Buffeting Analysis In Time Domain For Long-Span Steel Arch Bridge

With the development of steel arch bridge to long and super long-span, the research on vibration caused by wind has become more and more important. Based on the present frequency and time domain analytical methods, a nonlinear time domain method is developed. This paper is carried out to analyze the buffeting of long-span steel arch bridge in operation and erection stage. The research is mainly focused on the following aspects: Based on the present AR(p) method, the AIC rule is used for fix the rank of the AR model to improve the simulation precision. Take into account that the wind speed spectrum is vary with the height for the long-span steel arch bridge, simulate the fluctuating wind field. The expression of motion-excited aerodynamic force in time domain is obtained in the form of pulse response function putted forward by Lin. Using this form of motion-excited force, the influences of the displacement, velocity and acceleration of bridge structure and the nonlinear time-delay effect are fully considered. Through the dynamical characteristic analysis, static analysis and buffeting analysis of Caiyuanba Changjiang River Bridge, and compared with the results of wind tunnel tests, the reliability and validity of the method is validated. Based on the analysis of bridge in operation stage, the time domain method is applied in buffeting analysis of long-span steel arch bridge in erection stage. The buffeting responses of Caiyuanba Changjiang River Bridge in different erection are investigated.