Comparison of Design Spectra in Turkish Earthquake Codes (TEC and TBEC) in Terms of Seismic Isolator Design

Abstract

In this study, for a seismically isolated structural model designed in accordance with the design spectra defined by both Turkish Earthquake Codes 2007 and 2018, variation of maximum isolator displacement was studied. The isolation system in the structure was composed of lead rubber bearings. Selected and scaled ground motion records were used to perform bi-directional analyses where both horizontal components of records were subjected to analytical model, simultaneously. Analyses were repeated for both deteriorating and non-deteriorating hysteretic representations of isolators. Considered parameters were Q/W ratio of the isolator and the construction site. Results showed that analyses based on design spectra of different versions of Turkish Earthquake Code may lead to variation in maximum isolator displacements up to 50% depending on the coordinate of the structure. It is also observed that use of deteriorating hysteretic representation for seismic isolators will result in even higher variations in maximum isolator displacements.