Buckling of a Rectangular Frame Revisited

An investigation of the buckling under uniform beam load of a rectangular frame with columns restrained by linear rotational springs indicates that for certain ranges of bending stiffness ratio, length-height ratio, and support rotational stiffness parameter, the antisymmetrical bifurcation mode of buckling does not exist and buckling occurs at a symmetrical deformation limit load. The ranges of parameters for which this phenomenon may be important are studied.