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

Monotonic loading tests on GFRP composite 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. The test loading device was a single channel electro-hydraulic servo loading system. The level of actuator deformation range was 200 mm, which could exert the maximum load of 250 kN. To facilitate loading, the GFRP column was fixed under the loading device. By applying a vertical displacement actuator in the beam end and connected actuator by a steel tube at GFRP beam loading point, it was to ensure the stability of loading position and keeping verticality of actuators. The rotation angles and bending moment of the joint were calculated according to the related equations. So the relation of moment-rotation of joints could be obtained to analyze mechanical performance for GFRP composite beam and column joints connected by slotted-hole bolts.