Rain-wind induced vibrations of cables stayed bridges

Abstract In the period of construction of a cable stayed bridge, large amplitude vibrations of cables were observed under rain and wind conditions for several times. The results of full scale measurement confirmed that the vibration is a new type of instability phenomenon which is caused by the combined influences of rain and wind. Based on the wind tunnel test with reproduced rain condition, it is shown that the rain influence is originated by a rain water rivulet formation along the upper windward surface of cable, and with this rivulet formation, an apparent cable cross section becomes aerodynamically unstable.