Abstract： Viscous damper is one of the most widely used passive energy dissipation devices for cable-stayed bridge with floating system, however, the conventional parameter design method, which is far from efficiency and convenience, resorts to repeated nonlinear time history analysis. Therefore, based on the “pulse” characteristics of near-fault ground motions and the dynamic characteristics of cable-stayed bridge, the kinematic differential equations for a simplified two-mass model of cable-stayed bridge are established, and the calculation formulas for the dynamic response of girder displacement under the impact of near-fault pulse are derived. By using the equivalent linearization method, the relationship of nonlinear viscous damper parameters and equivalent damping ratio is achieved. Hence, the design parameters of viscous damper can be reversely determined by making use of the objective girder displacement of cable-stayed bridge. Finally, this simplified method is validated by a realistic case of cable-stayed bridge, and the flowchart for the simplified design method of viscous damper is also described.
