Seismic performance of semi-rigid steel frames

Experimental results indicate that many connections in steel frames show semi-rigid behaviour. There is a great deal of data on the performance of different types of connections in the literature, but the dynamic response of these frames has not received much attention. The objective of this study is to investigate the seismic behaviour of two-storey semi-rigid frames through the pseudo-dynamic testing. Analytical models for analyzing these frames are discussed. In order to investigate the influence of the dynamic characteristics of the frames and time history records, a number of frames with different configurations are subjected to five earthquake records. In this study, the behaviour factors of partial strength semi-rigid steel frames are evaluated and the dynamic response of these frames. are compared with both rigid and full strength semi-rigid frames. It is shown from experimental and analytical investigations that the semi-rigid steel frames represented good performance for ground motions and attracted less storey shear forces than rigid one. By virtue of the elongated period of vibration and energy dissipation in connections, the response of the partial strength semi-rigid frame as a whole is well below its rigid counterpart.