Study On Mechanical Behavior Of Inclined Section Of Reinforced Polyvinyl Alcohol Fiber Reinforced Concrete Beams

Fiber reinforced concrete is a new composite material,which is usually made of concrete,mortar or cement paste as the base material,and organic fiber,inorganic fiber or metal fiber as the reinforcement material.The mechanical properties of concrete can be improved obviously by adding fiber into concrete.Compared with ordinary concrete,fiber reinforced concrete has better tensile strength,better impact toughness,and improves the impermeability,waterproof and frost resistance of concrete.Polyvinyl alcohol fiber(PVA fiber),also known as polyester fiber in China,is a kind of synthetic fiber,which is made of high-quality polyvinyl alcohol(PVA)with high polymerization degree as raw material and processed with specific advanced technology.Compared with other fibers,PVA fiber has strong adhesion;insoluble in solvent,good wear resistance and protective colloid;water resistance after special treatment;good affinity and binding with cement substrate.Compared with other fibers,PVA fiber can effectively improve the mechanical properties of concrete.In the past,the main research on PVA fiber concrete is the performance of materials.There are few researches on PVA fiber components.This paper studies the mechanical properties of reinforced PVA fiber beams with different fiber content,concrete strength,section size and reinforcement ratio.(1)Using the finite element software to analyze the shear failure process of reinforced PVA fiber reinforced concrete beams,to understand the influence of the above factors on the shear performance of the members,and to provide the basis for the experimental study of reinforced PVA fiber reinforced concrete beams.(2)Through the shear test of reinforced PVA fiber reinforced concrete beams with different concrete strength and section size,it can be concluded that with the increase of concrete strength and section size,the bearing capacity of fiber reinforced concrete beams is improved,which shows that the strength grade and section size of concrete are important factors affecting the bearing capacity of test beams.(3)The finite element analysis results of reinforced PVA fiber reinforced concrete beams are compared with the experimental analysis results.In order to verify the accuracy of the research results,and provide the basis for the finite element analysis of reinforced PVA fiber reinforced concrete beams with more parameter changes.The results show that.(1)Through the shear test of reinforced concrete beams with different PVA fiber volume ratio,it can be concluded that adding PVA fiber to concrete can improve the tensile strength of concrete with the increase of PVA fiber volume ratio.With the increase of PVA fiber volume ratio,the occurrence of inclined cracks is delayed and the crack resistance of concrete beams is improved.The increase of PVA fiber volume ratio reduces the stirrup stress under the same load.(2)Through the shear test of reinforced PVA fiber reinforced concrete beams with different concrete strength and section size,it can be concluded that with the increase of concrete strength and section size,the bearing capacity of fiber reinforced concrete beams is improved,which shows that the concrete strength grade and section size are important factors affecting the bearing capacity of test beams.(3)Through the shear test of PVA fiber reinforced concrete beams with different reinforcement ratio,it can be concluded that with the increase of reinforcement ratio,the bearing capacity of concrete beams is improved,the occurrence of inclined cracks is delayed,and the anti cracking performance of concrete is improved.