FInite Element Analysis of the Hysteretic Behavior of Aluminum Alloy Beam-Column Joints After High-Temperature Exposure

In order to study the hysteretic behavior of aluminum alloy T-shaped beam-column joints after exposure to high temperatures， the stress and deformation mechanisms of T-shaped beam-column joints were analyzed by comparing quasi-static loading tests with ABAQUS finite element simulations， and a parametric finite element parameter analysis was carried out. The results showed that the finite element model accurately simulated the test process. When the joint was subjected to high temperatures of 450 ℃， 300 ℃， 150 ℃， and room temperature， the failure mode was brittle fracture. Hysteresis curves were pinched due to bolt slip. Increasing the thickness of the T-stub gusset plate reduced the stress concentration at the corner of the gusset plate， and the failure mode of the joint shifted to the deformation failure of the hole at the beam end. Increasing the number of gusset plate bolts mitigated the decrease in the bearing capacity of the joint caused by sliding and improved the bearing capacity of the joint during the middle and late stages of loading. At normal temperature， increasing the thickness of gusset plate prevented brittle fracture of the joint. The joint that experienced a maximum temperature of up to 150 ℃ exhibited seismic performance similar to that at room temperature. With the increase of temperature， the allowable axial compression ratio range of the joint gradually decreased， and the failure mode of the joint shifted to early buckling failure of the column. After the maximum temperature exceeded 150 ℃， the ductility of the beam-column joint increased while the bearing capacity decreased， necessitating additional reinforcement.