Experimental evaluation of geometric factors affecting damage mechanisms in carbon/epoxy plates

Experimental parametric studies have been carried out to investigate the effects of four geometric factors on the mechanical behaviour of thin carbon/epoxy circular plates under quasi-static transverse loading. The geometric factors examined were two sizes and two nose shapes of indenters, two plate diameters and two boundary conditions. Generally, the effects have been found to be significantly coupled with one another so that none of the geometric factors could be ignored in an examination of mechanical behaviour. In particular, the nose shape of an indenter and the plate diameter were shown to have a greater influence on plate behaviour than the other two. Four major failure modes were found to operate in these loaded plates. While certain combinations of geometric factors promoted one type of failure mode, other combinations of the same factors favoured other types. Moreover, these failure modes were related to basic damage mechanisms only in a complex and collective manner.