| The steel truss bridge has the advantages of homogeneity and light weight,easy to be manufactured in a factory,convenient for construction without support,fast installation speed,good seismic resistance,easy recycling,etc.,and has been widely used.However,the monitoring during the construction process and subsequent operation and management are very demanding,and the traditional detection methods face the problems of manual operation,time-consuming and labor-intensive,few measured data points,and low degree of automation,which can no longer meet the needs of modernization.Digital image technology has the advantages of non-contact,multiple measurement points,high precision,high spatial density,good repeatability,no equipment loss,etc.,and can make up for the shortcomings of traditional measurement methods.This paper demonstrates that digital image processing technology can be used to measure the deflection before and after the cantilever beam is assembled,and combined with virtual reality technology,a simulation system for the construction process of the bridge structure is initially established;digital image processing technology is used to obtain the dynamic response data of the structure,and the modal parameter identification is performed,and the identification results are compared with the results of the traditional test method and the finite element method,and the feasibility of digital image processing technology in structural dynamic analysis is analyzed.The main content and research results of this paper are as follows:(1)Introducing the history of bridge development in China and the achievements and problems of bridge construction,explaining the research background and significance of this topic,consult relevant materials,and summarizing the research and application status of related technologies at home and abroad.(2)The theoretical basis of digital image detection technology and virtual reality technology,the basic principles and application methods of digital image detection technology and virtual reality technology are introduced,and the camera calibration workflow and effects are specifically explained.(3)Using traditional detection technology to conduct vibration research on the steel truss bridge model,introduce the dynamic response into the DASP system,and obtain the first five order frequencies and mode shapes after analysis.(4)The finite element software is used to establish the finite element model of the steel truss beam,and the finite element model is modified based on the parameter sensitivity analysis based on the relevant modal parameters obtained by the traditional detection technology.(5)Digital image detection technology is used to detect the linear change of the cantilever segment during the cantilever assembly process,the data is imported into the virtual reality environment,and the assembly construction process is presented.(6)Using digital image detection technology to study the vibration of steel truss bridge model,compare the modal parameters obtained from the analysis with the modal parameters obtained by traditional detection technology,and demonstrate the feasibility of digital image detection technology.(7)Summarizing the work done in this article,analyze the existing deficiencies and problems,and propose prospects for future research and applications. |
