In this study, the experiments of 800 MPa high strength steel (HSS) welded I-section columns under axial compression are performed to investigate their local buckling behavior. The effects of width-to-thickness ratio and slenderness on the local buckling load are considered. Four different buckling modes of columns (i.e., web buckling, flange buckling, web and flange buckling, and global buckling) are designed. The local buckling load obtained from load-displacement curves and load-strain curves are investigated. New embedding coefficients of the web and flange in 800 MPa HSS welded I-sections are recommended. Design provisions in current specifications for predicting the ultimate bearing capacity of 800 MPa HSS welded I-section columns under axial compression are evaluated, and it is concluded that GB50017-2017, AISC360-16, and EN 1993-1-5 is a little overestimated for estimating the ultimate bearing capacity of 800 MPa HSS welded I-section columns under axial compression. A three-dimension finite element model is developed for predicting the ultimate bearing capacity of 800 MPa HSS welded I-section columns under axial compression, which is validated by test data. The effect of residual stress on the ultimate bearing capacity of 800 MPa high strength steel welded I-section columns is not obvious. A more accurate model for estimating the ultimate bearing capacity of 800 MPa HSS welded I-section columns under axial compression is recommended.

在这项研究中，进行了800 MPa高强度钢（HSS）焊接的I型截面柱在轴向压缩下的试验，以研究其局部屈曲行为。考虑了宽厚比和细长度对局部屈曲载荷的影响。设计了四种不同的柱屈曲模式（即腹板屈曲，翼缘屈曲，腹板屈曲和翼缘屈曲以及整体屈曲）。研究了从荷载-位移曲线和荷载-应变曲线获得的局部屈曲载荷。建议在800 MPa HSS焊接I型截面中，腹板和法兰的新嵌入系数。评估了当前规范中用于预测800 MPa HSS焊接I型截面柱在轴向压缩下的极限承载力的设计规定，并得出以下结论：GB50017-2017，AISC360-16，和EN 1993-1-5有点高估了估计800 MPa HSS焊接I型截面柱在轴向压缩下的极限承载力。建立了三维有限元模型，用于预测在轴向压缩条件下800 MPa HSS焊接工字型钢柱的极限承载力，并通过试验数据进行了验证。残余应力对800 MPa高强度钢焊接I型截面柱的极限承载力的影响并不明显。建议使用更准确的模型来估算800 MPa HSS焊接I型截面柱在轴向压缩下的极限承载力。建立了三维有限元模型，用于预测800 MPa HSS焊接工字型钢柱在轴向压缩下的极限承载力，并通过试验数据进行了验证。残余应力对800 MPa高强度钢焊接I型截面柱的极限承载力的影响并不明显。建议使用更准确的模型来估算800 MPa HSS焊接I型截面柱在轴向压缩下的极限承载力。建立了三维有限元模型，用于预测在轴向压缩条件下800 MPa HSS焊接工字型钢柱的极限承载力，并通过试验数据进行了验证。残余应力对800 MPa高强度钢焊接I型截面柱的极限承载力的影响并不明显。建议使用更准确的模型来估算在轴向压缩下800 MPa高速钢焊接的I型截面柱的极限承载力。