Fatigue Behaviors of High-Speed Track Slabs Reinforced by GFRP Composite Rebar: Full-Scale Experimental Verification

This study deals with the fatigue behavior of on-site-installation-type track slabs subject to cycling train load developed by applying glass-fiber-reinforced polymer (GFRP) reinforcing bars. Concrete track slabs have the most severe deterioration in track circuit characteristic values due to the conduction influence of existing steel bars. Therefore, a track slab applying an insulator and lightweight GFRP reinforcement by replacing the existing steel bar was proposed from a design perspective. In order to present the validity of the proposed method, a full-size specimen was manufactured and a fatigue performance test was performed, and the results were compared with the test specimen applied with steel bars. From the results of various fatigue behaviors, it was found that displacement variations during cyclic loading remained within 1 mm, and load variations were within 10 kN, indicating excellent stability under accumulated fatigue cycles. This study analyzed the macro-level structural behavior of GFRP-reinforced concrete track slabs under fatigue loading. Future research will further investigate micro-level bond interactions between the reinforcement and concrete to validate long-term performance.