EFFECT OF BEAM SIZE ON LOW-CYCLE FATIGUE PERFORMANCE OF STEEL BEAM-END CONNECTIONS

In the seismic design of steel moment resisting frames, large structural members, particularly H-shaped beams with substantial flange thickness, are commonly utilized in high-rise steel buildings to enhance seismic resilience. However, the influence of dimensional variations on the low-cycle fatigue performance of steel beam-end connections remains inadequately clarified. This research investigates this phenomenon through a series of constant amplitude cyclic loading tests on full-scale T-shaped beam-to-column connection specimens, with beam flange thicknesses ranging up to 50mm. The results indicate that the number of cycles to fracture of the connection decreases with increasing specimen size and loading amplitude.