Interface fracture mechanics: theory and experiment

The purpose of this paper is to review a methodology for predicting interface crack propagation. The materials will be taken to be isotropic and anisotropic. The first term of the asymptotic expansion for the stress and displacement fields is considered. A deterministic failure criterion derived from the interface energy release rate is described. In order to predict failure by means of a statistical approach, two statistical measures are examined. One makes use of a t-distribution for statistical intervals and the other uses the standard variate to determine a failure probability and confidence interval. The failure probability was set to 10%, that is there is a 10% probability that the next observation would unexpectedly be below the failure curve or surface in the safe region. For the t-statistic, there was a 50% confidence; for the standard variant model, there was a 95% confidence. Test results are presented with the failure criteria obtained and examined.