Behavior of GFRP reinforced concrete exterior beam-column connections under cyclic loading

Reinforced concrete (RC) structures are susceptible to the corrosion of steel reinforcement in harsh environments such as coastal areas or extremely cold regions. Corrosion of steel reinforcing bars causes the cracking of the concrete cover as well as deterioration of bond and strength properties, resulting in decreased structural performance. As a result, the service life of the concrete structure is reduced. Fiber-reinforced polymer (FRP) bars have emerged as a viable option for overcoming reinforcement corrosion in RC structural elements due to their high resistance to chloride and chemical attacks. Previous investigations on FRP reinforced structural members have revealed that glass fibre reinforced polymer (GFRP) bars have sufficient strength and ductility under monotonic loading. However, the structural behavior of GFRP-RC exterior beam-column connections has not been adequately understood as yet. This research study investigated the behavior of the GFRP reinforced concrete (GFRP-RC) exterior beam-column connections (BCCs) under cyclic loading. The study was divided into experimental and numerical phases. The primary goal of this research study is to propose connection reinforcement details capable of improving the ductility and energy dissipation of FRP-RC BCCs. Moreover, the effects of critical parameters (compressive strength of concrete, axial load on column, connection geometry, longitudinal reinforcement ratio of the beam and transverse reinforcement ratio in the connection panel) on the behavior of GFRP reinforced exterior BCCs were investigated.