Parameter Optimization of Fluid Viscous Damper Based on Stochastic Vibration

In order to avoid the large computational cost and low efficiency of parametric-sensitivity methods in the parameter optimization of fluid viscous dampers, the theoretical optimum damping ratio of the bridge superstructure vibration system was derived by stochastic vibration method, and an analytical expression for the optimum damping coefficient of linear fluid viscous damper for bridge was then obtained. Meanwhile, the optimum damping coefficient of nonlinear fluid viscous damper for bridge was also derived based on the principle of energy equivalence. In order to verify the reliability of the analytical expression, taking a continuous bridge as an example, the parametric sensitivity on the damping coefficient was analyzed by dynamic time history method. The results show that the theoretical optimum damping ratio of the bridge linear fluid viscous damper is 0.5, which enables the damper to reach its maximum frequency. Compared with the linear fluid viscous damper, the optimum damping coefficient and damping force of the nonlinear fluid viscous damper is decreased by 55% -67% and 16% -22%, respectively.