Seismic behaviour of an earthquake-resilient prefabricated beam-column cross joint

Abstract

Earthquake-resilient structures have become a hot topic in seismic research. Based on the concept of damage control, this paper presents a new type of earthquake-resilient prefabricated beam-column cross joint (ERPCJ). After a strong earthquake, the function of the joint can be quickly restored because damage is concentrated mainly on replaceable connecting parts. First, the construction and advantages of the ERPCJ are explained, and its seismic design requirements are established. Then, the theory behind the design of the ERPCJ is proposed and verified by numerical simulation using eight ERPCJ models. The hysteretic behaviour of the ERPCJ was investigated using the finite element (FE) method considering the effects of the weakening profile in the flange cover plate, the thickness and strength of the flange cover plate, the distance between the middle bolts, the gap between the beams, and the bolt hole shape. Finally, cyclic loading and repairing tests were conducted on a basic specimen, and the rationality of the design theory was verified. The seismic performance and the post-earthquake resilience performance of the joint were investigated. Numerical analysis and experiments showed that the proposed design theory could accurately predict the yield load of the ERPCJ. A reasonably well-designed ERPCJ should have good bearing capacity, collapse resistance capacity, seismic performance, and post-earthquake resilience performance. The thickness and strength of the flange cover plate, the distance between the middle bolts, and the gap between the beams have a large effect on the seismic behaviour of the joint, and so should be properly designed.