A DEVICE FOR SUPPRESSING WAKE GALLOPING OF STAY-CABLES FOR CABLE-STAYED BRIDGES

An experimental study of wake galloping of a pair of parallel stay-cab les for cable-stayed bridges was conducted in two wind tunnels to deve lop a new device for suppressing the instability. In its early stage, the following device was examined: A pair of parallel cables is connec ted rigidly to each other with spacers so that the cables form a SINGL E MEMBER with or without a GAP between the cables. It was determined f rom the tests that the member without a gap is stable for all wind ang les of attack with the exception being around 5 deg. Based on the expe rimental results, an alternative device was developed consisting of a pair of cables stranded helically. The strand was found to be stabiliz ed aerodynamically as only a small portion of the cables is exposed to the unstable wind angles of attack around 5 deg.