A possible method for assessing vehicle crashworthiness involves crashing the vehicle into a load cell wall faced with aluminium honeycomb. Optimisation of this approach requires an understanding of the force transmission characteristics of aluminium honeycomb structures. Quasi-static crush and dynamic impact experiments were used to investigate force transmission characteristics for three types of aluminium honeycomb. Key findings were that force level is affected by loading rate (up to a 40% increase at the maximum 15m/s test speed was measured) and by penetration tearing the of the aluminium honeycomb cell walls (tear forces of between 0.9kN to 4.0kN were recorded), whilst force distribution is affected by relative density and depth of the aluminium honeycomb (increased load spread). Other important findings were that a 1-2mm pre-crush reduces an initial peak in the force level whilst the addition of in-plane loading results in force redistribution (due to rotation/buckling of the aluminium honeycomb) and reduction in force level (due to fracture of the aluminium honeycomb). Another approach to assessing crashworthiness is to use numerical simulation (finite element modelling). Two approaches to finite element modelling of aluminium honeycomb were investigated. A continuous mesh approach was found to prevent the localised penetration observed in the experimental study, resulting in a significant increase in force level and distribution. A discrete mesh approach allowed localised penetration, but the mesh density was too coarse to be able to reliably predict the force levels and distributions found in the experimental study. Increasing the mesh density resulted in the HC model becoming unstable. Unlike a continuous mesh model, in which individual columns stabilise neighbouring columns, relative movement of columns is possible in the discrete mesh model. This places greater emphasis on individual column stability. Column stability was shown to be dependent on loading condition, slenderness ratio (column area relative to height) and honeycomb element stress/strain profile.

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