Experimental Research On The Beams Strengthened Under Cyclic Loading

The old building’s reinforcement is one of emerging professions in the presentconstruction industry, and the reinforcement of concrete structur approximately composesabove50%. enlarging section method is one important method of concrete structurereinforcement,at present the researches of bearing performance of strengthened concretemembers by enlarging section are less. So the paper mainly studies on bonding methods ofnew to old concrete interface and mechanical performance under cyclic load for strengtheningof RC beam,which are significant for theory and practice.The enlargement section method of embedded steel bars technology is proposed in thispaper, and four contrast beam were designed and made.Through the unidirectional repeatedloading of structure test, it analyses and compares failure characleristics, load-deflection curve,bearing capacity and ductility performance. This article put forward the reinforcement beamcapacity formula.The results show that it increased planting reinforcing bar on the new-oldconcrete interface, it can effectively improved mechanical performance, to ensure new-oldconcrete working together, it make the reinforced concrete beams strengthened reaches thedesign goalforces,deformation performance and improve the ductility performance.These results as above have the certain reference for the further study of theenlargingsection method, and can also perfect the criterion about the design of the concretereinforcement and reconstruction, which are available for actual reconstruction project designand construction.