Mechanistic Research And Application Of Carbon Fiber Materials For Reinforcing Reinforced Concrete Beam And Column Structures

Carbon fiber composite material(CFRP)is mainly a composite material composed of fiber(CF)as reinforcement and polymer as matrix together,which is brittle and tough at the same time.Since the 1940 s carbon fiber composites have appeared in the public eye,and with the development of the social,carbon fiber cloth has gradually become the field of automobile,construction,aviation,etc.Scholars’ research on it has gradually deepened,and the fields in which it can be applied are gradually expanding.Carbon fiber cloth is relatively light in quality and high in strength.In addition,carbon fiber cloth also has the advantages of high temperature resistance,corrosion resistance,and the ability to damp vibration,etc.Low thermal expansion can make carbon fiber work for a long time in a high temperature environment,and its density is about one-fifth of steel,so it has a very broad prospect in the reinforcement project.At present,there are more theoretical studies on carbon fiber reinforcement,but less studies on its reinforcement of RC beam members with hollow drums in actual reinforcement projects,and less studies on carbon fiber reinforced RC long column members.Therefore,this paper makes a simulation study for these two aspects.In this paper,based on a strengthening project in Hefei City,beams and columns were selected to analyze and compare the performance differences of the members before and after strengthening through theoretical calculations,and the main influencing factors of the strengthening effect were analyzed based on the theoretical level.By means of ABAQUS finite element software,models of reinforced concrete beam and column members were established before and after strengthening,and the ultimate loads and stresses of the members were calculated by applying displacements to them,and the corresponding analyses were made on these data.The simulation calculation results of the beam and column members were analyzed,and the influence of factors such as the number of layers of carbon fiber cloth pasted on the reinforcement effect of the members was studied in depth;in the analysis of the reinforced beam members,the influence of the location of the hollow drum phenomenon on the reinforcement effect of the reinforced concrete beam members in the reinforcement was analyzed in conjunction with the actual reinforcement,which is very instructive for the actual reinforcement project.Meanwhile,in the reinforcement analysis of reinforced concrete column members,different reinforcement solutions are considered at different parts of the surface of the column members,and relevant models are established to compare and analyze and derive the best reinforcement solutions through simulation calculations.The main conclusions obtained from the study in this paper are as follows:(1)The increase in the number of layers of carbon fiber cloth paste has a significant increase on the ultimate load of reinforced concrete beam and column members,and the two show a positive correlation,but it is worth noting that the number of layers of carbon fiber cloth paste is not infinitely increased,the more the better,when it reaches a certain value,and then increase the number of layers,it will make the reinforcement effect of the members improve slowly and the project cost increase.(2)The width and spacing of pasted carbon fiber cloth have obvious effects on the reinforcement effect of reinforced concrete beam members,and no obvious effects on the reinforcement effect of reinforced concrete column members,and there is a negative correlation between the width and spacing of carbon fiber cloth and the reinforcement effect of beam members.(3)Pasting carbon fiber cloth on both sides of the reinforced concrete beam members can effectively improve the shear resistance of the beam members.(4)When the reinforcement method of carbon fiber cloth is used to strengthen reinforced concrete beam members,the reinforcement effect of the member is significantly affected when the location of the bulge appears in the span of the beam,and the reinforcement effect of the member as a whole is not significantly affected when the location of the bulge is on both sides of the beam member.(5)In the actual reinforcement project,the damage of the column members should be strictly determined,and a reasonable and economic reinforcement design should be carried out for them.If the damage in the encrypted area at both ends of the column members is slight,only the middle position of the column can be reinforced.