Abstract
As a passive control means to reduce traffic-induced vibration of viaducts caused by running vehicles, viscous dampers are studied. Complex eigenvalue analysis of a simple beam with two viscous dampers shows that high modal damping can be added to lower modes. An approximate formula for the modal damping ratio is derived. Through comparison with TMD and an active control method using simulation analysis, it was indicated that viscous dampers as well as the active control method are effective for traffic-induced girder vibration. However, it is also found that the three control methods considered here are not effective in reducing the dynamic reaction force in viaducts.
