In this thesis, we address the seismic analysis of a three-story reinforced concrete frame
building, i.e. SPEAR building, and the seismic analyses for two variants of the seismically
isolated SPEAR building, where either elastomeric or frictional seismic isolators are used. First,
we discuss the theory of seismic isolation of structures and the equations that describe the
dynamic properties of a seismically isolated building using a two-degree-of-freedom (2DOF)
model, which includes seismic isolation and the building structure. We then present the
requirements for the use of anti-seismic devices in accordance with the new version of
Eurocode 8 and the application of the new elastic response spectrum. Furthermore, we
introduce the SPEAR building and some types of seismic isolators, two of which are used for
the seismic analysis of the seismically isolated versions of the SPEAR building. Additionally,
we analyze the circular frequencies for the first mode of vibration of the 2DOF system
depending on the properties of the seismic isolators and considering the requirements of
Eurocode 8. Finally, we conduct a seismic analysis of all variants of the SPEAR building and
compare the seismic demands on the building structure. We find that the seismic demand on
the seismic isolators is within the allowable limits, while the seismic demand on the structural
elements for the seismically isolated versions of the SPEAR building is significantly lower
compared to the non-isolated building. The reduction of seismic demand on the structure is
due to the lengthening of the period of vibration, with an additional reduction in the seismic
demand due to the energy dissipation in the seismic isolators. The torsional vibration of the
building is also reduced. The building vibrates almost as a rigid body, which was not the case
with the original SPEAR building.
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