Abstract：In order to supplement calculation method for overall stability of steel beams with restrains under uniformly distributed load in current codes for design of steel structures(GB50017-2003),theoretical formulations for overall stability of such beams were proposed by Rayleigh-Ritz method based on energy theory.Compared with corresponding formulas in AISC and BS5950 about overall stability of steel beam under random moment diagram,there exists large error in case that the proportion of the contribution to beam’s moment from the uniformly distributed load is large enough or that the steel beam is monosymmetric.Because influence from load location and monosymmetry of section on critical moment was not taken into account in AISC or BS5950,the method presented in the two codes were not applicable for such beams.Formulas presented by this paper for calculating the critical moment of steel beams with restrains under uniformly distributed load were well agreed with the results from FEM and fit for checking the overall stability of such beams.Therefore,research achievement by this paper can provide theoretical basis for current code for design of steel structures.
2012, Vol. 34 
