Flexural Buckling of Simply Supported Columns with 'Rigid End Links' - the Key to Interpret Pin-Ended Angle Column Test Results?

摘要

The paper begins by deriving and validating an analytical expression providing flexural buckling loads of uniformly compressed simply supported columns formed by a flexible central segment and two "rigid end links". It proves that the end links lower the buckling load by an amount varying with the link length, at a rate that is very high for small lengths. Then, this finding is used to re-interpret available test results on simply supported angle columns with intermediate lengths (i.e., exhibiting critical flexural-torsional buckling), by showing that the rigid links used in these tests provide a mechanically sound explanation for their (apparently paradoxical) observed failure modes, involving exclusively minor-axis flexure. Li order to further assess the impact of the rigid end links on the intermediate angle column structural response, the paper closes with a numerical investigation concerning the comparison between the elastic post-buckling behaviors (non-linear equilibrium paths) of columns with rigid end links exhibiting various lengths.