EVALUATION OF COUPLED LOCAL BUCKLING STRENGTH OF SQUARE HOLLOW SECTION MEMBER UNDER BIAXIAL BENDING SHEAR FORCE AND AXIAL FORCE

Abstract

The purpose of this study is to present approximate formulas for elastic local buckling strength of square hollow section members under biaxial bending shear force and axial force. For this purpose, buckling analysis considering coupled effects of plate elements and complex stress conditions by bending, shear, and compression is conducted using energy method. Effects of determinants of the buckling strength, boundary conditions, aspect ratio, and stress conditions of the plate elements are understood. Simple approximate formulas for the coupled local buckling strength corresponding to boundary conditions at both ends, shape and stress distribution with respect to the members are presented.