Study On Failure Mechanism And Constitutive Relationship Of FRP Confined Concrete Column

FRP reinforced concrete structure began in the 1980s. Compared with the traditional method, the FRP reinforcement method is simple and obvious in the reinforcing effect. It is later for the study on axially compressed concrete columns than beams. However, the axially compressed member is the most common force component. Therefore, it is necessary for the study on FRP confined axially loaded concrete column.At present, fitting the experimental data and element analysis software are used for the study on the axial compression concrete column. But these methods can not get the accurate results since the discrete of the data and different parameter for the finite element model.The study is based on energy division model proposed by Mander J B. It is believed that the total energy of FRP confined concrete columns under axial compression is shared by the fiber cloth and internal concrete according to Mander J B'model. But Mander J B dose not take into account the changes in the internal energy in the process of concrete compression. Mander J B's model is improved. The total energy of FRP confined concrete is divided into three parts. It seeks to simplify the calculation model of the energy for the three parts and analyze the energy distribution relations in the process of FRP confined concrete columns under axial pressure. It is derived formula for ultimate strength for FRP confined concrete columns under axial compression based on energy conservation equation. It has important engineering application value for repairing and strengthening of active concrete structures.