Numerical Analysis Of Dynamic Characteristic And Damage Identification On External Prestressing Construction

Externally prestressed concrete structure is a branch of post-tensioning unbonded prestressed concrete structure, its concept first comes from France, is one structure system that totally use prestressd steel which out of concrete section to apply vertical prestress. Since the development of the unbonded prestressed concrete and the cable-stayed system, solved the durability and structure design problem of prestressd steel. Make the external prestressed structure a flourishing development.This paper is based on experiment of simply-supported T beam which study the application of external prestressing technique, it is the sub-project of Liaoning provincial communication department’s important scientific research project. Use finite element software of ANSYS to calculate the modal frequency bands and modes through modal analysis of reinforced concrete structure and external reinforced concrete structure. Prove the reliability of method which using the finite element software of ANSYS analyzing structure’s dynamic characteristic.This paper introduced the dynamic calculation methods on Bernoulli-Euler beam and external prestressing structure, mainly studied the reinforcement and externally prestressing reinforcement’s effect on dynamic characteristic of simply supported T beam. Concretes with various strength levels, different value of effective prestress, different sectional areas of external prestressed tendons, different position of anchorage and deviators have impacts on external prestressing beam’s dynamic characteristics. Consider the impact on dynamic characteristic of crack and corrosion of bar, study the difference dynamic characteristic before and after the damage. Briefly introduced the reinforced concrete structure’s damage identification method which is based on vibration testing. Through the modal analysis of the damaged model, put forward a reliable damage identification method applicated on reinforced concrete and external prestressed concrete structure. Prove the reliability of method which using the finite element software of ANSYS to simulating structure’s damagement.