Research On The Mechanical Properties Of Reinforced Concrete Square Columns Strengthened By Carbon Fiber Cloth And Glass Fiber Cloth

CFRP and GFRP are two kinds of materials commonly used in CFRP reinforcement.Compared with carbon fiber reinforced composites,which have high tensile strength,high elastic modulus and low elongation,glass fiber reinforced composites have lower tensile strength and high elongation.Studies have shown that the combination of two kinds of fiber materials can effectively improve the weakness of single fiber materials,better play to the advantages of the two materials,and improve the comprehensive mechanical properties of fiber materials.At present,the method of combinations of two kinds of fibre materials mainly combination between layers,and provided the combination of study is less,this article through to 1 root reinforcement of reinforced concrete square columns and 4 root paste fiber reinforcement of reinforced concrete square columns(paste,respectively,the single single CFRP and GFRP,combination between the layers of CFRP/GFRP,namely the combination of CFRP/GFRP)of the axial compression test,found that:(1)CFRP/GFRP combined between layers and CFRP/GFRP combined within the same layer can effectively improve the axial compression bearing capacity of reinforced concrete square columns,and the lifting rate is above 30%,reaching more than 85% of the lifting rate of the bearing capacity of the test column completely wrapped with a single CFRP.Moreover,the axial deformation capacity of reinforced concrete square columns can be significantly improved with a lifting rate of 170%,which is much better than that of single CFRP reinforcement.with the same proportion of fiber materials,the lifting rate of the axial bearing capacity of the composite CFRP/GFRP within the same layer to the column is higher than that of the interlaminar composite CFRP/GFRP,but the lifting rate of the axial deformation capacity of the column is slightly lower than that of the interlaminar composite CFRP/GFRP.The experimental conditions were simulated by ABAQUS finite element software,and the influence of fiber material ratio in CFRP/GFRP combined in the layer on the axial compression performance of reinforced concrete square columns was modeled and analyzed.It was found that:(1)The finite element simulation results are similar to the test results,with roughly the same change rule,which mutually verify the accuracy of their respective tests.(2)Within the range measured in this test,the more CFRP used in the fiber cloth,the stronger the fiber cloth's ability to lift the bearing capacity of the test column.The higher the amount of GFRP used in the fiber,the higher the ductility of the fiber to the test column.(3)When the use ratio of CFRP/GFRP in the same layer is CFRP: GFRP=1:2,the axial bearing capacity of reinforced concrete square columns can be effectively improved,and the lifting rate reaches 80% of a single CFRP,with better ductility lifting capacity and better economic benefits.