Influence of viscous dampers ultimate capacity on the seismic reliability of building structures

Anti-seismic devices should be designed with proper safety margins against their failure, because the reliability of structural system where they are installed is strongly influenced by reliability. Seismic Standards generally prescribe factors (reliability factors) amplifying device responses at design condition, in order to reach a target level. In case Fluid Viscous Dampers (FVDs), these applied stroke and velocity, values not homogeneous among seismic codes. This paper investigates influence for FVDs on systems equipped them. An advanced FVD model employed account impact forces arising when dampers end-stroke brittle failure due attainment maximum force capacity. The effect damper both fragility risk investigated performing multiple-stripe analysis monitoring different global local demand parameters. particular, parametric study has been carried out, considering two studies consisting low-rise medium-rise steel building, coupled dissipative linear nonlinear properties studying consequences forces. results give evidence potential behaviour provide information about relationships between effective Some preliminary suggestions given possible improvements current approaches considered future code revision.