Finite element simulation of woven fabric composites

Two dimensional generalised plane strain finite element models have been developed to simulate some of the different local fabric geometries which influence the damage development seen in woven fabric laminates as a function of number of reinforcing layers. It is shown that the stiffness is relatively insensitive to such geometric variations, but that the strain energy release rate associated with crack formation is influenced significantly by the crack location. In particular, where the formation of a crack is associated with local bending deformation, the energy release rate increases with the degree of bending; for configurations leading to a high degree of bending, a geometrically non-linear analysis is required to determine the energy release rate accurately. For several of the crack geometries studied, the values of the energy release rates for crack formation are significantly larger than the values for central 90degrees ply cracking and surface 90degrees ply cracking in equivalent (0/90)s and (90/0)s cross-ply laminates. The implications of the various effects for simulation of crack development in woven cross-ply laminates are discussed. (C) 2004 Published by Elsevier Ltd.