Strength of Slender Beams

Slender beams loaded in the usual manner t end to fail laterally at stresses often far below the yield point of the material. This fact is provided, for in design specifications by reducing the basic allowable stress in the extreme compression fiber for beams in which the ratio of length to width is greater than a prescribed maximum. The specified reduction is based more or less on semi-empirical considerations rather than on strict analytical study. In this paper the ultimate strength of slender beams is determined by rational methods similar to those generally accepted in column design, due consideration being given to highly probable imperfections in loading and beam shape.