TY - JOUR
T1 - Aerodynamic coupling effects on flutter and buffeting of bridges
AU - Chen, Xinzhong
AU - Matsumoto, Masaru
AU - Kareem, Ahsan
PY - 2000/1
Y1 - 2000/1
N2 - The effects of aerodynamic coupling among modes of vibration on the flutter and buffeting response of long-span bridges are investigated. By introducing the unsteady, self-excited aerodynamic forces in terms of rational function approximations, the equations of motion in generalized modal coordinates are transformed into a frequency-independent state-space format. The frequencies, damping ratios, and complex mode shapes at a prescribed wind velocity, and the critical flutter conditions, are identified by solving a complex eigenvalue problem. A significant feature of this approach is that an iterative solution for determining the flutter conditions is not necessary, because the equations of motion are independent of frequency. The energy increase in each flutter motion cycle is examined using the work done by the generalized aerodynamic forces or by the self-excited forces along the bridge axis. Accordingly, their contribution to the aerodynamic damping can be clearly identified. The multimode flutter generation mechanism and the roles of flutter derivatives are investigated. Finally, the coupling effects on the buffeting response due to self-excited forces are also discussed.
AB - The effects of aerodynamic coupling among modes of vibration on the flutter and buffeting response of long-span bridges are investigated. By introducing the unsteady, self-excited aerodynamic forces in terms of rational function approximations, the equations of motion in generalized modal coordinates are transformed into a frequency-independent state-space format. The frequencies, damping ratios, and complex mode shapes at a prescribed wind velocity, and the critical flutter conditions, are identified by solving a complex eigenvalue problem. A significant feature of this approach is that an iterative solution for determining the flutter conditions is not necessary, because the equations of motion are independent of frequency. The energy increase in each flutter motion cycle is examined using the work done by the generalized aerodynamic forces or by the self-excited forces along the bridge axis. Accordingly, their contribution to the aerodynamic damping can be clearly identified. The multimode flutter generation mechanism and the roles of flutter derivatives are investigated. Finally, the coupling effects on the buffeting response due to self-excited forces are also discussed.
UR - http://www.scopus.com/inward/record.url?scp=0034010957&partnerID=8YFLogxK
U2 - 10.1061/(ASCE)0733-9399(2000)126:1(17)
DO - 10.1061/(ASCE)0733-9399(2000)126:1(17)
M3 - Article
AN - SCOPUS:0034010957
SN - 0733-9399
VL - 126
SP - 17
EP - 26
JO - Journal of Engineering Mechanics
JF - Journal of Engineering Mechanics
IS - 1
ER -