Numerical Analysis Of The Mechanical Properties Of FRP Bars And Hybrid Fiber Reinforced Self-compacting Concrete Beamss

As a new type of building material,FRP bars have a good application prospect.Compared with steel bars,FRP bars can fundamentally solve the problem of corrosion,and also have the advantages of light weight and high tensile strength.Hybrid fiber self--compacting concrete is a new type of composite material with two or more fibers added into the self-compacting concrete base.Addition of fiber can enhance the crack resistance of concrete and improve the mechanical properties of concrete materials.Combining FRP bars with hybrid fiber self-compacting concrete,the numerical analysis of the flexural shear behavior of FRP bars with hybrid fiber self-compacting concrete has certain engineering significance and value.This article in self-compacting concrete mixed with different dosage of basalt fiber and polypropylene fiber,through 16 groups of hybrid fiber reinforced self-compacting concrete and 1 set of ordinary self-compacting concrete cube cube compressive strength,splitting tensile strength test,analysis under different hybrid fiber content changes of the mechanical properties of self-compacting concrete.The corresponding stress-strain curves of prisms of different groups of specimens were tested,and the experimental curves were compared with the existing constitutive equations.The results showed that the test curves in the ascending section had a higher fitting effect with the formula,among which the constitutive equation in reference [67] had the highest fitting effect.The constitutive equation of reference [67] is improved,and the ascending equation which is more consistent with this test is proposed.Based on the constitutive equation fitted by experiment,the finite element model of FRP bars hybrid fiber self-compacting concrete beams was established by ABAQUS software,and the failure modes of different members were simulated and the load-deflection curves of different members were analyzed.The flexural performance of FRP reinforced composite self-compacting concrete beams was analyzed with the volume content of composite fibers,the ratio of longitudinal bars and different types of tensioning bars as variables.The shear performance of FRP reinforced composite self-compacting concrete beams was studied with the volume content of composite fibers,the ratio of longitudinal bars,different kinds of tensioning bars and the ratio of tensioning bars as variables.The results show that with the same basalt fiber,different polypropylene fiber content has little influence on the flexural and shear performance of FRP reinforced self-compacting concrete beams.The flexural capacity of FRP reinforced beams is greater than that of reinforced beams,but the shear capacity of FRP reinforced beams is smaller than that of reinforced beams.The effect of reinforcement ratio on the flexural performance of FRP beams is greater than that of fiber content and different reinforcement types.In the shear performance of FRP bars,the stirrup spacing has the greatest effect.With the increase of stirrup spacing,the shear capacity of FRP bars decreases.When the stirrup spacing is 200 mm,the failure mode changes and becomes cable-stayed failure.