Study On The Size Effect Of Axial Compression Performance Of Reinforced Concrete Circular Column Confined By GFRP

The Fiber Reinforced Plastics(FRP)has been widely used in engineering for its property of tall strength, small density, anti-corrosive and easiness to machine etc. The GFRP reinforce technology is an effective reinforcement method, can not only protect the reinforced concrete structure from the corrosion of the external environment, but also can effectively limiting concrete lateral deformation, so as to improve the compressive strength, ductility and mechanical performance of the concrete. The existence of size effect of concrete column has become an accepted fact, but there is little study about the size effect of GFRP reinforced concrete circle columns. In the paper, the size effect of GFRP reinforced concrete is studied by the combination of experiment and finite element numerical method.The main research contents and results are as follows:1. The paper establishes load- strain curve, load-displacement curve and stress-strain curve of GFRP reinforced concrete column by observing the failure process, failure modes and ultimate bearing capacity in cylindrical pressure test. Then the size effect of reinforced concrete columns confined by GFRP cloth with geometry similarity is analyzed;2. The axial compression test of GFRP confined reinforced concrete column is simulated by the finite element software ANSYS and the ultimate compressive strength and load-displacement curve is established. The results of simulation and experiment are compared to verify the feasibility of the model;3. The finite element model is used to analyze the effect of three kinds of reinforcement ratio, GFRP distribution ratio and concrete strength on the size effect of GFRP fabric reinforced concrete column. The research result show that with the increase of reinforcement ratio, sheet volume allocation ratio and concrete strength grade, the larger the specimen size,the greater the ultimate compressive strength increase, then the size effect will be improved.With the increase of the size of the specimen, the effect of GFRP cloth is better.