Evaluation of Gusset Plate Buckling Strength Using Stability Functions

A method is proposed to calculate the buckling strength of gusset plates (GPs) using stability functions. The method requires a division of GPs into sub-elements and calculation of their equivalent bending stiffness. Using these sub-elements, a GP stiffness matrix can be formulated. The elastic buckling load is the axial load that makes the determinant of this matrix equal to zero. The method is evaluated by comparing its strength predictions against the buckling load of tested GPs reported in literature and the predictions obtained using the AISC method. When the brace end of the GP was fully free or had rotational restraints, the method predicted an average of 18% and 92% respectively of the experimental values. The AISC method provided 13% and 35% of the experimental values when using effective length factors of 1.2 and 2.0 respectively.