Lateral surface contraction of an elastic cracked plate. Three dimensionaleffects.

We study here the out-of-plane displacement field near the crack tip of an elastic cracked plate. The crack is orthogonal to the free-border of the pl ate and subjected to a remote mode-I loading. Previous works [I] reveal act ually strong three-dimensional effects within a radial distance of about on e half thickness from the crack tip. A finite element approach and an exper imental study using a Michelson interferometer, lead us by identification, to formulate anew law representing the out-of-plane displacement in the who le region near the crack tip.