Parametric Sensitivity Analysis Of Special-style Beam-arch Composite Bridge

Special-style arch bridge which is a type of bridge structure with complex and beautiful shape has made a great development in China and become a beautiful landmark at the place where the bridge was built.The experts in the whole world have made some theoretical and experimental researches on the stress and deformation characteristics of this new type of composite structure,however,due to the specificity of special-style bridge,the mutual reference of the research results is not very strong.Based on the Qiancheng road bridge in Zhengzhou,the paper detailed analyzes influences of main parameters such as thickness of steel arch rib,the pre-stress of the strands in the pier,the tensioning force in suspenders,thickness of bridge deck,the thickness of U rib,and the special-style composite arch bridge's stress,deformation characteristics,natural vibration characteristic and elastic stability are investigated.Through the analytical study,some conclusions are obtained,which is meaningful for the design of the same kind of bridge.The main research works and results are as follows.(1)Through the introduction of the development and research status of the steel arch bridge and the special-style composite arch bridge,the purpose and significance of the research are clarified.(2)In this paper,the finite method analysis models are built by commercial software Midas/civil and Midas/FEA.Then the analysis of the stress and deformation characteristics of this kind of structure are conducted under the reasonable finished state of the bridge.And the following work of this paper bases on the characteristics of this reasonable finished state.(3)The single variable method is used to analyze the influence on the mechanical behaior of the structure by changing the structure parameters.The parameters includes the pre-stress of the strands in the pier,the tensile force of suspenders,the thickness of the deck,the thickness of the arch rib and the thickness of the U rib.Then the sensitive parameters are determined.(4)Subsequently,the elastic stability and the natural vibration characteristic ofspecial-style composite arch bridge are made by changing the several structure parameters above.Then the sensitivity of the elastic stability and the natural vibration characteristic to several parameters are obtained.