Monotonic loading performance of GFRP beam-column joints connected with slotted–hole bolts

Nowadays there are many types of glass fiber reinforced polymer(GFRP) composite beam and column joints, such as standard connection, bolted through connection, angle steel connection, tube connection and so on, most of which connected by high-strength bolts with round holes. In this paper, monotonic loading tests on GFRPcomposite beam and column joints connected by slotted-hole bolts were conducted. To compare the performance of different joints, two groups of specimens were used in this study; one of group was the beam-column joints connected by the angle steel, and other group was connected by the tube connection. Specimens with different bolt holes, side plate reinforcement condition, and different bolt pre-tightening forces were studied. Failure modes, bending moment curves, plastic rotation, and yield stiffness of the two groups of joints were compared. Results showed thatthe ultimate bending moment bearing capacity of specimens with side plates could be increased by 30%. Under the same conditions, the bearing capacity of the tube joints was about 10% larger than that of the angle steel joints. Although the bearing capacity of joints was not increased by using slotted holes, plastic rotation capacity and yield stiffness of joints with slotted-hole bolts were 1.1 times than that of the ordinary round-hole bolts joints.