PURPOSE: To enable the oscillation of a bridge to be effectively damped even if the bridge is built on poor subsoil, by placing response controllers between footings constructed on ground and bridge legs for supporting a bridge grinder, to arrange dampers on the side surfaces of the bridge legs, and by contriving the oscillation of the ground not to be transmitted to the bridge girder.

CONSTITUTION: Between footings 5 constructed on foundation piles 9 set vertically to ground 4, and bridge legs 3 for supporting a bridge girder 2, response controllers 6 are placed, and between the lower end section side surfaces of the bridge legs 3 and the footings 5, dampers 7 are arranged. Then, oscillation energy in the horizontal direction, generated on the ground 4, due to earthquake or the like is absorbed by the dampers 7, and a shearing force is bumped by the oscillation suppressors 6, and the oscillation of the ground 4 is contrived not to be transmitted to the bridge girder 2. As a result, even if the bridge is built on poor subsoil, the oscillation of the bridge girder can be effectively damped.