Buckling of Columns With Internal Slide Release: A Recent Erroneous Conclusion and Lessons From It

A recent paper derived equations which showed that the clamped–clamped and clamped–pinned buckling loads of columns with a transverse slider were invariant, with the values π²EI/L² and π²EI/4L², respectively, regardless of the position of the slider. It is shown that these results are both wrong, partly due to transverse force being confused with shear force. It is also shown that the basic equation used to obtain these erroneous results has a much simpler form than the one in the recent paper and that when used properly is a powerful tool for understanding and solving rapidly a range of buckling problems. These include cantilever and symmetric pinned–pinned stepped columns and symmetrical and symmetrically loaded, rigidly jointed, unbraced, single bay, multi-storey, plane frames.