Experimental Investigation on Flexural Behavior of Cold-formed Steel Semi-oval Hollow Sections

Abstract

The semi-oval hollow sections have recently emerged in steel manufacturing industry and offer an exciting alternative for engineers and architects owing to their complementary qualities of aesthetic appearance and sound structural efficiency. An experimental investigation was performed on cold-formed steel semi-oval hollow sections subjected to bending about major axis in both positive and negative directions. A total of 20 bending tests, including 10 four-point bending tests and 10 three-point bending tests, was conducted in order to investigate the flexural behavior of such sections under constant moment and a moment gradient, respectively. The moment-curvature and momentrotation relationships are presented for each beam specimen under constant moment and a moment gradient. It should be noted that the current design rules for cold-formed steel structures, such as North American, Australian/New Zealand and European specifications, do not cover the design of semi-oval hollow sections. Hence, the test strengths were only compared with the design strengths predicted by the Direct Strength Method for cold-formed steel semi-oval hollow section flexural members.