Static Analysis And Wind-Induced Vibration Response Analysis Of Suspension Bridge

As the increases of bridge span ,the change of long and narrow declining it's stiffness and damping. Suspension bridge as a long span,flexible structure, because of its sensitivity to wind, the stability under wind has become a key factor in design and construction. Seasonal winds in coastal areas and amplificated wind in mountain valleys makes large speed on bridge. As a result the static and dynamic wind loads are also large, so the analysis of wind-induced response has important practical value.Xinjiang Saiuo Diego Bridge, is a single span 278m of steel truss bridge,on an high wind speed area; with two 4m distance main cables and 1/69.5 wide-span ratio. use 45°wind resist cable to increase its stiffness then to increase its wind strength. theoretically the medium-span suspension bridge wide-span ratio should be larger than the 1/30, the bridge can has enough lateral rigidity. It is necessary to do some research on wind resistance of suspension,contains structure static response,dynamic response analysis and wind resistance control measures.This paper summarize the development process of the wind resistance, mechanical features and characteristics of dynamic wind. On the basis of it, take Saiuo Diego Bridge as example do some systematic study of the stability under wind, including analysis of static response, galloping, flutter critical wind velocity and buffeting response analysis.First, this paper use harmonic synthesis, put forward by George Deodatis, to complete the simulation of turbulent wind, in the algorithm introduced fast Fourier transform(FFT), and carried out spectral correlation tests.Secondly, use large-scale finite element software ANSYS to establish the bridge mould with wind resistant cablet, and do static and dynamic analysis.Finally, to determine the bridge flutter, galloping and buffeting critical wind speed as a method of judging the stability, buffeting response analysis is the key point.By calculating study found the wind-resistance cable structure can significantly improve the natural frequency and produced very effective results.