Mechanical Analysis Of Prestressed Fiber Reinforced Pressure Pipeline

FRP has many advantages,such as light weight,high strength,corrosion resistance,fatigue resistance,etc.,and it has been widely used in various kinds of reinforcement projects to reinforce FRP.In recent years,the damage of steel fiber reinforced prestressed technology to repair has been increasingly popular,but in the prestressing process,how to determine the value of prestressed reinforcement is the key problem to solve prestressed fiber pipelineThe paper analyzes the mechanical behavior of pressure pipeline reinforcement of prestressed fiber,mainly for prestressed fiber reinfo rced pressure pipeline buckling strength failure and in-depth research.The theoretical analysis is provided for the repair of pressure pipeline by prestressed fiber reinforcement.The main work can be described as follows:(1)The author sums up the basic research methods,on shell buckling instability can type and stability analysis of the buckling of model is the most suitable method of steel fiber reinforced prestressed concrete,namely Rayleigh Ritz method,Rayleigh Ritz method is a variational approxi mation method based on the principle and the principle of minimum potential energy.According to the deflection function assumed by buckling deformation is the key method to solve the buckling problem of Leeds pipeline under the action of outside.(2)The critical buckling analysis of prestressed steel pipe is sdudied.The mechanical model of steel fiber reinforced prestressed concrete is established,according to the curvature equation,equilibrium equations,geometric equations,derived the physical equations of the pipe deflection differential equation under prestressing,and found the limiting strain in the center pipe load symmetrically.(3)According to the shape of shell buckling,buckling process is divided into pre buckling process and post buckling process.Considering the effect of the film stress,according to the geometric equations,equilibrium equations,physical equations,according to Saint Venant theorem,deduces the deformation coordination equation and buckling control equation of steel tu be under prestressing,the Ritz method,according to the deformation of the steel pipe under prestressing,deflection differential equation of steel tube under prestressing,according to the minimum potential principle,the steel tube buckling under prestressing critical value.(4)The elastoplastic analysis is studied under the action of prestressing force.According to the mechanical model of prestressed steel pipe,the distribution of circumferential stress and radial stress of steel pipe under the action of prestressing force is obtained.Based on the strength theory,the elastoplastic problem of steel pipe under the action of prestressing force is analyzed,and the distribution law of circumferential stress and radial stress of steel pipe is obtained.(5)The experiment is studied on prestressed steel pipe.Through the experiment of prestressed fiber reinforce steel is verified by theory of theoretical formula of stress and strain,and the distribution of prestress in steel pipe strain direction and axial direction of the ring.