Comparison of design codes for seismically isolated structures

Acar, Emre
This study presents information on the design procedure of seismic base isolation systems. Analysis of the seismic responses of isolated structures, which is oriented to give a clear understanding of the effect of base isolation on the nature of the structure; and discussion of various isolator types are involved in this work. Seismic isolation consists essentially of the installation of mechanisms, which decouple the structure, and its contents, from potentially damaging earthquake induced ground motions. This decoupling is achieved by increasing the horizontal flexibility of the system, together with providing appropriate damping. The isolator increases the natural period of the overall structure and hence decreases its acceleration response to earthquake-generated vibrations. This increase in period,together with damping, can reduce the effect of the earthquakes, so that smaller loads and deformations are imposed on the structure and its components. The key references that are used in this study are the related chapters of FEMA and IBC2000 codes for seismic isolated structures. In this work, these codes are used for the design examples of elastomeric bearings. Furthermore, the internal forces develop in the superstructure during a ground motion is determined; and the different approaches defined by the codes towards the ءscaling factor̕ concept is compared in this perspective.


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This thesis analyzes the performance of structural timber and steel in medium and long span roof structures. A technical background about roof structures including structural elements and roof structure types, span definitions, and classification of roof structures are discussed. Roof structures are detailed with traditional and the contemporary forms. The thesis comprises the comparison between structural timber and steel by using structural, constructional and material properties. Structural forms and the...
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Dicleli, Murat (American Society of Civil Engineers (ASCE), 2002-03-01)
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Some observations on the seismic behaviour of traditional timber structures in Turkey
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Use of simulated ground motions for the evaluation of energy response of simple structural systems
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The literature on energy-based seismic design and assessment methodologies of structural systems mostly relies on real ground motion datasets. However, certain bias exists due to lack of homogeneity in available ground motion datasets. In this study, a large set of ground motions is simulated. Next, the effects of various parameters on seismic behavior of SDOF systems in terms of energy are studied using nonlinear time history analyses. The stochastic finite-fault simulations are performed on the western pa...
Citation Formats
E. Acar, “Comparison of design codes for seismically isolated structures,” M.S. - Master of Science, Middle East Technical University, 2005.