Finite Element Model Updating Of Concrete Filled Steel Tube Arch Bridge Based On First Order Optimization Algorithm

Due to the bridge in the service process inevitably affected by environmental erosion, material aging, various load repeatedly and other factors influence that they appeared different degree of damage, only by nondestructive test and load test it is difficult to make accurate assessment. Along with the progress of science and technology and the continuous development of the finite element technology, the numerical model of the bridge structure can be realized. The research on bridge damage identification, state evaluation and response prediction by the combination of non destructive testing, load testing and numerical simulation has become the focus of domestic and foreign scholars on the safety assessment of bridges. The main research contents and contributions of this thesis are as follows:(1) The refined finite element model of the bridge structure was established by ANSYS, and the static and dynamic response data of each working condition were extracted. The theoretical data and field test data were compared and analyzed to find out the influence factors of the error.(2) According to the analysis of field test process and test data comparison, advantages of dynamic testing the relative static test, and select the dynamic test data as a finite element model correction benchmark, using the static test data and experimental data to verify the feasibility of the method.(3) Through the orthogonal test, the factors were analyzed, and then the influence degree of the structural response was determined by the level of significance, so that the correct order of each parameter was determined.(4) According to the order of the parameters, the parameters are modified by using first order optimization algorithm, and the design variables, state variables and objective functions are all satisfied with the constraint requirements.(5) After extracting the static data of the modified finite element model and comparing with the field measured data, the static characteristic of the modified finite element model is verified.(6) Through extraction modified finite element model of vehicle bridge coupling vibration data and measured roadster and field data for comparative analysis, verify that the modified finite element model of dynamic characteristics.