Investigation of seismic isolation efficiency for building structures

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2016
Özdemir, Seda
The main goal of this study is to assess the efficacy of seismic isolation for building type of structures with different structural systems, namely, dual systems and moment frame systems having also different number of floors. Specific to this study, the main parameters employed for efficacy assessment will be the interstorey drift ratio and floor acceleration since both structural and non-structural damage to be occured in a system are directly related to these two parameters. To assess the variations in interstorey drift ratio and floor accelerations between different structural systems, linear elastic response spectrum analysis procedures are followed for two different site-specific seismicity levels representing two site regions from Izmir and Isparta, respectively. To enhance the accuracy of the response, seismically isolated dual systems having different number of floors are analyzed non-linearly in modal space under the seismicity level of Izmir, since for non-structural content, floor acceleration value that the structure undergoes has a special importance when the content of a building constitutes of valuable acceleration-sensitive equipments. The analyses performed in this thesis work indicated that for both type of structural systems, by the application of seismic isolation design method,the efficiency of reduction in interstorey drift and floor acceleration decreases as the number of floor increases. In addition, the amount of efficiency differ from each other between dual systems and moment frame systems. Another major conclusion is that linear elastic analysis procedures may underestimate both floor acceleration and interstorey drift responses. 

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Citation Formats
S. Özdemir, “Investigation of seismic isolation efficiency for building structures,” M.S. - Master of Science, Middle East Technical University, 2016.