A study on stabilizing mechanism of flap countermeasures mitigating VIV of a box girder bridge section

Abstract As bridge spans stretch, the structure becomes more flexible and susceptible to dynamic wind effects causing harmful wind-induced vibration. The biggest issue with design of long-span bridges is possibility vibration caused by vortices. This study examines mechanism decrease in amplitude vortex-induced for box girder using a flap countermeasure. Aerodynamic countermeasures such as have successfully increased deck aerodynamic stability. However, their stabilizing has yet be fully understood. Based on proposed approach, tunnel experiment CFD technique are used investigate instability presence countermeasures. flow fields surrounding deck, both without flap, examined, outcomes compared. Flow imagery utilized explain understand modified properties that minimize amplitude. Indeed, installing flaps leads turbulence over surface at leeward side, which disrupts vortex formation decreases lift forces structure. In addition, results revealed efficiency related installed location length. research provides reliable framework designing countermeasure significantly improves stability deck-flap system.