At present, the compressive strength of composite laminates containing an o
pen-hole can be predicted theoretically by using fracture mechanics based m
odels such as the linear softening cohesive zone model. In this approach, t
he inelastic deformation associated with fibre microbuckling that develops
near the hole edge is replaced with an equivalent crack loaded on its faces
by a bridging traction which is linearly reduced with the crack closing di
splacement. By making use of this model, and by establishing an equivalent
hole diameter from X-radiographs and/or ultrasonic C-scan images, the resid
ual compressive strength after impact can be predicted. This paper outlines
how the 'equivalent hole' is determined and gives tabulated results of exp
erimental and theoretical data. It is also shown that these data are in goo
d agreement with each other for plain compression, open-hole compression an
d compression after impact strengths. (C) 2001 Elsevier Science Ltd. All ri
ghts reserved.