The Analysis Of Flutter Performance Of Truss Suspension Bridge

With modern structure to span a larger, more flexible, more delicate direction of the development of bridge, flutter stability has become a key issue to wind resistance design. This will be the main span of 536m Liujiaxia flutter stability of the bridge as an background to study the truss section of the flutter chatter and improve the critical flutter wind speed of effective measures.Based on two degrees of freedom coupled flutter theory, this paper writes computer programs to calculate the critical flutter wind speed of the section model, and used two examples to verify the accuracy of the program. Through the truss section model wind tunnel tests and programming calculation, found the original truss sections can not meet the flutter stability requirements. Then through a series of aerodynamic measures and damping measures to improve the truss section of the flutter critical wind speed, it showed that certain aerodynamic measures to additional stability of the upper and lower plats are effective measures for improving the flutter stability. Also in the increase of damping measures simply to reverse the torsional damping ratio is a more effective measure. Finally, based on two degrees of freedom coupled two-dimensional flutter theory, for the truss section and its various measures and damping measure aerodynamic flutter analysis of a simple mechanism, found that changing the aerodynamic measures will enable the truss section of the flutter stability of a qualitative change, and damping measures to change the mechanism from the point of view chatter chatter stability only to a volume change occurred..