Simulation Techniques for Thin-Walled Circular Tubes

Finite element analysis (FEA) is widely used to investigate the crushing performance of thin-walled tubes, and carry out parametric studies. However, simulation results are not always in good agreements with experimental results especially in terms of deformation modes in published literature. In this paper, a systematic FEA study will be conducted to evaluate two main simulation techniques using indentation triggers and buckling modes to introduce imperfections in FEA. Axial compressive tests were first carried out on three types of thin-walled circular tubes with different geometrical parameters. The finite element models were subsequently developed and used to explore the effects of indentation triggers and buckling modes on the deformation modes and force-displacement curves of thin-walled tubes. The influences of indentation depths and indentation positions on the crushing performance were investigated. Similarly, the effects of the order of buckling modes and scale factors on the crushing characteristics were examined as well. It has been found that for thin-walled circular tubes, a suitable simulation technique with indentation triggers or buckling modes can be employed to precisely mimic the deformation mode and corresponding force-displacement curve. This study is expected to provide some practical techniques and insights into the numerical simulation of circular tubes.