Stainless steel has superior corrosion resistance, fire resistance, and maintenance compared to carbon steel as a structural material. Although austenitic stainless steel (STS304) has mainly been used as structural steel material, lean duplex stainless steel, STS329FLD with lower nickel component (reduced to 0.5–1.0% in KS) has recently been developed as a substitute for austenitic stainless steel. Since duplex stainless steel is less costly and has excellent corrosion resistance compared with austenitic stainless steel, its use is expected to increase in the field of industry and infrastructure. However, there have been little data to apply this duplex stainless steel member to structural use. This paper presents an experimental and numerical investigation on the structural behaviors of austenitic stainless steel (STS304 TKC) and lean duplex stainless steel (STS329FLD TKC) circular columns subjected to concentrically axial compression. Test specimens were fabricated with four types of column lengths and slender ratios and were tested with both fixed ends. Duplex stainless steel (STS329FLD TKC) material showed higher yield stress and tensile strength than those of austenitic stainless steel (STS304 TKC). The results such as buckling shapes (local and global buckling) and ultimate strengths through additional parametric analysis were investigated and were compared with those predicted by current design codes [American Society of Civil Engineers (ASCE) and Eurocode (EC 3)] and by design equations of previous studies. Modified buckling equations were recommended considering the initial imperfection factor and limiting slenderness of two types of stainless steel circular columns and the accuracy of buckling strength prediction was improved.

与作为结构材料的碳钢相比，不锈钢具有优异的耐腐蚀性，耐火性和维护性。尽管奥氏体不锈钢（STS304）主要用作结构钢材料，但最近已开发出镍含量较低的贫双相不锈钢STS329FLD（在堪萨斯州降低至0.5-1.0％）来替代奥氏体不锈钢。与奥氏体不锈钢相比，由于双相不锈钢价格便宜，并且具有出色的耐腐蚀性，因此在工业和基础设施领域，其使用量有望增加。然而，几乎没有数据将该双相不锈钢构件应用于结构用途。本文对奥氏体不锈钢（STS304 TKC）和贫双相不锈钢（STS329FLD TKC）圆柱在同心轴向压缩下的结构行为进行了实验和数值研究。用四种类型的色谱柱长度和细长比制备测试样品，并用两个固定端进行测试。双相不锈钢（STS329FLD TKC）材料显示出比奥氏体不锈钢（STS304 TKC）高的屈服应力和拉伸强度。研究了诸如弯曲形状（局部和整体弯曲）和通过附加参数分析得出的极限强度等结果，并将其与当前设计规范[美国土木工程师学会（ASCE）和欧洲规范（EC 3）]以及设计所预测的结果进行了比较先前研究的方程式。