Development of damage-controlled latter cast FRP–RC hybrid girders

A type of fiber reinforced polymer (FRP)–reinforced concrete (RC) hybrid structure as one kind of novel construction with integrated structural performances is addressed. The FRP–RC hybrid structure designed under a damage-controlled methodology is composed of external hybrid FRP shells and a RC core. The bonding of interior walls of the hybrid FRP shell and cast RC core is realized through epoxy resins under wet condition. The external hybrid FRP shell consists of carbon FRP with high strength and high modulus as longitudinal reinforcements and glass FRP with high ductility as both longitudinal and shear reinforcements. In addition, the external hybrid FRP shell provides the concrete core and steel rebars with an effective protection against corrosion. A series of 4-point bending experiments are performed to study the structural performance of FRP–RC hybrid girders designed and fabricated under the concept of damage-controlled methodology. Based on the bending theories, the flexural properties of the developed structures are also evaluated. The investigation reveals that the damage of FRP–RC hybrid structure is controllable and that the wet bonding is effective.