The Study Of Mechanical Shape On RC Beams Strengthened With The Pre-stressed CFRP And Pre-screwed Bolts

Prestressed CFRP reinforcement technique was applied to harm for the bridge reinforcement method in bridge reinforcement project is a very good supplement,improve the deficiency of the existing bridge reinforcement method,the prestressed CFRP strengthening technology can effectively increase the ultimate bearing capacity of Bridges,to improve the mechanical properties of the bridge,inhibit the development of the cracks,reduce the deflection of bridge deformation,improve the effective utilization of carbon fiber cloth.But will the bridge reinforcement technology is the very good application in practical bridge reinforcement project,there are certain problems in the main performance on the CFRP prestressed tensioning system(existing tensioning device and anchor device operation trival,take up the space is big,the damage to the bridge itself,etc.).In this paper,on the basis of existing tension system and principle,and combining with the characteristics of carbon fiber cloth itself,designed and developed a set of new tensioning system;Design the 9 6 m long test beams,the large scale test and research,is closer to the actual bridge project;Which USES the set of new tensioning system of eight test,strengthened beams with prestressed CFRP on 8 experimental beams,single,double,three layers of carbon fiber cloth paste reinforcement;Imposed by the initial prestressed degree 25%,50%and 75%respectively,and the eight test beam mechanical anchoring steel plate is adopted to improve the anchoring,the eight test beam using homemade reaction frame to four-point bending load.Test results show that the new research and development of carbon fiber cloth tensioning system can complete and set the size of the initial stress of carbon fiber,and installation of equipment is easy to operate,high construction efficiency;Strengthening technology with prestressed CFRP and preloaded bolt joint strengthening reinforced concrete beam can be effectively improved by reinforcement beam ultimate bearing capacity,increase the reinforced beam bending stiffness,reducing the deflection deformation and inhibit the development of the cracks,the carbon fiber cloth to give full play to the performance of high strength,impro ve the mechanical properties of the bridge.Through analyzing the prestressed CFRP strengthening RC structural behavior research,this article through the theoretical calculation and experimental results analysis compared the ultimate bearing capacity,deflection and crack propagation of change,the theoretical calculation and experimental results are in good agreement,summarizes the prestressed carbon fiber sheet(CFS)and preloaded bolt joint force mechanism of bridge reinforcement.Using the reinforcement technology designed to reinforce the dhi rizhao-heze expressway spokesman line of Dong Ping K137 + 128 channels,obvious effect,summarizes on the set of new tensioning system strengthening construction technology.