Dynamic stability of an elastically restrained column subjected to triangulary distributed subtangential forces

The dynamic stability of a column subjected to triangularly distributed subtangential forces is investigated. The column is clamped at one end, and is supported rigidly at an arbitrary location. The column studied becomes unstable in the form of either flutter or divergence, depending on the degree of nonconservativeness of distributed subtangential forces and the location of support. The stability maps, which are produced from eigenvalue analyses, present two different types of instability domains. Through the numerical simulation, the following results are obtained: (i) When the nonconservativeness parameter, α, is less than 0.5, divergence appears only regardless of the existence of the rigid support. (ii) For α>0.5, the instability type changes with the position of a rigid support. (iii) When a rigid support exists, the transition position from flutter to divergence increases as nonconservativeness parameter increases. However, the transition position from divergence to flutter is decreased with increasing nonconservativeness. (iv) Boundary conditions of columns affect greatly both the instability type and the critical distributed subtangential force.