Wind-induced response control and serviceability improvement of an air traffic control tower

The results are presented of a serviceability study and vibration control techniques being employed for the air traffic control tower at Incheon International Airport (IIA) on Yongjong Island, Korea. Dynamic simulations, including wind-tunnel tests, revealed that passive damping devices such as tuned mass dampers were not sufficient to satisfy the serviceability criteria and that the use of active damping systems would be necessary. Therefore, a hybrid mass damper (HMD), which was eventually adopted for use in the tower, was proposed as a damping device in order to mitigate wind-induced responses of the tower while maintaining its original design for functional and architectural aesthetic reasons. In active control of the tower, the H_∞ control method with a bilinear transform was proposed to obtain optimum efficiency under the limitation of damper stroke. The relationship between the target damping ratio and the stroke is investigated with the optimally designed controllers by the proposed method. Numerical simulations show that the optimally designed HMD system would be expected to reduce the wind-induced vibration effectively and to satisfy serviceability criteria as well as other design constraints. After the installation of the HMD system, free vibration tests have been conducted and the results are presented.