1
Department of Civil Engineering,Amirkabir University of Technology
2
Department of Civil Engineering,Power and Water University of Technology
Abstract
Abstract. Performance based seismic design usually requires nonlinear dynamic or static analyses
to assess the performance level of the structure under seismic action. To trace the exact performance
point of a structure, these analyses should sometimes be repeated several times over. Analysis iterations
mainly depend on the initial design and performance of the structure. So, a method that can present
an appropriate initial selection with minimum time and e ort would be precious. Such a method would
also be very e ective for seismic structural assessment. In this paper, an intelligent system has been
created for the estimation of plastic hinge distribution and lateral ductility distribution and, also, for the
assessment of existing steel structures, based on a direct displacement based design procedure. The method
has been applied to the steel braced frames with concentric bracing systems in low, medium and high rise
buildings. The designer can use this knowledge based system to obtain the performance level of existing
steel structures, according to proposed seismic code levels. Finally, the intelligent system has been veri ed
using nonlinear dynamic analysis.
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