A modeling and experimental study of concrete columns highly confined by carbon fibre reinforced polymer sheets

Through a previous study of the FRP confined cylinders, it was discovered that concrete plastic deformation will exhibit different characteristics for columns with higher confinement compared to those with lower confinement. This paper addresses an experimental study which involves 39 cylinders with different plies of CFRP sheets from one to five. The lateral stiffness ratio (ρ=2Eftf/Dfc') ranges from 14.90 to 145.22. The modified model for a plastic dilation angle (β) can capture the development of plastic deformation efficiently in a wide range of lateral stiffness ratio compared with other dilation angle model. Meanwhile, this paper address es the modeling of FRP confined concrete within the framework of modified Drucker- Prager plasticity model. Simple models for friction angle and cohesion are adopted subsequently to verify the performance of the modified plastic dilation angle model. Using the commercial software ABAQUS, finite element analysis results fit well with the experimental stress-strain behavior of concrete columns with FRP confinement in a large range of the lateral stiffness ratio.