Flutter and Buffeting Analysis in Time Domain for Suspension Bridge in Operation and Erection Stage

A time domain method was developed to analyze the flutter and buffeting of suspension bridge. The effects of nonlinear characters, different flow conditions were all considered. The flutter and buffeting analysis’s results of Humen and Jiangyin Bridge show good agreements with the wind tunnel tests. The happening of flutter is a fairly sudden course in uniform flow, while it is a smooth course in atmospheric turbulent flow. But turbulent flow has disadvantage effects on the flutter stability of suspension bridge with streamlined section. The effect of fluctuating wind should be taken in consideration in the calculation of motion-excited aerodynamic force. The changing law of the flutter critical wind speed in different erection stages is found: in early stage, the critical speed is low, while in middle and later stages it is much higher. Unsymmetrical erection is favorable to the improving of flutter stability.