Characterization of asymmetrical beam instability to impulsive load

Asymmetrical instability of a 3-DoF Shanley-type beam model subjected to impulsive transverse load is investigated. The effects of viscous damping on the asymmetrical response of the model are discussed. A new energy analysis approach is proposed for identification of the response category when the beam model is subjected to different impulsive loads. Through the energy analysis, three-dimensional Poincaré maps in terms of the displacement variables and the modal participation factors are plotted. Parametric studies for identifying the critical load above which asymmetrical instability occurs are carried out. Influences of the load duration, the material and geometrical parameters on the asymmetrical instability are demonstrated. The characteristic diagrams show clearly when the asymmetrical instability of the model occurs. The curves are also capable of predicting the final response mode if an external impulsive load is given to the beam model.