Bridge damping's variable speed mass damper system

The utility model provides a bridge damping's variable speed mass damper system belongs to bridge structures and controls technical field passively. This variable speed mass damper system includes harmonious quality piece, gearbox, spring, energy dissipater and connecting piece can effectually reduce vertical displacement of the girder of earthquake power production to reduce cable tower's moment of flexure. Tip at the girder sets up horizontally connect spare, is connected with the gearbox on the anchorage, the gearbox is rack drive gear's speed change mechanism, set up vertical motion's harmonious quality piece in anchorage department, link to each other with the gear of gearbox with wire rope, the lower extreme coupling spring of harmonious quality piece to rubber energy dissipater is laid to bottom at quality piece slide. The kinetic energy that the girder obtained when the earthquake transmits for harmonious quality piece through the gearbox, and the gearbox can enlarge the speed of harmonious quality pi