Study of the Mechanical Properties of Beam-Column Joints in a New Type of Aluminum Alloy Portal Frame

Abstract

In the article, the semi-permanent aluminum alloy portal frame is used as the research background, beam-column joints are used as the research object, and experimental and numerical analyses are carried out. The influence of different bolt diameters and arch angles on the mechanical properties of beam-column joints under vertical load was analyzed using five sets of experiments. The experimental results show that the load–displacement curves of different bolt diameters in the elastic stage are basically consistent. After entering the plastic stage, the ultimate load first increases and then decreases, and the ultimate displacement is basically consistent. According to the experiment, there is no significant difference in the load–displacement curve when the arch angle increases from 90 degrees to 108 degrees. When the arch angle increases to 126 degrees, the stiffness and ultimate bearing capacity of the node under vertical load significantly increase. Then, a numerical analysis model was established to analyze the mechanical performance of beam-column joints under horizontal loads. The numerical analysis results indicate that under horizontal load, as the diameter of the bolt increases, the yield load, yield displacement, ultimate load, and ultimate displacement of the beam-column node exhibit no significant changes, and the change amplitude is minimal. When the beam-column node is subjected to horizontal loads, as the arch angle increases, the yield and ultimate displacement increase by 2.14 times and 2.78 times, respectively, and the yield and ultimate load decrease by 58% and 48%, respectively. Finally, a simplified design method for beam-column joints was proposed based on experiments and numerical analysis.

Experimental Study on the Mechanical Properties and Health Monitoring Methods of Joints in AAPF

“…An AAPF mainly consists of joints between beam and beam, joints between beam and column, and aluminum alloy members [22]. Detailed numerical and experimental explorations were undertaken on aluminum alloy beam column joints earlier.…”

“…On the lower and upper I-beam flanges, 4 and 6 bolt holes were set up, while on the web, 6 bolt holes were set up. Meanwhile, bolt holes were also set up at the matching locations of the C-shaped connector web and flange [22]. The bolt hole diameter was calculated by adding 0.20 mm to the bolt diameter.…”

“…The length unit in the figure is mm. The H-shaped beams were sectioned and drilled in the factory, while the dual C-shaped connectors were welded from steel plates [22]. Afterwards, as displayed in Figure 2b, the two were delivered to the laboratory for connection and assembly.…”

“…In this article, we conduct test research and numerical simulation on the beam-beam joints of AAPFs. We analyze the force mechanism and deformation characteristics on beam-beam joints under vertical loads through experimental research of the bolt diameter and arch angle [22]. Then, the numerical models are established to further study the effect of arch angle on the stress characteristics of the beam-beam joints of AAPFs under horizontal loads [22].…”

“…We analyze the force mechanism and deformation characteristics on beam-beam joints under vertical loads through experimental research of the bolt diameter and arch angle [22]. Then, the numerical models are established to further study the effect of arch angle on the stress characteristics of the beam-beam joints of AAPFs under horizontal loads [22]. Finally, a health monitoring method for AAPF beam-beam joints based on displacement monitoring and frequency monitoring is invented.…”