Applied Technology Analysis Of Internal Reinforcement Corrosion Detection Of Bridgewith Electromagnetic Pulsed Eddy Current Method

Since the reinforced concrete structure widely used in recent decades,the rebar passivation layer caused by concrete carbonization phenomenon and chloride ion damage,leading to internal rebar corrosion,effective cross-sectional area is reduced,concrete and reinforced grip wrapped force decreased,decreased the load-carrying capacity,safety accidents occur frequently.In particular,the corrosion of rebar,there is a danger and concealment.In view of the above background,this paper presents a nondestructive testing technique for the reinforcement corrosion of the bridge by eddy current thermal imaging,the research contents are as follow:First,this paper studied on the rebar corrosion chemical mechanism,analyses the affect factors,including the composition of concrete,carbonization and chloride ions.Second,we made the introduction about the theory of the main elements of eddy current thermal imaging nondestructive testing system,infrared imager,electromagnetic induction heating unit and the reinforced concrete structure detection,while making feasibility analysis of the internal corrosion of bridge detection by this method,we investigated the major factors affecting and influence law of eddy current thermal imaging,the analysis lay the foundation for the design of the experiment.Thrid,we studied the key factor in eddy current thermal imaging method was used to detect the internal corrosion of the rebar reinforced concrete structure,and then we completed the analysis and simulation of this method which established to simulate the theoretical model.We also showed that the relationship between the factors and reinforced the heating efficiency.After that we completed the using of eddy current thermography experiments on internal corrosion detection.Finally,we made the detection of actual bridge,based on the increase of Chongqing Bridge No.two,compared with the results show that the eddy current thermal imaging method is feasible,effective and practical.Based on the eddy current thermal imaging nondestructive testing technology,we took the full advantage of the different change in the relative permeability under corrosion or non corrosion and concrete surface temperature caused by the different growth rate,we provide the quantitative detection method about internal corrosion of the steel bridge site.The method will have great market prospect and practical application value,and it will get huge social and economic benefits.