Numerical Simulation of the Collapse of Stepped Circular Tube Subjected to Oblique Load
In this paper, the crushing behavior of stepped circular tubes under oblique compression is studied by finite element method (FEM) analysis. It is found that the stepped circular tubes exhibit good response to oblique load. The deformation of the tubes can be classified into stable and unstable modes depending on whether break point is observed in the compressive load curve. In the stable mode, the tube stays erect and absorbs compressive energy to the same extent as it absorbs axial load. However, in the unstable mode, the tube does not stay erect and can bear only much lower compressive load than that of axial crushing. The two deformation modes can be controlled by the geometry of the tube. The compressive load of the stepped tube under oblique crushing increases as the difference between the radius of the large tube and small tube decreases and as the total length of the tube increases. For geometries that take values near the boundary between the stable and unstable modes in the mode map, the stepped tubes exhibit maximum absorption efficiency. Moreover, the absorption efficiency of stepped tubes is proportional to thickness to about the 1.8 power.
Huixuan Zhang, Ye Han, Fuxiao Chen and Jiuba Wen
D. H. Chen and L. Yang, "Numerical Simulation of the Collapse of Stepped Circular Tube Subjected to Oblique Load", Applied Mechanics and Materials, Vols. 117-119, pp. 531-538, 2012