Strength Variation of Laterally Unsupported Beams

摘要: Nominally identical 25 rolled beams for each group of three different lengths are tested carefully under a concentrated load applied vertically at the midspan compressive flange span center. The variation geometrical and material imperfections measured influences various parameters on scattered test points lateral buckling reviewed. main parameter which highly ultimate strength is variable value actual plastic moment. obtained results also compared with existing data design formulas. coefficients increase beam length these values considerably low as past data. Finally, formula proposed to ensure empirically lower bound values.