1. Beijing Advanced Innovation Center for Future Urban Design, School of Civil and Transportation Engineering, Beijing University of Civil Engineering and Architecture, Beijing 100044, China;
2. Beijing Higher Institution Engineering Research Center of Structural Engineering and New Materials, Beijing University of Civil Engineering and Architecture, Beijing 100044, China;
3. Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
To exploring axial bearing capacity of circular hollow section steel K-joints strengthened by collar plates, the axial loading tests of two groups, totally four circular hollow section steel K-joints were conducted, the deformation and failure modes of the joints were studied. The effects of the brace to the chord diameter ratio β and collar plate reinforcement methods on the ultimate strength and load-displacement curves were analyzed. The research showed that the deformation and failure modes of the joints were characterized by plastic deformation of braces, local dents of chords, and brace fractures and weld cracking. The load increased rapidly at the initial stage of loading. As the actuator displacement increased, the load growth rate became slower and then the peak appeared, after that the load began to decrease. The increase of the β and the collar plate reinforcement had an obvious improvement on the ultimate strength of the K-joint, and the ultimate bearing capacity were respectively increased by at least 35% and 27%.
HOU C, HAN L H, MU T M. Behaviour of CFDST Chord to CHS Brace Composite K-Joints:Experiments[J]. Journal of Constructional Steel Research, 2017, 135:97-109.
FENG R, LIN J, MOU X. Experiments on Hybrid Tubular K-Joints with Circular Braces and Square Chord in Stainless Steel[J]. Engineering Structures, 2019, 190:52-65.
NASSIRAEI H, ZHU L, LOTFOLLAHI-YAGHIN M A, et al. Static Capacity of Tubular X-Joints Reinforced with Collar Plate Subjected to Brace Compression[J]. Thin-Walled Structures,2017,119:256-265.