Static And Dynamic Analyses And Optimization Of Tied Arch Bridge With Composite Deck

Firstly,the thesis introduces the characteristics,development and structural forms of the steel box tied arch bridge.Secondly,the design scheme and main component design parameters of the urban tied arch bridge with span of 112 m composite deck are summarized.The full bridge model based on beam element was built by the finite element software.The truss elements was used to simulate the boom,the beam elements to simulate the main beams and arch boxes,and the plate elements to simulate the bridge panel.A full bridge model based on beam element,truss element and plate element was built by using finite element software Midas/Civil.The construction process of steel box tied arch bridge is simulated,and the deformation,internal force and stress of each member are calculated and analyzed.The effects of constant load,live load,wind load and temperature are combined and loaded according to the most adverse conditions to calculate and analyze the deformation,internal force and stress of each member of the bridge in the operation stage.Using the general finite element software Abaqus,the local detailed full-bridge model based on solid element,plate and shell element was established,and Lanczos method was used to calculate the natural vibration characteristics of the bridge and the characteristics of the bridge modes.The response spectra of E1 and E2 were input into the Midas/Civil model which based on beam elements to calculate the seismic response of each member of the bridge.Considering the actual situation,the time history of ground motion acceleration is selected to calculate the response of each part of the bridge.Based on the anchor box and arch foot detailed Abaqus full bridge model established by Abaqus,the stress distribution of each component in the locally stressed pieces of nchor boxes and arch foot under constant load and vehicle load was calculated respectively.Finally,in the Midas/Civil bridge model,based on the construction plan of adjusting the internal forces of the derrick for three times,the amplitude modulation of the internal forces of the cable is used to change the derrick tensioning from three times to once,optimize and simplify the construction steps.