Seismic Performance of Tubular Square Column to Stiffened I-Beam

This paper investigates the behaviour of welded steel I-beams to hollow square tubular columns. Six finite element stiffened models of welded steel connections, with the same designs, are exposed to cyclic loads and verified against the experimental results of unstiffened model obtained from previous researches and current design guides. During the testing, the connections' flexibility and strength are assessed, and damage phenomena and failure modes are investigated. The connection damage is discovered to be a cumulative fracture process that leads to significant gradual degradation of the connection's mechanical capabilities. Quantificational analyses of cyclic loading induced damage are also carried out in order to investigate the level of connection damage based on different loading intensities. A numerical investigation of finite element modelling is also carried out to validate the experimental results, and a satisfactory agreement is obtained. The test results and FE modelling give benchmark data for unstiffened and stiffened welded connections, where the results show that using proper stiffener configuration affects the stress distribution through the connection and increases the ultimate moment of the connections