assessment of seismic response of mid-rise steel buildings with structural configuration of framed tube skeletons

in this research, the performance abilities of tube type lateral load resistant framed systems are studied in order to assess the dynamic response of mid-rise steel structures subjected to both far and near-field earthquake records. for this purpose, four 10  story structural models with separated framed tube based skeletons were selected and designed. the structural models have been designed according to the iranian seismic code 2800  (third edition). the main criterion which was considered to select strong ground motions for performing nonlinear time history analysis is the existence of high amplitude and long period pulse or a multiple pulse feature in the velocity time history of each earthquake record. assessment of the analytical results should emphasize on the importance of both lateral displacement and drift of all stories which must be considered exactly during the design process. additionally, it was concluded that the maximum drift demand is about 0.035. the upper level of rotation of rigid connecting zones was calculated higher than seven percent of a radian. generally, it was concluded that, the seismic response of mid-rise steel structures with framed tube skeleton is dramatically influenced by those strong earthquake records which are able to display energized long period pulses in their time histories.