Approximate Method of Elastic Buckling Strength Analysis for Irregular Frames

An approximate method is proposed to evaluate the elastic bucking strength of a multi-story multi-bay rectangular frame with irregular arrangements of beam and column stiffnesses and column axial force distribution, combining two methods separately developed by Sakamoto and Wood for single -story multi-bay frames and multi-story single-bay frames, respectively. Sample calculations were made including a 14-story 8-bay frame designed in the real practice, and 6-story 2-bay frames in which one column was extremely slender or subjected to excessive axial force. It is shown that the proposed method gives very good estimates to the buckling strength although the estimates are conservative or unconservative, with no clear tendency