Seismic behavior of composite bolted T-shaped exterior joints in modular steel construction

This paper presents a new joint that is connected by common friction high-strength bolts and blind bolts. To study the seismic behavior of the proposed joint, four full-scale joints were tested by quasi-static tests and simulated by the finite element method. According to the stiffness, resistance and ductility of the joints, the influences of column-to-column blind bolt connection, beam-to-beam common bolted connection, and arrangement of inner diaphragm are analyzed. The results show that the beam-to-beam bolted connection, column-to-column blind bolted connection, and the arrangement of inner diaphragms can obviously improve the bearing capacity of the joints, which are 24.9%, 39.2% and 44.6%, respectively. The ductility of each joint is between 1.86 and 2.74, with an average value of 2.15. The joints with cover plate and inner diaphragm plate can meet the requirements of special moment frames (SMF). Therefore, the modular steel construction (MSC) in the seismic zone should adopt cover plate and inner diaphragm plate, and the joint should meet the requirements of strong column-to-weak beam to obtain better ductility.