Abstract
This Special Issue of Engineering Fracture Mechanics is a collection of papers from the Workshop on “Integrity of Light-Weight Thin-Walled Structures” held at the GKSS Research Center Geesthacht, Germany on October 24–25, 2006 jointly organised by the GKSS, the Alcoa Technical Centre (PA) and the Cooperate Research Centre of EADS Germany.
Demands for weight and cost reduction have promoted the use of thin-walled structures in many industrial applications such as pipelines, ship hulls, bridges, industrial buildings and many others, but most prominently in aerospace. The continuing development is characterised by the introduction of new light-weight alloys as well as innovative design principles and joining technologies. To avoid catastrophic failure, effective flaw assessment methods have to be provided which take into account characteristic features of thin-walled structures, such as pronounced stable crack extension prior to fracture, the effect of stiffening elements and other items.
The workshop aimed at bringing together practitioners in the field and scientists engaged in the development of novel methods. As a result the papers – although dealing with the same issue: the assessment of thin-walled structures – address a wide range of approaches reaching from conventional stress intensity factor based R curve analyses up to recent developments in sub-structured finite element methods.
A review of existing conventional, as well as rather novel methods, is provided in an introduction paper by the editors, which discusses the methods with respect to specific requirements such as the ability to predict crack extension in stiffened and un-stiffened riveted, welded and bonded structures. The various aspects and approaches are further discussed in technical papers. Three papers, Pirondi and Fersini, James et al. and Heerens et al. focus on the crack tip opening angle (CTOA) concept, which they discuss from different points of view. The application of a cohesive zone model to a stiffened integral structure, including the prediction of crack branching is demonstrated by Scheider and Brocks. Two damage models for brittle and ductile failure are applied to a space structure by Windisch et al. Problems of fatigue crack initiation and propagation are discussed in papers of Ghidini and Zhang et al. The latter specifically deals with problems of crack retardation due to bonded crack retarders. In a theoretical work, Wyart et al. show the advantages and future prospective of the substructure finite element method with respect to its application to thin walled components.
The Guest Editors wish to thank the authors for preparing their manuscripts for publication and the referees for their critical, yet constructive review of the papers. It is their wish, that the papers will contribute to the further development of the assessment methodology for thin-walled structures and that they will stimulate the communication between users and researchers.
One of the aims of the workshop was to honour the influential work performed over the last decades on the integrity of pre-damaged thin-walled structures by Prof. Karl-Heinz Schwalbe, former head of the Institute for Materials Research at GKSS Research Centre, and one of the present Editors-in-Chief of Engineering Fracture Mechanics.
DOI Link to Publication