Shaking Table Tests of Rigid, Semirigid, and Flexible Steel Frames

A one-story, one-bay steel structure was constructed such that the beam-column connections could be changed from flexible to semirigid to rigid. Using a shaking table, structures with these three types of connections were subjected to base excitations with various intensities of records obtained from several past earthquakes. These studies indicated that the semirigidity of steel frames does not necessarily result in larger lateral drifts or in more damage than in the rigid frames. It was also observed that a well-proportioned semirigid connection designed to behave in a ductile manner can effectively participate in the nonlinear behavior of the structure, thus providing additional global structural ductility.