Wind-Resistent Performance and Aeerodynamic Optimization Measures for Super-Long-Span Bridge with Three-Box Girder
|School||Southwest Jiaotong University|
|Course||Bridge and Tunnel Engineering|
|Keywords||Large span bridges Aerodynamic characteristics Aerodynamic measures CFD Aerostatic stability Flutter stability|
Large Span Bridge is a bridge in the future development of an important direction of the current domestic and foreign large span bridge construction has begun to enter the booming period. However, the bridge span structure tends to increase the lead to soft , damping decreases, structural natural frequency is low, it is easy to occur under natural wind destructive vibrations. Large wind resistance across the bridge has become a controlling factor in the design , construction and operation is to protect the security key . Girder bridge by the wind as the main component , and its aerodynamic performance will directly affect the entire bridge wind resistance . Therefore, the study has a better aerodynamic characteristics of the new -span girder bridge sections on the development of great significance. First, review the domestic and foreign large -span bridge girder wind Research , collect large span bridges have been built section form girder bridges have been built and used in pneumatic examples of measures , an overview of different measures on aerodynamic aerodynamic characteristics of the main beam , as Next to the main beam aerodynamic characteristics and aerodynamic optimization research experience . Secondly , drawing on previously used to identify bridge flutter derivatives methods for CFD numerical simulation , identifying the ideal flat flutter derivatives and obtain its critical flutter speed . By comparing the ideal tablet critical flutter speed of numerical solution and the theoretical solution to prove that the numerical simulation method can be applied to different sections of the aerodynamic characteristics of the bridge comparative study . Again , the use of CFD numerical simulation method to calculate the five kinds of large span bridge girder cross-section in the form of aerodynamic parameters , based on the obtained aerodynamic parameters for each section of the main beam static wind velocity and critical buckling critical flutter velocity is solved , and compare each section aerostatic stability and aerodynamic stability , a comprehensive assessment of each girder sections merits of wind resistance . Finally, with better separation of three wind resistance box girder, six different aerodynamic design measures , by comparing the different sections of the main beam stability and calm wind flutter stability, discussed the measures to set right the aerodynamic separation of three box girder aerodynamic characteristics and aerodynamic measures proposed setting method proposed aerodynamic optimization of the bridge has guiding significance .