List of Articles میراگرهای ویسکوز

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  1 - Seismic Behavior Upgrade of Steel Moment FramesUsing Viscous Dampers and Determination of Their Proper Damping Forces
  seyyed Mehdi Zahraei Omid Mohammadi
  Energy dissipation systems have been broadly used in structures during the recent decades in order to reduce earthquake and wind forces as well as reduction of structural lateral drifts within the code limits. Viscous damper is considered as one of the energy dissipatio More

  Energy dissipation systems have been broadly used in structures during the recent decades in order to reduce earthquake and wind forces as well as reduction of structural lateral drifts within the code limits. Viscous damper is considered as one of the energy dissipation systems which are classified as velocity-dependent dampers among passive control systems and have been paid attention and their further detailed properties taken into account by many researchers. Viscous damper consists of a piston with some orifices inside the cylinder which contains highly viscous fluid. Energy dissipation of this damper is through pushing viscous fluid out of the orifices. These are two types of these dampers: linear and nonlinear from which linear type with velocity power of one is more practical. The structural damping force is usually set according to the procedure described in FEMA273 and are optimized by three controlled modes of displacement, velocity and acceleration. This study examines the effect of adding viscous dampers on seismic behavior of steel moment frames. For this purpose, three steel moment frames of 1, 3 and 6-story all in 3 bays, with viscous dampers having power factor of 1, 0.8 and 0.6 are selected. These sample structures are subjected to the nonlinear time history analysis under the El Centro, Kobe and Northridge earthquakes, and their response including displacement, acceleration and base shear is compared in two cases of with and without viscous dampers. Finally, regarding nonlinear time history analysis results based on the structural behavior in three modes controlled by displacement, velocity and acceleration, proper damping forces are specified as 94.7, 240.1 and 557.1 kN respectively for one, three and six story structures based on maximum acceleration and base share obtained from FEMA273. Manuscript profile
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  2 - The Effect of Viscous Dampers in Seismic Retrofitting of Steel Buildings
  Mehdi Vakilzadeh Kambiz Mazaheri Mohaddeseh Bakhtiyari Azad
  The target of seismic improvement of a building is to strengthen the structural and non-structural members in order to reduce the earthquake damage. Dampers dissipate the structure’s energy.By using these types ofequipment,the damage to the structure is dramatical More

  The target of seismic improvement of a building is to strengthen the structural and non-structural members in order to reduce the earthquake damage. Dampers dissipate the structure’s energy.By using these types ofequipment,the damage to the structure is dramatically reduced. In this article steel frames with three, six and ten stories with and withoutdampers aremodeled in SAP software.They are evaluated by using seismic retrofitting guidelinesand nonlinear static method. The results show that adding a viscous damper reduces seismic effect and damage performancelevel.In addition, using dampersin high-rise structures is more effective than shorter ones in reducing the effects of an earthquake. Manuscript profile