Seismic Performance of Aramid Fiber Square Tubed Concrete Columns with Metallic and/or Non-Metallic Reinforcement

In prefabricated Aramid Fiber Reinforced Polymer (AFRP) tubed concrete columns with metallic and/or nonmetallic reinforcement, the AFRP square tube performs the dual functions of stay-in-place formwork and transverse reinforcement. Nine column specimens including a hybrid concrete column with steel bars or AFRP rods for longitudinal reinforcement, were tested under cyclic lateral forces while simultaneously subjected to a constant axial load. Double confinement due to an aramid fiber tube and steel hoops with cross ties can provide a much greater transverse confinement effect. The ply of composite laminates can be designed such that when the shear and the bond strengths exceed the flexural strengths, adequate seismic performance of the hybrid RC columns can be ensured.