| With the development of civil engineering structure in China towards higher height,larger span and more complex structure form,modal testing of large and complex structure to obtain the dynamic characteristics of the structure and to carry out state assessment and safety early warning has become a hot issue in academia.How to acquire more accurate and complete structural responses from large and complex structures is the first problem to be solved in modal testing.For this reason,scholars at home and abroad have put forward a series of evaluation criteria for optimal sensor placement to guide the selection of measuring points and improve the accuracy of information collection in modal test.However,using these criteria to select test points needs to be based on the theoretical modal parameter information of the structure,and needs a certain theoretical and computational basis.It is difficult for front-line engineers to use these research results to guide the sensor placement for large and complex engineering structures.The calculation of the optimal sensor placement needs to be based on the theoretical modal information of the target structure,and the acquisition of the theoretical modal information rely on the finite element model,and the theoretical modal information of the structure that needs to be acquired by the optimal sensor placement need a good node corresponding relationship,which undoubtedly increases the difficulty of acquiring the theoretical modal information of the target structure,In this paper,the extraction methods of theoretical modal information of finite element model of commonly used software ANSYS,ABAQUS and Midas civil are developed.Based on MATLAB platform,the pre-processing function module of optimal sensor placement software is formed,which can generate the theoretical modal information of the target model according to the user’s choice.Because Midas civil doesn’t support the information of stiffness and mass matrix,this paper develops a model transformation program between Midas civil and ABAQUS,which transforms Midas civil model into ABAQUS model and extracts theoretical modal information.With the help of APP designer,software development tool of MATLAB platform,the optimal sensor placement software（OSPS）for complex engineering structure is designed and developed from the perspective of user use and the realization of the function of measuring point optimization.The software combines the functions of target model information extraction,model reconstruction,target evaluation criteria selection,candidate sensor location selection,layout scheme visualization and output optimal sensor placement layout report with multiple functional interfaces.The software supports one click extraction of model information such as ANSYS,ABAQUS,Midas civil,etc.,realizes one click to reconstruction of target model in the software,integrates 17 kinds of commonly used evaluation criteria of optimal sensor placement,and users can select one or more criteria to calculate at the same time to obtain a visual layout scheme of optimal configuration and export the layout report with one click.The software has simple interface,friendly operation and good practicability.Midas civil model of a concrete-filled steel tubular arch bridge is transformed into ABAQUS model by using the program developed in this paper.By comparing the modal analysis results of this model in two software,the correctness of the conversion program is proved.Then,the optimal sensor placement configuration of the model is carried out by using the software developed in this paper,which verifies the practicability of the OSPS software for the bridge structure.Finally,the OSPS software is used in the actual building structure.Taking the ABAQUS model of a high-rise building as an example,the OSPS software is used to select some nodes on the vertical components as candidate sensor location,and optimize the layout of measuring points according to the two horizontal mode shapes,the results show that the OSPS software can be used to optimize the layout of measuring points of high-rise building structure,and has good engineering practicability. |
