Experiment Study On Strengthening Main Arch By External Prestressing

The application of external prestressing on bridge is early, gradually along withdevelopment of new material, new technology and protective measures, externalprestressing reinforcement method has becomed one of the most effective methods inold bridge reinforcement. The external prestressed method, which is safe and reliable,without traffic interruption and changing the structure shape, not damage the structureand increases the structure self weight, is a very convenient reinforcement method. Atpresent, external prestressing is usually used in beam bridge reinforcement, very rarein arch bridge reinforcement.The main arch ring of reinforced concrete arch bridge is mainly a compressionmember, the cracking on the main arch, especially the transverse and radial cracks onmain arch seriously affect structure safety. There are more serious cracks on archspringing and vault of main arch ring of reinforced concrete arch bridges, the paperresearches the initiative external prestress reinforcement; designs the externalprestressing scheme used in the main arch ring reinforcement of the reinforcedconcrete Arch Bridge; Prestressing in the vault and arch springing, reasarches theeffects of the prestress reinforcement on the structure stress and deformation of thevault and arch springing sections and some other key sections; Considering main archring and arch construction joint action, FEA analyse the deformation and stress in themain arch ring before and after reinforcement; According to the results from the finiteelement model of main arch ring of a reinforced concrete arch Bridge reinforced withexternal prestressing, the loading test verifies the results from the FEA, to ensure thefeasibility of the application in the engineering.Study on the enrichment and development of arch bridge reinforcementtechnology has theoretical and practical significance.