95-0002 Experimental & Analytical Study of Low-Cycle Fatigue Behavior of Semi-Rigid Top-and-Seat Angle Connections G.Pekcan, J.B.Mander, S.S.Chen 1995 University at Buffalo 136 PB95-220042 15 One common type of existing structure is the steel frame with semi-rigid connections. In previous studies, analytical models have been developed, the effects of floor slabs and masonry infills have been studied, and parametric response analyses have been performed. This report summarizes work on the low-cycle fatigue behavior of a common type of semi-rigid connection, those made of top and seat angles. Nineteen tests were performed using various load histories and they showed that the hysteretic energy-life and rotation-life models are applicable for this type of connection. The analysis showed that if the plastic hinge rotations are kept below 2%, the connections can sustain at least fifty cycles of complete load reversals. The report contains a valuable database on the cyclic behavior of one type of semi-rigid connection.<BR> Steel Frames, Semi-Rigid Connections, Top Angles, Seat Angles, Low Cycle Fatigue, Cyclic Energy Dissipation, Drift Reversal, Damage Accumulation, and Plastic Connection Rotation.