Pre-stressed FRP-concrete composite structural members

摘要

Fiber reinforced plastic FRP formed about concrete piles and columns. The FRP components generally includes an exterior shell and an interior protruding portions. The concrete filled FRP tubes are enhanced by prestressing the concrete core, thereby increasing the bond with the tube and placing the tube in an active hoop tension. The prestressing can be developed by either post-tensioning a series of strands(or tendons) that are placed inside the core, or by using expansive core materials which do expand upon curing and will therefore impose an active pressure on the confining tube. The bond can be developed by either internal resin grids, FRP spirals, FRP orthotropic grids, sand- resin coating, bonding agent or protruded ribs. The system can be used as a fender pile, bearing pile, bridge pier column, or any structural column. The system can be made by pultrusion, SCRIMP, REM, centrifugal methods or hand lay-up. The invention can additionally enhance the compressive, flexural and shear strengths of concrete support columns and piles especially for infrastructures such as bridges, buildings and the like used in hurricane and seismic zone locations.