Field measurement of damping in industrial chimneys and towers

In the design of industrial chimneys and towers, structural engineers must assume a level of the inherent damping in the structures. In order to bette r estimate the dynamic response of those structures, actual damping was mea sured from wind-induced vibration signals of chimneys and towers and its ch aracteristics with respect to the response levels, the structural systems, and the wind direction were discussed. Damping ratio and natural frequency for three chimneys and two towers were calculated using random decrement te chnique.