Natural Frequencies of Thin‐Walled Bars of Open Cross Section

The natural vibration frequencies of thin‐walled bars of open cross section are studied, with particular emphasis on the influence of asymmetry and destabilizing forces on the interaction between various modes. It is concluded that interactive vibrations are induced by both asymmetry and destabilizing forces. The validity of the solutions obtained is confirmed by the fact that the lowest natural frequencies reduce to zero when the applied forces are equal to the static critical forces for instability in the corresponding modes.