Optimization Analysis Of Key Design Parameters Of Netted Boom Arch Bridge Based On Uniform Test Design

The lightness,graceful shape,good bearing,large spanning capacity and superior technical and economic indicators of the mesh boom arch bridge are gradually attracting the attention of the bridge industry,but at present China still lacks a perfect method and basis for the design of mesh boom arch bridges,usually using empirical formulas or referring to the design parameters of other bridge types for calculation,resulting in designs that are often too conservative and cannot highlight the mechanical advantages of mesh boom arch bridges.To this end,this paper relies on a144 m span net boom arch bridge to optimise the key design parameters of the net boom arch bridge,with the following main research elements:(1)Through the collection of relevant information at home and abroad,the development history,current status of research and research deficiencies of the web suspension bar system arch bridge are systematically summarized and summarized,the research background and significance of this paper are explained,the research content and ideas of this paper are proposed,and the basic ideas and methods of uniform test design and multi-objective optimization problems are introduced.(2)The finite element analysis model is established by using MIDAS finite element analysis software in the background of the actual project,and the static and dynamic performance is analysed,and the finite element analysis models of three different types of boom arrangements,namely vertical boom,Nelson system boom and mesh boom,are established to compare and analyse the internal force influence lines of the key parts of the three types of tied arch bridges,which visually reveals the advantages of mesh boom arch bridges in terms of force The advantages of the webbed arch bridge are revealed.(3)Combined with the mechanical properties of the mesh arch bridge,the four key design parameters of boom inclination angle,number of booms,sagittal-to-span ratio and internal inclination angle of the arch ribs were selected,and the effect of single-factor homogeneous method on the internal force,displacement and boom force of the arch ribs and main beam of the mesh arch bridge was investigated,revealing the variation law between the structural internal force and each design parameter of the mesh arch bridge,and giving its reasonable value suggestions.(4)Considering the coupling effects between the sagittal-to-span ratio,boom inclination angle,number of booms and internal inclination angle of the arch ribs of the webbed arch bridge,in order to determine the optimal combination of design parameters,a homogeneous experimental design is carried out for the multi-parameter combination,regression analysis and backward analysis are used to assess the degree of influence of different design parameters on the static and dynamic analyses,and the results are compared and verified with those of the single-factor test vibration analysis.Finally,the multi-objective optimisation was carried out by the TOPSIS ideal point method according to the case of simultaneous optimal solutions under multi-objective functions.