LATERAL-BUCKLING TESTS OF COLD-FORMED RHS BEAMS

In this paper, tests on the lateral buckling of cold-formed rectangula r hollow sections (RHS) beams under uniform bending moment are describ ed. The section size chosen for testing is 75 x 25 x 2.5 mm, which is the largest depth/width ratio manufactured in Australia. The beam span s varied from 2,000 to 7,000 mm to produce a large range of beam-slend erness ratios. Carefully designed loading and support systems were use d in the tests to apply gravity load through the centroid of the secti on and to ensure that simply supported end conditions were achieved. T he test results are compared with existing design models and standards . An improved design rule is given for the lateral buckling of cold-fo rmed RHS beams.