Research On Mechanical Properties Of Double Cold Bending Thin-wall C Steel Beam Column Node

In recent years cold bending thin-wall steel get widespread concern in engineering forthe superior performance. At present it is more and more widely used in constructionindustry. This paper researched on mechanical performance of cold-formed steel beam-column node. Research method is that using general large-scale finite element softwareANSYS to simulate node. Node structure is as follows: beams and columns are connectedof cold-formed thin-walled C steel back to back; hot rolled steel plate is interpolated todouble limb in some distance; hot rolled steel plate and double limb C steel connected withboltes; in node area hot rolled steel plate and beam and column connected with eight bolts.Considing contaction this paper set up a double limb cold-formed thin-walled C steelnode, and compared with the experiment result. The results show that the finite elementmodel is correct. Then set other models using this model’s set parameters. Considering Csteel thickness, section size, hot rolled steel plate thickness and bolt spacing this paper setup72models. Through the monotonic loading, this paper analyzes the failure mode ofnode, the changes in the stress, the initial stiffness and ultimate bending moment. Theresearch coming to the conclusion: there are two kinds of failure modes, one is platedamage nearing the bolt hole, the other is C steel beams bending failure; ultimate bendingmoment increase when bolt spacing, hot rolled steel plate thickness or C steel thincknessincreased, and the effect of C steel thickness is largest; the initial stiffness increase whenbolt spacing, hot rolled steel plate thickness or C steel thinckness increased, and all thisthree have a significant impact on initial stiffness. At last this paper gives node advice asfollows: based on C steel sections in this paper, node plate thickness should take from8mm to10mm, bolt spacing should take from200mm to220mm.Based on analysis of double limb cold-formed thin-walled C steel node this paperestablished two kinds of bending moment-corner model, the power function model andlinear model. The power function model is accurate, but the form is complex; the form of linear model is relatively simple, but the accuracy needs to be improved.Some nodes were choosed for cyclic loading to analyze the hysteretic performance.The research coming to the conclusion: this kind of node’s ductility is general but energydissipation capacity is good; node stiffness degradation is serious with the increase of loadlevel; node haunched has influence on energy dissipation capacity but the effect is notobvious in bearing capacity.