To address steel corrosion issues in externally prestressed steel-concrete composite beams, a novel externally prestressed FRP-concrete (FRP-PC) hybrid beam is proposed by replacing steel girder, reinforcement, steel strands, and stud with GFRP profiles, GFRP bars, CFRP tendons, and GFRP bolts. The proposed hybrid beam demonstrates considerable potential for large-span bridge applications, due to its lightweight, high strength, excellent corrosion resistance, and ease of construction. Two large-scale simply supported hybrid beams with different shear connection degrees (η = 0.8/1.2) were tested to investigate their static behavior. Test results revealed that FRP-PC hybrid beams suffered FRP shear failure at the upper flange-web joint (η = 1.2) and interfacial connection failure (η = 0.8). Load-deflection curves demonstrated an initial linear elastic phase followed by a stiffness degradation phase. Both load-carrying capacity and stiffness increased with higher shear connection degrees. Despite the presence of significant interfacial slip, indicating partial composite action between the FRP and concrete, the concrete slab and FRP beam maintained identical curvature throughout loading, thereby validating the plane-section assumption. A validated nonlinear finite element model was developed in Abaqus v2017, considering interfacial slip, material isotropy, and FRP damage. A parametric study on 27 hybrid beams was then conducted to evaluate the effects of shear connection degree, concrete strength, prestress level, concrete slab dimensions, and FRP geometry.

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