A New Concrete-Filled Hollow Frp Composite Column

An effective use of fiber reinforced plastic (FRP) shapes in infrastructure is in the form of composite construction with reinforced concrete. A novel composite column is proposed that is similar to the classic concrete-filled steel tubes, except that steel has been replaced with a hollow FRP shell. The FRP shell, while an integral part of the structure, is also the pour form for concrete. The shell may be a filament-wound or a multi-layer FRP pipe with a layer of longitudinal fibers sandwiched between two piles of circumferential fibers. The proposed column offers high strength and ductility in addition to excellent durability. Behavior of the proposed column is studied by developing two analytical tools; a new passive confinement model for externally reinforced concrete columns, and a composite action model that evaluates the lateral stiffening effect of the jacket. Results are compared with recent studies of fiber-wrapped columns