Experimental and numerical study on hysteretic performance of aluminum alloy weak-axis beam-to-column joint connected by ring-groove rivets

This study experimentally and numerically investigates the hysteretic behavior of aluminum alloy weak-axis joints connected by ring-groove rivets. Two full-scale cruciform joint specimens were tested, incorporating stainless steel side plate connections with different configurations, aluminum alloy I-shaped beams, and aluminum alloy I-shaped columns. The test results elucidate the failure modes, hysteresis response, strain distribution, and key performance indicators of the weak-axis joints. A comparative analysis was conducted between weak-axis and strong-axis beam-to-column joints. Finite element models were developed and validated to perform subsequent parametric analyses. The results demonstrate that: (1) The proposed weak-axis beam-to-column joints exhibit excellent ductility, with an ultimate drift ratio up to 8%, satisfying major seismic code requirements. (2) Panel zone shear deformation is negligible, and failure is governed by cover plate cracking and pin shear, both displaying ductile characteristics. (3) Although the initial stiffness is about 40% lower than that of strong-axis T-stub beam-to-column joints, the load capacity is approximately 25% higher. (4) Parametric analysis reveals that increasing the friction coefficient or cover plate thickness enhances post-slip performance, while the column axial compression ratio has a negligible effect; side plate material strength is more influential than beam and column material strength.