Non-linear Finite Element Analysis Of Reinforced Concrete Beams Strengthened With CFRP Sheets

The technology of Carbon Fiber-Reinforced Polymers strengthening concrete structures is a hotspot of research and exploiture in civil engineering fields home and abroad. Which is widely used recently as it presents a high strength-to-weight ratio, excellent economic benefits, high durability in corrosive atmosphere and it can be constructed rapidly and easily, doesn't increase structure sizes nearly. Research on CFRP reinforcing flexural concrete member is focused on experiments and theoretic analysis, however computer emulational analysis should be made more efforts.In order to study the behaviors of RC beams strengthened with CFRP, experimental study and FEM analysis were combined in the process of research. This thesis put forward the results of experimental and analytical studies concerning flexural reinforced concrete beams strengthened with externally bonded CFRP to the tension face of the beams.First, this paper introduces the development of structure reinforcement and research status quo in CFRP strengthening flexural concrete member, and summarizes the material performance of CFRP and adhesive resins systemically.Based on non-linear numeric analysis theory and modeling technology, On the ground of suitable numerical model and numerous calculations, some nonlinear finite element models on strengthened beams were made with element method (separate displacement models were made), which due to proper material elements (SOLID65 and LINK8 were used to model the concrete and steel bar respectively, SHELL41 were used to model the CFRP sheets) and simulation parameters (the elastic modulus and poisson ration and the relation between stress and strain of concrete and steel bar and CFRP sheets were given). ten R.C beams are analyzed in carrying capacity and the load- displacement curves are put out.The paper conducted to the comparison between results of experiment and element simulation. The results of comparison between experiment and element analysis show that the results of experiment is similar to those of models. The data differences of both results varied below 15%. Based on elastic and plastic theory and finite element theory, the paper interprets the reasons why the differences exist. What's more, the models that material homogeneous and perfect bond between the concrete and steel bar and between the concrete and CFRP sheets are assumed not only effectively avoid the randomcity and disperse of experiments, but also perfectly simulate the flexural performance of beams and give some systemic data about flexural performance of beams strengthened with CFRP sheets for analysis and applications.