Buckling analysis of columns ended by rotation-stiffness spring hinges

Stabilities of compressed columns ended by spring hinges with particular rotation stiffness was a basic theory for more complex structures' researches and engineering, however investigations on calculation approaches for these columns were rarely reported. This paper focus on buckling analysis on these spring hinge ended columns, and the derivation of the columns' effective length factor equation were presented. Meanwhile a practical design formula to predicate the effective length factors was proposed and further validated to be highly accurate. Furthermore impacts of ideal-ends column method, which ignoring real ends' rotation stiffness, were investigated. Finally conditions making ideal-ends column method accurate enough in practice were put forward and the practical condition equations were proposed.