Research On Mechanical Property Of Steel Plate Symmetrically Bonded CFRP

Previously,many researches on steel plate bonded CFRP were started from the point of sticking CFRP reinforcement to repair steel structure.This paper is no longer limited to this research angle,but takes steel plate symmetrically bonded CFRP as a whole to study the mechanical properties of the new metal matrix composite.In this way,the study of the combination of steel plate and CFRP from the perspective of a new material will facilitate the prefabrication of reinforcement materials in the factory,reduce the on-site workload,and facilitate the construction.This paper studies the symmetrical rather than the unilateral bonded style that is commonly used,because the force of symmetrical style is more reasonable,and it can make better use of the corrosion resistance of CFRP to protect the inner steel plate from rust.This bonded style is more worthy of popularization.In view of steel plate symmetrically bonded CFRP,the material properties,constitutive relation and interfacial stress of the material are studied from three aspects of theory,test and finite element analysis.Through the elastic theory,this paper analyses the change of internal stress of the composite material when the axis is pulled.12 groups of tensile tests of standard specimens were made to study the effect of different steel plate thickness,different CFRP layers and thickness of different adhesive layers on the mechanical properties of the composite material.On the basis of theory and experiment,the finite element analysis model is modified,and the constitutive model of the composite and the change of interfacial stress are further determined.Through the analysis of stress theory,the formula for calculating the peel stress on the bonding interface between CFRP and steel plate is obtained when considering the axial deformation of the composite material and the deformation of the thickness of the inner steel plate.The effects of the different ratio of the three components on the mechanical properties of the composite material are obtained through the experimental study.Through experiments and finite element analysis,it is concluded that the constitutive relation of the composite material under the condition of small deformation is a bilinear constitutive model.Through the finite element analysis,the influence of six factors on the shear stress and peel stress on the interface of thecomposite material is obtained,including the material properties and thickness of thesteel plate,the material properties and thickness of CFRP,and the material properties and thickness of the adhesive layer.