Nonlinear FEM Analysis of Circular Concrete Column Confined with FRP under Axial Compression

By using nonlinear FEM program ABAQUS,the mechanical behaviors of circular concrete column specimens confined with FRP under axial compression were analyzed,considering the nonlinear behavior of concrete under triaxial state and the passive confinement of FRP for concrete.The interaction between concrete and FRP was studied,and the influence of FRP layers on the ultimate strength and strain of concrete was studied.The results indicate that the numerical results agree well with the test results.Nonlinear FEM analysis can better predict the axes compressive properties of FRP confined concrete column.The ultimate strength and strain of FRP confined concrete increase with the increase of FRP layers.The confinement effect of FRP on concrete has obviously improved.The confinement force of FRP on concrete will exert mainly after concrete yield.Based on the experimental results and FEM analysis,the relationship between the ultimate strength and strain of FRP confined concrete and FRP confinement eigenvalue is derived.