Experimental and Numerical Study of Low-Cycle Fatigue Performance of Bolted Drum-Shaped Spherical Shell Joints

Welded hollow ball joints are frequently utilized in spatial grid systems due to their straightforward structural design and obvious force characteristics, whereas bolted ball joints are frequently used for their ease of assembly and installation. Both hold a significant place in engineering practice. This research proposes a new type of joint node—the bolted drum-shaped spherical shell joint, which is suitable for grid structures. Based on the uniaxial mechanical performance test results of the joint, low-cycle fatigue tests were carried out, and the corresponding fatigue life curve was established, followed by a thorough evaluation of the fatigue life. Furthermore, a parametric analysis of the joints’ hysteretic behavior was performed by numerical simulations, and the seismic performance of bolted drum-shaped spherical shell joints with M20 bolts was evaluated under various influencing factors. The results of the investigation provide a theoretical basis for the application of this type of joint in practical engineering.