Dynamic plastic failure of a free–free slender tube under unsymmetrical linear distributed pressure

By employing theoretical analysis based on the rigid, perfectly plastic material idealization and finite element method based on elastic, perfectly plastic material idealization, a comprehensive analysis of dynamic behavior of a free–free tube beam under arbitrary unsymmetrical linear distributed pressure has been made in this paper. Because the distribution of the load is more general, the theoretical result can be degenerated into some special cases which had been discussed in [1] and [2]. The comparisons between results of present theoretical analysis and those obtained from finite element calculation show that there is a dangerous region between the center of the tube beam and the pressure peak position, in which the local plastic collapse may take place. The theoretical results can provide a simple approximate estimation of local plastic failure position and deformation profile of aerospace vehicles subjected to the pressure pulse resulting from an explosion.

► Theoretical analysis and FEA are used to study the response of a free-free tube beam.
► The pressure distribution is more general and could be degenerated into some special cases.
► The plastic hinge approaches to pressure peak point with increasing intensity.
► There is a high curvature region for the tube beam.
► The segment between center of beam and pressure peak point is most liable to breakup.