The Research On Dynamic Model Updating Technology For Arch Bridge Benchmark Building Based On Response Surface Methodology

The model modification technique is based on the experimental data of dynamic and static load test.The initial finite element model based on the design is modified to be consistent with the experimental data,so as to make the structure safe and reliable.The engineering safety research of the model modification technology is important for the evaluation of the operational safety performance of the bridge structure,the response prediction of the structure on various stress conditions and the health monitoring and damage identification of the structure.This thesis briefly introduces the main points of the basic theory in the process of finite element analysis,including the contents,forms and storage methods of various matrices,the method of considering the eccentricity of the section.The finite element analysis program is written on the basis of MATLAB.The interface and the mode of operation focus on the core theory of some of the calculation.The simulation analysis is carried out with the representative bridge of continuous beam bridge,cable-stayed bridge and suspension bridge.Meanwhile the conclusion has also been compared with the general finite element software.This is a groundwork for subsequent model revision analysis.This thesis summarizes the theory,principle and basic steps of the finite element model correction based on the response surface method and elaborates several key links in the process of the finite element model based on the response surface and prepares the finite element model based on the response surface program.A simple numerical model has been used to check the applicability of the response surface method and the correctness of the program.On the basis of the above,this thesis takes the Benchmark model of Shimen Reservoir Bridge as the research object,and modifies the corresponding finite element simulation model.The sensitivity analysis of many design parameters not only can filter out the parameters which have more significant influence on the structural response,but also can greatly reduce the workload.Using radial basis function and polynomial as the response surface function of the arch bridge model response surface model can obtain very accurate.The consistency between the modified model and the Benchmark model is guaranteed,which is used as the reference model for further research or engineering application.Finally,this thesis uses the modified finite element model as the benchmark finite element model of Shimen Reservoir Bridge,simulates the four kinds damage conditions by replacing the sections of the benchmark finite element model,uses two polynomial function as the general form of response surface method and modify correction parameters to analyse the damage.Therefore,the model updating method based on response surface method can predict the damage location and damage degree of the components,which is valuable for engineering.