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 natural 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 relation to prestress rate. Discontinuities of the critical force have been observed for the border value of the prestress leading to the instability of the column without the external load. Although each prestress lowers the critical force, it can be used for passive vibration control.