Analysis And Application Of Structral Vibration Characteristics Based On Nedium And Low Speed DIC Neasurements

Structural vibration characteristics analysis is a multidisciplinary research field,which involves many fields,such as materials,measurement control,mechanics,mechanical equipment and general information,so it has been the focus of the research.Structural displacement and structural vibration frequency are the basic parameters of the dynamic characteristics of mechanical systems,and also it is an important monitoring index for mechanical normal operation.At present,the methods of measuring the frequency of structural displacement and structural vibration are piezoelectric sensor,strain gauge method and laser vibration measurement.However,in many engineering practices,these methods are limited by the test environment and operating conditions,which makes the conventional measurement method not applicable.In this paper,the method of digital image correlation analysis is used to measure the structure displacement and vibration frequency of the object.The method has the advantages of full field measurement,non-contact,high precision,large measuring range and low requirement to the measurement environment.This method solves the problems in the vibration process of materials,and further expands the application range of digital image correlation analysis method.This paper mainly uses the measurement information of digital image correlation analysis to study the vibration experiment process of materials under load,and then lays the foundation for structural health monitoring,including:1.In this paper,the research progress of existing digital image correlation analysis in mechanics,structural health monitoring method,and structural vibration characteristics are reviewed;The research status of digital image correlation analysis method in static load and dynamic load test and its advantages and disadvantages are summarized.The measuring principle of steady state vibration measurement module based on digital image correlation analysis method is introduced;2.In the low speed camera as a tool to measure the low order structure displacement and the structure of the vibration frequency of the structure;and then get the modal parameters of the test,and compared with the theoretical results,the result shows the feasibility of the method for measuring the structure of the low order vibration frequency and vibration type,the applicability of the measurement method and compared with traditional better.3.Based on the measurement information of the structure vibration characteristics of low speed camera,using the damage locating vector methods for the health monitoring and diagnosis research of structure;displacement flexibility matrix expression structure is derived,in the relevant simulation software of the beam specimens and the modal analysis and harmonic response analysis,and then analyzes the test beam damage identification based on damage localization process the vector method of structure displacement,flexibility matrix of beam formation,the structural displacement in the flexibility matrix before and after damage of the difference matrix singular value decomposition,the displacement of each unit beam finite element model is solved in each load vector under the action of value,rules of total displacement identification to locate the damage area of beam structure,surface digital image correlation analysis method in the damage identification process effectiveness of related parameters.