Energy Absorbing Qualities Of Fiber Reinforced Plastic Tubes

One problem in incorporating composite materials in primary fuselage structures of helicopters, is fulfilling the crashworthiness requirements. This is due to the low strainto- failure characteristics of composite materials. Also, information about the crash impact behaviour of composites is rather limited. To obtain more information about the energy absorbing capability of composite structures, a very simple geometrical shape – the tube – was chosen for parametric studies. Also, the tube itself can be directly used as a load carrying structural member, i. e. in the landing gear, engine and transmission mounts, or seatstruts-structural parts where good energy absorption during a crash impact is an additional requirement. The investigation includes material variation (GFRP, CFRP, Kev/ep), influence of foam fillings different fiber orientations (±15°, ±30° ±45° ±60°, 90° ) and various failure trigger mechanisms. So far only the axial crushing has been examined. This has been done under quasi-static as well as impact loading. With one CFRP-tube configuration the influence of impact velocity was studied.