Finite Element Analysis of Ultimate Load Carrying Capacity of 800 MPa High-strength Steel T-shaped Section Axial Compression Members

Aiming at instability of 800 MPa high-strength steel T-section axial compression members, a finite element analysis model was established based on ABAQUS software, and the ultimate bearing capacity. The effect of residual stress, geometric initial defects, flange width-thickness ratio, web height-thickness ratio and member length-thinness ratio on the ultimate load carrying capacity of the member was analyzed by the finite element model, and the ultimate bearing capacity results of the T-section axial compression members made of high-strength steel were compared with those specified in the GB 50017—2017 design code series. The results show that: the finite element model can accurately simulate the buckling behavior of the test member; the peak residual stress has a small effect on the bearing capacity of the short column, while it has a large effect on the bearing capacity of the large slenderness member; the initial bending of the test piece and the buckling of the plate have a large effect on the ultimate bearing capacity of the small slenderness member; with the increase of the slenderness of the member, the ultimate load capacity of the member exhibits a decrease in sensitivity with changes in the flange width-to-thickness ratios, and the change of the high-thickness ratio of the web is similar to it. The calculation results are in good agreement with the b class column curve in GB 50017—2017 standard, and it is recommended to use the b class column curve to calculate the ultimate bearing capacity of the axial compression members of 800 MPa high strength steel welded T-shaped section.