Seismic performance of high-rise building frames with added energy-absorbing devices

The concept behind passive vibration control is to add energy dissipating devices to a structure so that energy dissipation can be primarily constrained to the designed location of these passive control devices instead of the main load-carrying members. Since these passive control devices are separated from the main structures, they can be easily replaced if extensively damaged. The use of these energy-absorbing devices to dissipate the seismically induced energy is one of the most economical and effective ways to mitigate the effects of earthquakes on structures.; The dissertation is concerned with a study of two different devices, a combination of tapered-plate energy absorber (TPEA) and viscoelastic dampers and a combination of TPEA and fluid dampers. It starts with a general review of the developments in various energy dissipating devices. Then a finite element formulation for fluid dampers is developed for this study. A comparison is made between numerical solutions and experimental results when a 2/5 scale steel structure is equipped with added viscoelastic dampers. The structural response of high-rise buildings mounted with three energy-absorbing devices, tapered-plate energy absorber (TPEA), viscoelastic dampers, fluid dampers, and two combined devices which are a combination of TPEA and fluid dampers and a combination of TPEA and viscoelastic dampers, respectively, have been investigated. Next, a parametric study of TPEA devices for high-rise buildings is conducted. The selected response parameters in this study include: (1) story shear force; (2) floor displacement; (3) base shear force and (4) ductility ratio.; Finally, two combined devices, a combination of TPEA and viscoelastic dampers and a combination of TPEA and fluid dampers are examined. Results show such combined devices provide a strong safe-failure mechanism as reliable energy absorbing devices. They also can sustain a wide range of loadings from minor to severe earthquake ground motion and wind loads. The combined devices can compensate for each other's shortcomings so that a satisfactory design for wind loads and seismic hazard mitigation of the structures can be achieved.