A progressive damage model is presented for the prediction of the overall n
on-linear tensile behaviour of knitted fabric composites. The model is an e
xtension of a recently developed inclusion method for textile composites, t
aking into account the major damage modes of knitted fabric composites simu
ltaneously. Matrix non-linearities, playing an important role in the behavi
our of knitted fabric composites, are implemented using the secant stiffnes
s method. Whereas, non-linearities can be attributed to different sources,
depending upon the resin toughness, only some limited yielding was currentl
y investigated. Yam/matrix debonding, predominantly responsible for the kne
e behaviour of knitted fabric composites, is investigated using a simple in
terfacial failure criterion. A selective degradation scheme based upon a fi
nite set of interfacial damage state variables is employed in the reduction
of the inclusion stiffness. Finally, a Hoffman criterion is used for yam f
ailure. The model was used to simulate the tensile behaviour of knitted fab
ric E-glass/epoxy composites, showing the ability to predict the material r
esponse with reasonable accuracy in the region before ultimate failure. (C)
2001 Published by Elsevier Science Ltd.