Numerical Simulation Of Wind Load On Continuous Beam Bridge With High Piers

In recent years,with the development of computer technology and numerical methods,computational fluid dynamics(CFD)has been widely used in the field of wind engineering.In this thesis,the commercial software Fluent is adopted to simulate aerodynamic force coefficient,static gust loads and flow field characteristics of high-pier continuous girder bridge.The main contents include:(1)In this thesis,the prototype of the bridge model in the numerical simulation is Tramo Bridge in Quito,Ecuador,whose main girder is a variable cross-section beam.So the representative bridge deck sections,such as mid-span section and sections at pier top,are analyzed.These bridge deck section's width are 13.5m,and the section height of which is respectively 4.0m,7.0m,and 10.5 m.(2)In uniform flow,the two-dimensional models of above-mentioned bridge deck sections are established,considering wind attack angle is +3°,-3° and 0°,in order to get the change trend of the mean aerodynamic force coefficient and Strouhal number under different wind attack angle.Besides,chapter 3 also analyzes the effect of different section height and wind attack angle on the mean aerodynamic force coefficient,Strouhal number and the flow field.(3)Based on Tramo Bridge in Ecuador,a three-dimensional full-scale model is established in uniform flow,considering wind attack angle is +3°,-3° and 0°.During the calculation,the beam segments with section height of 4.0m,7.0m and 10.5m are monitored separately to obtain the change trend of their mean aerodynamic force coefficient and Strouhal number under different wind attack angle.Besides,chapter 4 also analyzes the effect of different section height and wind attack angle on the mean aerodynamic force coefficient,Strouhal number and the flow.field,and compare with the results in two-dimensional numerical simulation.(4)Through the statistical analysis of the wind speed observation data provided by the ground weather station near the Tramo Bridge station,this thesis simulates the wind characteristic at the bridge site,studies the actual wind environment at the bridge site,and calculates the design wind speed at bridge deck level for 100 years return period.(5)According to the design wind speed and drag coefficient respectively obtained in the numerical simulation of the two-dimensional and three-dimensional models,static gust loads can be calculated.Besides,chapter 5 calculates static gust load in accordance with the specification,and compares it with the above two results.