Akademik Veri Yönetim Sistemi
7th International Conference on Earthquake Engineering and Seismology, 7ICEES 2023, Antalya, Türkiye, 6 - 10 Kasım 2023, cilt.488 LNCE, ss.435-451
In engineering practice in Türkiye, there are three main codes employed for bridge design which are AASHTO LRFD Design Specifications for Bridge Design, Eurocodes and Turkish Earthquake Specification for Bridges. These codes have different seismic design criteria for the selection of ground motion records and design response spectra used in analysis. In this study, influence of ground motion scaling method on response of bridges is evaluated through linear time history analysis. For this purpose, three bridges representing short-, medium-, and long-period bridges are selected in Istanbul that lay near the Northern Anatolia Fault. Three scaling methods are employed to study the effect of scaling methods. The first method is to scale the ground motion records with one factor according to the mean spectrum of selected earthquakes. The second and third methods are to scale each ground motion record separately. No upper limits for the scale factors are introduced for the second method, while for the third method upper limit of 2 is assigned. Besides, to comprehend the importance of the selection of ground motion sets, three different sets, each having seven ground motion records, are formed. Analyses results like column moments and displacements under the selected and scaled ground motion sets are compared. The results indicated that the scaling methods and ground motion sets for the bridges having different fundamental periods do not have consistent results. It has been observed that, in general, the influence of ground motion set becomes insignificant as the period of the structure gets smaller. As a general conclusion, it appeared that no generalization can be made regarding the selection of a ground motion record set and scaling method for the studied bridges. It is suggested that various methods and ground motion sets should be employed to conduct a correct time history analysis and to meet the seismic demands of a specific structure.