NEHRP Clearinghouse

Linear Static and Dynamic Procedures for Structures with Velocity-Dependent Supplemental Dampers.
Sadek, F.; Mohraz, B.; Riley, M. A.
May 1999, 60 p.
Identifying Number(s)
The objectives of this study are: (1) to investigate the effect of increased viscous damping on the seismic response of structures; (2) to assess the accuracy of the linear static (LSP) and linear dynamic (LDP) procedures recommended in the NEHRP Guidelines for the Seismic Rehabilitation of Buildings (FEMA 273) for design of structures with velocity-dependent passive energy dissipation devices; and (3) to propose modifications to the current design procedures to improve their accuracy and reliability. The study also identifies the following limitations of the FEMA 273 procedures: (1) the use of a constant reduction factor for the displacement response of short-period structures; (2) the assumption of a harmonic response to compute the peak velocity; and (3) the computation of design forces based on the assumption that the structure undergoes a harmonic motion with an amplitude equal to the peak displacement and a frequency equal to that of the fundamental mode.
Passive systems; Static response; Earthquake resistance; Building codes; Design analysis; Performance evaluation; Dynamic structural analysis; Structural vibration; Vibration damping; Dampers; Structural response; Seismic effects; Degrees of freedom; Linearity; Energy dissipation