Nondestructive Detecting Experiment Of Bridge Internal Reinforcement Corrosion Based On Eddy Current Thermal Imaging

Since the widespread use of reinforced concrete structures in recent decades,The carbonation of concrete and reinforced passivation damage are caused by chloride ions'penetration into the concrete.At the same time Steel corrosion happens and the reinforced cross section area decreases significantly.Therefore,bearing capacity and the grip of reinforcement and concrete decreases.Factors all above are important reasons which endanger the safety of the concrete bridge seriously.Appointing to the background above,this paper puts forward nondestructive testing technology of internal reinforcement corrosion of bridge based on eddy current thermal imaging.Firstly,the influence of concrete carbonation,chloride ion and concrete material composition in reinforced concrete structure to reinforcement corrosion are analyzed based on the research of the mechanism of reinforcement corrosion chemical.The dangers of bridge steel corrosion within the overall structure of the bridge is elucidated.Bridge internal reinforcement corrosion of thermal imaging eddy current nondestructive testing system of basic theory of the main components which is including tested object(reinforced concrete bridge),infrared detectors(infrared thermal imager)and electromagnetic induction heating unit is introduced.The method feasibility of Eddy current thermal imaging to detect bridges reinforcement corrosion was analyzed.Eddy current thermal imaging to detect the main influencing factors are summarized.Thus laid a foundation for the next test scheme design.Then,The theoretical model is established based on the key factor research of eddy current thermal imaging method to detect the internal reinforcement corrosion.The key factor and the relationship between the heating time is founded by Simulation analysis.The Nondestructive Detecting Experiment Internal Reinforcement Corrosion of Bridge based on Eddy Current Thermal Imaging is completed on this base.At last,rely on the No.2 Zeng Jia Bridge,real bridge test and application is completed.Indoor test and real bridge test results show that the method is feasible,effective and practical.This paper put up with the result of nondestructive detecting experiment on bridge internal reinforcement corrosion based on eddy current thermal imaging,which can make full use of the different concrete surface temperature increase rate due to the relative permeability difference tetween the corroded reinforced and the un-corroded reinforced.And solve the major problem that bridge internal reinforcement corrosion on-site inspection can only be qualitative,not quantitative detection.This method has a broad market prospect and application value,and will generate huge economic benefits and social benefits.