BENDING TEST ON COLD-FORMED STEEL BOX BEAMS WITH LARGE CROSS-SECTION
Keywords:
Bending test, cold-formed steel, box beam, buckling modeAbstract
This research studies a bending test of cold-formed steel box beams with large cross-sections. Torsional rigidity of an open single C-section is weak since a cold-formed steel cross-section usually consists of thin elements. With this lack of thickness, buckling in the compression elements is introduced including local, distortional, and lateral-torsional buckling. To improve torsional rigidity and extend further investigation, flexural tests on a built-up box beam assembled with 2 C-sections were conducted in this study. C30024 was selected as the large cross-section, and stiffening plates and self-drilling screws were used as fasteners on both the top and bottom flanges of each C-section. A 4-point bending test and simply supported condition were employed as specimens to achieve a series of bending tests under pure moment. In addition, the influence of the connection spacing on the flexural behavior was investigated at L/2, L/3, L/4, and L/6. The maximum loads and failure modes are examined and presented, and it was observed that there was no failure of the stiffening plates and self-drilling screws.
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