Investigation of crashworthiness behavior of thin-walled cylindrical tubes with cutting-edges under axial and oblique quasi-static loading

The energy absorbers are the mechanical structures that are used for transformation some or whole kinetic energy resulted from collision to other kinds of energy. Efficiency improvement of these absorbers has been always the goal of researchers, and so the various methods have been used to this field. In this paper, firstly, the effect of cutting-edges on initial crushing load, mean crushing load, absorbed energy and the mode of crashworthiness of thin-walled cylindrical aluminum tubes is investigated. Then the effects of geometrical dimensions of the tube-like thickness, diameter, semi-apical angle, the geometry and dimensions of the edge and the angle of applied load on the crashworthiness behavior of thin-walled structure are examined. The results show that creation of symmetrical cuttings on the edge, decrease the initial crushing load. These cuttings decrease mean crushing load and absorbed energy too. These declines in mean crushing load and absorbed energy are negligible in compared to initial crushing load. This phenomenon makes this system useful for cases in which initial shock is significant. The results also show that initial crushing load for the 2 squares cutting-edges and for the 4 cutting-edges were reduced about 18.7 % and 34 %, respectively, compared to the initial crushing load of the thin-walled cylindrical tube-like without cutting-edges.