Buckling Properties of Monosymmetric I-Beams

Approximations are derived for the section properties required for the calculation of the elastic critical loads of monosymmetric I-beams and are found to be related to the ratio of compression flange and section minor axis second moments of area. Approximations are obtained that are applicable to I-sections with unequal and lipped flanges and that are in close agreement with accurate calculations of the monosymmetry section properties made for a wide range of cross sections. An improved design rule is proposed for the elastic critical stress of a monosymmetric I-beam. A comparison is made of the results obtained using the proposed rule and the present rules of the AS 1250, BS 449, and AISC Specification.