Abstract
Reducing the aerodynamic forces of the cables has been a main concern for the design of long cable-stayed bridges. This research investigated the effects of surface modifications, which are the aerodynamic countermeasure against rain-wind-induced vibration, on the aerodynamic forces of and the flow field around cables through wind tunnel tests. According to the measurements of aerodynamic forces and surface pressure, the drag and fluctuating lift coefficients of the spiral protuberance and indent cables were smaller than those of the normal circular cylinder, accompanied by the delay in the flow separation and the recovery of the base pressure. According to Particle Image Velocimetry (PIV) test and Proper Orthogonal Decomposition (POD) analysis, the discretely distributed indent and spiral protuberance increased the surface roughness and suppressed the Kármán vortex shedding, subsequently reducing the wake width and the drag force.
