A systematic parametric study has been conducted to investigate the behaviour of lean duplex stainless steel semi-elliptical hollow section members subjected to torsion, using finite element software, Abaqus. The finite element models were initially validated with reliable experimental results; upon which parametric study was conducted. Effects of various key parameters such as aspect ratio, curve length, size and thickness of cross-section were studied. Based on the finite element study, sections of higher aspect ratio, curve length, larger size, and higher thickness were found to have more torque carrying capacity. Available design equations for plates under shear loading were checked for their applicability to the design of semi-elliptical hollow sections subjected to torsion. An attempt has also been made to develop design equations for lean duplex stainless steel semi-elliptical hollow section under torsion, based on EN 1993-1-4: 2006 + A1. Additionally, design equations based on deformation based method (in line with continuous strength method) were also proposed. The proposed equations were found to give reliable results for design of lean duplex stainless steel semi-elliptical hollow section members under torsion.

中文翻译：

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精益双相不锈钢半椭圆空心截面构件扭转行为的数值研究

已使用有限元软件Abaqus进行了系统的参数研究，以研究倾斜的双相不锈钢半椭圆形空心截面构件的性能。最初使用可靠的实验结果验证了有限元模型；对其进行了参数研究。研究了纵横比，曲线长度，横截面大小和厚度等各种关键参数的影响。在有限元研究的基础上，发现高纵横比，曲线长度，较大尺寸和较高厚度的截面具有更大的扭矩承载能力。检查了在剪力作用下板的可用设计方程，以了解其在受扭的半椭圆空心截面设计中的适用性。还根据EN 1993-1-4：2006 + A1尝试开发了扭转状态下的精益双相不锈钢半椭圆空心截面的设计方程。此外，还提出了基于变形方法（与连续强度方法一致）的设计方程。发现所提出的方程为扭转作用下的精益双相不锈钢半椭圆形空心截面构件的设计提供了可靠的结果。