Galloping of cables with moving rivulet

There have been many reports recently on excessive and unanticipated vibration of cables in cable-supported bridges under the simultaneous occurrence of wind and rain. Correspondingly, many efforts have been made to avoid such large amplitude cable vibrations which often cause fatigue damage and corrosion to strands in surprisingly short periods. However, the mechanism of wind-rain-induced cable vibration is still not clear and no analytical solution is available for the design of cables. This paper thus presents a preliminary theoretical study, aiming to explain some phenomena of wind-rain-induced cable vibration observed from field measurements or wind-rain tunnel. tests and to provide an analytical solution to the problem. The one-degree-of-freedom galloping theory is applied to wind-excited cables with moving rivulet. The interaction between wind, cable, and rivulet is taken into consideration. After the equation of motion of the wind-excited cable with moving rivulet is derived, extensive parametric studies are performed. The achieved results are very promising compared with the observations from the field and wind-rain tunnel tests.