Compression failure of laminated composite cylindrical shells under axial loading

摘要

This paper addresses failure characterisation and prediction for moderately thin-walled carbon fibre/epoxy cylinders subjected to compressive axial loads. Specimens of [0_2/90_2]_s configuration failed in a local buckling mode, with virtually no prebuckling acoustic activity. In the case of the [90/45/-45/0]as laminates there was moderate acoustic activity at load levels as low as 40 percent of the final failure load, suggesting that damage was occurring within the laminate well before the final failure in a buckling related mode. The [45/-45/45/-45]s specimens demonstrated significant acoustic activity from low load levels and failed by meterial fracture. A finite element analysis based design methodology is presented which considers failure modes such as local buckling, intralamina and interalmina damage. A key feature of the new methodology is that it recognises the significant effect that geometric imperfections have on the localised laminate stress fields, as well as on local buckling behaviour.