SEISMIC EVALUATION OF STEEL DUAL SYSTEM S AGAINST AR TIFICIAL EARTHQUAKES

Dual systems in form of steel moment frames accompanied with chevr on bracings are among commonly used systems in high sei smicity regions in the world. Therefore, the rec ognition of their seismic behaviour is of high importance. E xcept a few parts of the world that have sufficient earthquake records, artificial accelerograms can be used in other regions. One method for generating ar tificial accelerograms is using wavelet transform. In this pap er, 5-, 10-, 15- and 20-story structures are desig ned according to ASCE7 requirements. Spectra matching pro cess is performed for 44 earthquake records. Pus hover and nonlinear time history analysis is done in order to investigate seismic behaviour of this system against real and artificial earthquake records. It can be conclu ded that responses against artificial records has f ar less dispersion, while the average responses in these two sets of records are approximately the same.Incre mental dynamic analysis is done, and adjusted collapse mar gin ratios are calculated, in order to check whether frames can meet the FEMA-P695 criterion. Fragility c urves are obtained to know the probability of collapse for these earthquakes.

Keywords:

Dual System , Chevron B races , IDA , Artificial Accelerogram , Wavelet Transform