The effect of semi-rigid steel connections to seismic behavior of high-rise buildings

Tall steel structures have always been at risk from fire, explosions and natural disaster, especially earthquakes. It is seen in recent researches, although it is assumed that the seismic performance of steel structures is more efficient that reinforced concrete ones, especially after 1994 Northridge earthquake, considerable deformations and damages have been realized by reason of deficiency of connection details. Therefore,when designing tall buildings,behaviour of steel connections under seismic scenarios have to be investigated more deeply with the purpose of decreasing damages and casualities. İn the meantime, it is crucial that attaching importance to nonlinear time history analysis, which is being popular in recent years. Within the scope of this study, the performance of fully rigid and semi-rigid connected tall steel frames are investigated under ground accelerations. Apart from moment connections simple and shear connections are modified with component method to get a better understanding of the behavior in lateral resisting system. 7 real ground motions are used in dynamic analyses after scaling the datas according to provided design spectrum which is identified in Turkish earthquake code DBYBHY-2007. As a result of performing analyses, limit controls are checked and performance of the system with modified connections is compared with traditionally connected system. To have an opinion about the efficiency, story drift ratios and base shear of both systems are searched.