Phänomenologie und Modellierung Regen-Wind induzierter Schwingungen

Regarding cable stayed bridges the simultaneous appearance of rain and wind may induce cable oscillations with large amplitudes. First, the fluid-mechanical reason for these phenomena is represented by means of which a mechanical model is deduced. Rain-wind induced vibrations exist only within a certain range of wind velocity. The lower limit of the critical velocity range is calculated for various cable inclinations and angles of incidence. A fluid mechanical interpretation is given for the existence of the upper limit. The approximation of the limit velocities and the determination of critical diameters results from simplied fluid-mechanical correlations. Furthermore the numerical investigation shows that Rain-wind induced oscillations occur also on vertical cables. Considering the Faro-Falster Bridge as example, the numerical vibration analysis is carried out for the cables parallel and perpendicular to the wind direction.