The objective of this study is to examine the relationship between battened built-up columns and frames about buckling. The buckling strengths, buckling modes and bending moment of one bay - n stories frame with rigid beams are calculated by the energy method. The results are compared with those of obtained by the Bleich's formula and correct solutions. Although the buckling strengths by Bleich agree fairly well with the correct values, it is shown that the strengths obtained by Bleich formula are neither the upper bound nor the lower bound. And buckling strengths calculated by the energy method estimate the correct strength within 5% error when the value of stories n is more than 2. Moreover, Bleich's moment distributions correspond to those of obtained by the energy method.

Keywords: Built-up compression member, Flexural buckling, Energy method, Buckling equation, Moment distribution, Bleich's formula.