Strengthen concrete-filled steel tubular column with fiber-reinforced polymer

An innovative column named as fiber-reinforced polymer (FRP) confined concrete-filled steel tubular column was studied. The analytical expression of the load capability was deduced according to the theory of ultimate equilibrium when the confined concrete filled steel tube was suffered from axial compression, and then the working mechanism was analysed. The calculation results followed fairly that observed by the tests. The calculation results showed that ultimate bearing capacity was increased linearly with the increment of the thickness of the FRP, but the ratio of the increment of the ultimate bearing capacity of the stub FRP column was decreased with the increment of the refinement parameter of the steel tube. The formula deduced provided dependable theoretical foundation for design of FRP confined concrete filled steel tubular column.