Stability of Large-Size and High-Strength Steel Angle Sections Aff ected by Support Constraint

The infl uence of support stiff ness on the eff ective calculated length which plays an essential role in the axial compression stability of steel memeber is always ignored due to the ideal support constraint that is diffi cult to achieve in the test. In this paper, the calculation method of the eff ective length factor was put forward by the mechanical model of the axially compressed member. The supports rotation stiff ness of large-size and high-strength steel angle sections (LHS) under the test condition were measured, and the eff ective length of each specimen was modifi ed. And 36 LHS members were tested under axial load. Then the stability responses for LHS members were studied using fi nite element analysis considering more section profi les and the wide range slenderness ratios. Moreover, the buckling strengths were compared with the current design codes. The results show that the support constraint has a signifi cant infl uence on the bearing capacity of the LHS member. Considering the infl uence of support restraint, when the slenderness ratio is small, the stability factor is higher than the column curve in current codes; when the slenderness ratio is large, b-curves in both GB50017-2017 and Eurocode 3 are conservative, whereas other codes are marginally unsafe. Finally, a new column curve was proposed to predict LHS members’ capacity more accurately. KCI Citation Count: 0