Numerical analysis of cold-formed steel non-symmetric lipped angles under centered compression
Keywords:
cold-formed steel, unequal lipped anglesAbstract
The present work brings a numerical, non-linear physical and geometric analysis using the Finite Element Method, of asymmetrical stiff angles, using the Ansys software. The simulations employed two magnitudes of initial imperfections, and aimed to find the critical buckling loads and failure modes, observing local, global instabilities and the interaction between both. The results obtained were compared with experimental tests, performed by Young and Chen (2008), and with the values proposed by the brazilian standard ABNT NBR 14762: 2010, using the Direct Resistance Method. The procedure adopted for the simulations proved to be quite efficient, producing very interesting results compared to the experimental ones, showing the reliability of this method for the analysis of cold-formed steel asymmetrical angles. The initial imperfections adopted demonstrated that, for the same profile, it was not the same magnitude that produced the best results, emphasizing the importance of your choice. The calculation procedure of ABNT NBR 14762: 2010, using the Direct Resistance Method, proved to be coherent for bars up to 1000 mm, but very conservative for those of greater length, with the increase of slenderness.
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References
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