai – Member

• Prof. Dr. Mueyed Mohammed Qasim – Member and Supervisor

At the conclusion of the defense, the committee commended the student's outstanding scientific effort, and the thesis was approved as fulfilling the requirements for the Master’s degree in Civil Engineering / Structural Engineering.