Study On Calculation Method For Deformmation Of Reinforced Concrete Columns With Fiber Reinforced Concrete In Plastic Hinge Region

For frame structure, the deformation capacity of the whole structure is determined by that of each frame column. To improve the deformation ability and the seismic behavior, the fibre reinforced concrete(FRC) was applied to the plastic hinge region of reinforced concrete column, which is high strength, high ductility, tensile strain hardening and strong damage resistance, can significantly improve the seismic behavior, etc. Study on seismic behavior and deformation of FRC column and frame structure, which has good theory significance and practical value.Nine FRC column specimens and one reinforced concrete column specimen were designed and the quasi static tests were carried out, which was simulated by Open Sees. Based on the test data and the parameters of the simulation results, section static equilibrium equation and cross section geometric deformation of the plane section hypothesis have been developed to derive the curvature of the columns with FRC in plastic hinge region in different ultimate limit state. According to the curvature distribution of column, a top horizontal displacement caused by the bending deformation was derived by integraling along the column. Using Sezen model, the top horizontal displacement caused by the bond-slip between longitudinal reinforcement and concrete at bottom of the column has been obtained by using the curvature distribution of column. The top horizontal displacement caused by shear deformation was considered. The calculated displacements of the cracking, yield, the peak load and the limit state are in good agreement with the test results.For analyzing the overall deformation ability and proving correctness of the model of frame structure with the FRC in the plastic hinge region of columns, the static elastoplastic analysis by Perform 3D and SAP 2000 software for the frame structure with FRC in the plastic hinge region of columns was carried out. The results show that the frame structure with the FRC in the plastic hinge region of columns, bearing capacity can be increased by 30%-40%, the yield displacement and the displacement at peak load both are increased, the shear- top displacement curve is downed slowly.