A review of cases of vortex shedding excitation in bridges : Sectional models testing

Vortex shedding excitation frequently occurs in cable supported bridges. Even other types of bridges such as beam or arch bridges suffer this phenomenon during or after construction. It is well-known that a bluff body sheds alternating vortices with frequency n, which mainly depends on the Reynolds number and body geometry. Vortices induce transverse forces on the body with the same frequency. In many cases of flexible and slender structures with a small damping, these forces may produce unacceptable vibrations. This paper reviews several bridges where this phenomenon was important and explains the approaches used to study the instability and the solutions to improve the behavior of the structures. Then several sectional models of long span bridges have been tested in the wind tunnel of the School of Civil Engineering at the University of La Coruña for the vortex shedding excitation.