Investigation of seismic isolation efficiency for building structures

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. 


Derivation of site-specific UHS based on simulated ground motions and its parametric effects on building fragility
Azari Sisi, Aida; Askan Gündoğan, Ayşegül; Department of Civil Engineering (2016)
Estimation of seismic demands is essential for the purpose of structural seismic design and analyses. It is significant to obtain reliable ground motion amplitudes to estimate seismic damage on structures in a realistic manner. The ground motion simulation methodologies provide a physical approach to estimate seismic demands in the regions with sparse recording data and scarce networks. This dissertation consists of two main parts: In the first part, site-specific uniform hazard spectrum (UHS) of Erzincan r...
Ground motion prediction equations based on simulated ground motions
Gür, Kader; Askan Gündoğan, Ayşegül; Kale, Özkan; Department of Earthquake Studies (2018)
Ground Motion Prediction Equations (GMPEs) are one of the key elements in seismic hazard assessment to estimate ground motion intensity measures by basically taking into account source, path and site effects. Most of the existing predictive models are derived from databases compiled from real (or observed) ground motion data. However, in data-poor regions, a novel practice to develop new GMPEs is to use simulated or hybrid ground motion datasets for performing reliable seismic hazard analysis. Simulations o...
Probabilistic methods for estimating the seismic deformations of underground structures
Soyman, Kadir Buğra; Gülerce, Zeynep; Department of Civil Engineering (2018)
In seismic design of underground structures, simplified semi-deterministic methods based on the stiffness of the soil and the underground structure are used to estimate the seismic deformations. Generally, peak ground acceleration (PGA) value for different hazard levels are provided by the probabilistic seismic hazard assessment (PSHA) analysis, but a single (and deterministic) PGA value is employed in deformation calculations. The objective of this study is to propose a fully probabilistic framework for es...
Torsional hysteretic damper for seismic protection of structures
Salem Milani, Ali; Dicleli, Murat; Department of Engineering Sciences (2014)
During the past decades, use of supplementary systems for seismic control of structures has gained increasing acceptance, and research has flourished on development and performance characterization of such systems. These include isolation systems and energy dissipation devices (dampers). This study is devoted to development of a new hysteretic damper for seismic protection of structures. The new system is a stand-alone damper, named Multi-directional Torsional Hysteretic Damper (MTHD). MTHD is composed of e...
Analytical prediction of thermal displacement capacity of integral bridges built on sand
Dicleli, Murat (SAGE Publications, 2005-02-01)
In this research, analytical equations are developed to calculate the lateral displacement capacity and maximum length limits of integral bridges built on sand based on the low-cycle fatigue performance of the piles under cyclic thermal variations and the ultimate strength of the abutment under positive thermal variations. To formulate the displacement capacity and maximum length limits of integral bridges based on the low cycle fatigue performance of steel H-piles under cyclic thermal variations, first, H-...
Citation Formats
S. Özdemir, “Investigation of seismic isolation efficiency for building structures,” M.S. - Master of Science, Middle East Technical University, 2016.