Abstract:
Aiming at instability of 800 MPa high-strength steel T-shaped section axial compression members, a finite element analysis model was established based on ABAQUS software to analyze the effect of residual stress, geometric initial defects, flange width-thickness ratio, web height-thickness ratio and member length-thinness ratio on the ultimate bearing capacity of the member. A relationship curve between regularized aspect ratio and overall stability coefficient was established, and the simulation results of the ultimate bearing capacity of T-shaped section axial compression members of high-strength steel were compared and analyzed with the GB 50017—2017 series design specifications. The results show that the established finite element model can accurately simulate the buckling behavior of test members,and the peak residual stress has a small effect on the bearing capacity of short column, while it has a significant effect on the bearing capacity of large slenderness members. The initial bending of the test piece and the buckling of the plate have a significant effect on the ultimate bearing capacity of small slenderness members. With the increase of the member slenderness, the sensitivity of the ultimate bearing capacity of the member decreases with variation of the flange width-to-thickness ratios, and the variation law of the high-thickness ratio of the web is similar to it. The calculated stability coefficient is 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 axial compression members of 800 MPa high strength steel welded T-shaped section.