Stability of Columns with Transient Loads

The dynamic deflection columns with general end fixity loaded with a transient variable compressive force is formulated by an integro-differential equation, which is reduced to a set of ordinary differential equations. For the special case of a hinged column, a stability criterion is obtained in explicit form via Liapunov's direct method. The stability criterion constitutes a relation between a bound on the amplification of an initial perturbation and the corresponding force pulse. The stability criterion is shown for three sample loadings: a trigonometric pulse; a parabolic pulse, and a set pulse. The amplification bounds are evaluated through comparison with the trajectory of maximum response of the governing differential equations of motion.