Hybrid metal-composite conical tubes for energy absorption; theoretical development and numerical simulation

In this paper, the crushing behavior of hybrid metal-composite conical tube under dynamic loading is studied. An efficient analytical solution for FML conical tubes consist of any number of metal and laminated composite layers is developed. In the analytical analysis, the mean collapse load of structures subjected to axial loading was predicted while its accuracy is validated via experimental tests and numerical simulation. Numerical simulation of the structure is also done using explicit dynamic finite element software in order to investigate the effects of different parameters on crushing characteristics of various structures. On the other hand, new values for failure energies of fiber reinforced composites are proposed in the failure evolution criteria in the finite element model. It leads to good agreement between FE simulations and experimental test other. Moreover, a comprehensive parametric study has been done in order to investigate the effect of various parameters including semi-apical angle, ply pattern of laminated composite, diameter of tube, wall thickness and material properties of tubes on energy absorption capacity and crashworthiness characteristics of various considered specimens. Finally, the crashworthiness capacity (SEA and CLE) with respect to semi-apical angle and ply pattern of laminated composite optimized in order to obtain a desired collapse mode. Based on the obtained results the optimized structure is determined. Also, crushing behaviors of various specimens predicted beyond the tested configurations using response surface methodology (RSM).