The role of prestressing in establishing regions of instability for a compound column under conservative or non-conservative load

The influence of prestressing of a non-linear two-member column on its natu ral vibration and stability is studied. The perturbation method is used for solving the problem. Regions of divergence and flutter instabilities for a column has been determined on the basis of courses of eigencurves in relat ion to prestress rate. Discontinuities of the critical force have been obse rved for the border value of the prestress leading to the instability of th e column without the external load. Although each prestress lowers the crit ical force, it can be used for passive vibration control. (C) 2000 Academic Press.