Viscoelastic dampers typically introduce both stiffness and damping into a building frame,and thus the design of a energy dissipation system added viscoelastic dampers is more complex than a system added viscous dampers.In this paper,a modal equation of motion will be expressed into state space equation,and then a Lyapunov function is constructed.Assumed seismic response of a structure is random response,a calculation formula of additional equivalent damping ratio for viscoelastic dampers is derived.Energy dissipation characteristic of viscoelastic dampers can be expressed by the damping ratio...
