RIAHI - PhD Candidate, Department of Civil Engineering, Sharif University of Technology, Tehran
ESTEKANCHI - Associate Professor, Department of Civil Engineering, Sharif University of Technology, Tehran

Limitations in the existing ground motion database force the scaling of real records to obtain accelerograms that are consistent with the ground motion target for structural design and evaluation. Usually the processes of selecting earthquake ground motions and their scaling to match the design spectrum are separate and distinct. Several methods of scaling time histories have been proposed. These include frequency-domain methods and time-domain methods. In the seismology and engineering communities the acceptance of the limits for legitimacy of scaling varies a lot. In this study different methods of scaling time histories are compared. A set of ground motion is selected and scaled with different methods to match the target response spectrum. Scaling factors obtained from different methods are compared. A new method for selecting and scaling records is introduced. The biases in the resulting nonlinear structural response, introduced by scaling of earthquake records, are compared in different scaling methods.