Reviewing the art of modeling 3D aeroelastic behavior of cable-stayed bridges

Abstract

The development of an optimized structural design and the calculation of dynamic internal forces in the complete structure of a cable-stayed bridge under wind action is properly carried out with a theoretical-computational 3D aeroelastic model. The mathematical model of the applied aerodynamic forces is formulated by taking into account the aerodynamic and aeroelastic coefficients obtained through wind tunnel tests of small scale seccional models. Physical 3D aeroelastic modeling of very long cable-stayed bridges requires very large wind tunnel facilities and it is usually time and cost prohibitive. Hence for the design of these bridges the 3D theoretical – computational model offers some practical advantages. However it needs to be validated by sound correlation of numerical results with their experimental counterpart obtained from measurements on the actual structure or more easily on its 3D physical model tested in the wind tunnel where distinct wind characteristics can be well simulated. This paper explores these technical and practical aspects and focus on the validation of the 3D theoretical model against data collected from wind tunnel tests on a 3D physical model carefully constructed in a geometric scale that can fit inside ordinary small wind tunnels.