STRUCTURE AND INFRASTRUCTURE ENGINEERING, cilt.13, ss.1002-1012, 2017 (SCI-Expanded)
Bridges in Turkey have been designed using a modified version of AASHTO Load Factor Design Specifications. In this paper, a new design spectrum is being analysed to address the characteristics of the Turkish earthquake records. The main contribution of this study is to suggest a mean Turkish site-dependent response spectra especially for the constant velocity region by analysing a number of Turkish earthquake records. The findings are compared to the two different design spectra of AASHTO. The mean site-dependent response spectra normalised with the peak ground accelerations are analysed for certain soil conditions and for a given range of moment magnitude values. The mean site-dependent response spectra corresponding to the largest moment magnitude range is observed to lie above the design spectra for periods larger than 1.0 s. Response spectrum analyses and time history analyses are performed on selected bridges using AASHTO design spectra and the mean site-dependent response spectra to observe the differences in corresponding structural responses. Results from analyses indicate that design spectrum is conservative for small to moderate moment magnitude levels. However, for the largest moment magnitude range considered, structural responses from mean site-dependent spectra are higher than those obtained from the design spectra.