Based On The Dynamic Characteristics Of The Structure Damage Identification Research

In recent years,a large number of civil engineering structure more and more,there have been a large number of large span,large volume,large space,high,ultra-deep structure,its healthy operation related to the people,property security,but also related to the country and social stability.The life span of the civil engineering structure varies from a few decades to a hundred years.During the course of its operation,the erosion of the environment,the aging of the material,the load and the effects of various abrupt effects will have a great influence on the structure.If the critical structural component damage in a certain period of time to be accumulated,the damage will be rapidly expanded,causing the destruction of the entire structure.In this paper,the frequency parameters and curvature parameters are studied.On the basis of the simple beam,the change law of the frequency before and after the damage and the identification of the structural damage of the different curvature modal parameters are analyzed.For the three-span continuous beam bridge,the combination of the first and second curvature is studied and the damage location is judged.The main research contents are as follows:1.Summarize the research data of structural damage identification based on dynamic characteristics,and classify and analyze various damage identification methods.The basic theory of structural damage determination method(frequency change method and curvature modal analysis method)is analyzed,and the application of frequency variation method and curvature mode method is analyzed and summarized.2.Before and after the damage of the simple beam,the frequency damage quantity,the frequency change ratio,the square change ratio of the frequency change and the regularization frequency change rate are analyzed and studied,and the law of frequency change is summarized.3.Before and after the damage of the simple beam,the curvature of the curvature of the modal value,the curvature modal difference,the curvature modal ratio,the curvature of the modal rate of change and the average curvature of the modal damage factor on the curvature of the five damage analysis parameters,Modal recognition of damage.According to the advantages of the two methods of frequency parameters and curvature parameters,the damage identification method of a three-span continuous beam bridge is studied by using the combined method,and the appropriate damage detection system is constructed.