Research On Finite Element Modeling And Data Extraction Method For Damage Diagnosis Of Cable-Stayed Bridges

The establishment of a benchmark finite element model has become one of the key issues in the damage diagnosis of cable-stayed bridges.Based on this,the static and dynamic response data are extracted as the numerical simulation data for damage diagnosis.Directly creating the benchmark finite element model and data extraction are repetitive and cumbersome.It is of great significance to develop the exclusive module with the secondary development function of ABAQUS to realize the rapid creation of the benchmark finite element model and the rapid extraction of data.This article uses Python programming language for secondary development of ABAQUS and designs a finite element modeling and data extraction platform for damage diagnosis of cable-stayed bridges.The main research work is as follows:(1)Based on ABAQUS and Python,through the coding rules of Python programming language and ABAQUS secondary development interface,using GUI toolkit and RSG constructor,a platform integrating pre-processing finite element modeling,model correction and post-processing data extraction with cable-stayed bridge as the research object is developed.(2)According to the relevant parameters of cable-stayed bridge and combined with ABAQUS software,the script of pre-processing finite element modeling program is written by Python programming language,and the corresponding graphical user interface is developed.Only by editing the model information in the dialog interface,the parametric modeling of cable tower,cable and girder,material property assignment,analysis step setting,interaction,load application and meshing can be completed,which greatly improves the efficiency of ABAQUS pre-processing finite element modeling.(3)Combining the finite element model updating theory with the ABAQUS secondary development theory,the finite element model updating module of cablestayed bridge is developed.The module includes sensitivity analysis,influence matrix extraction and optimization.Using this module,the sensitivity analysis of different design parameters can be carried out,and the design parameters with higher sensitivity can be obtained as the correction parameters.It can also complete the rapid extraction of cable force influence matrix;the corresponding optimization algorithm can also be used to optimize the constructed objective function.Based on this module,the finite element model of cable-stayed bridge can be quickly modified,and the modified finite element model is used as the reference finite element model.(4)For damage diagnosis based on finite element model,it is necessary to extract the response data of the benchmark finite element model of cable-stayed bridge.Therefore,a post-processing data extraction module is developed.With the help of this module,static and dynamic response data extraction can be realized,including displacement,cable force,stress,strain,frequency,vibration mode,velocity and acceleration response data.