Fracture control: Past,present and future

The treatment of this topic is selective; it concentrates initially on the recognition of fracture problems and the experimental investigations that developed in response to them, including fracture-propagation studies in plates and pipelines. Attention is then given to several criteria for crack extension that have been investigated, and to the methods used. Although an understanding of stationary crack stress fields has been established, it is concluded that the position with just-moving cracks is less satisfactory, so that further progress is impeded for lack of a sufficient basis of comparison. Many of the practical problems most in need of fracture-analysis techniques involve complex shapes, and it is suggested that theoretical stress analysis even using numerical methods is unlikely to provide complete solutions in the near future. In helping to resolve the remaining uncertainties with fracture criteria, and in handling complex shapes of component there should be more scope for experimental methods in fracture mechanics than ever before.