FINITE-ELEMENT ANALYSIS OF BEAM SPECIMENS USED TO MEASURE THE DELAMINATION RESISTANCE OF COMPOSITES

The energy release rates G applicable to various beam specimens used to measure the delamination resistance of composites have been calculated using finite element methods. The results have been compared with beam theory solutions, G(BT). While appreciable discrepancies exist, it has been found that the differences are expressible through a nondimensional parameter, rho, identified from orthotropy rescaling. Consequently, accurate solutions for G are presented in terms of G(BT), qualified by analytical series functions containing rho.