This book provides a systematic and standardized approach based on the authors’ over 30 years of research experience with weight function methods, as well as the relevant literature. Fracture mechanics has become an indispensable tool for the design and safe operation of damage-tolerant structures in many important technical areas. The stress intensity factor—the characterizing parameter of the crack tip field—is the foundation of fracture mechanics analysis. The weight function method is a powerful technique for determining stress intensity factors and crack opening displacements for complex load conditions, with remarkable computational efficiency and high accuracy. The book presents the theoretical background of the weight function methods, together with a wealth of analytical weight functions and stress intensity factors for two- and three-dimensional crack geometries; many of these have been incorporated into national, international standards and industrial codes of practice. The accuracy of the results is rigorously verified, and various sample applications are provided. Accordingly, the book offers an ideal reference source for graduate students, researchers, and engineers whose work involves fracture and fatigue of materials and structures, who need not only stress intensity factors themselves but also efficient and reliable tools for obtaining them.

Fracture mechanics is an indispensible tool in the design and safe operation of damage tolerant structures. One of the essential elements in fracture mechanics based analysis is the stress intensity factor. This book provides a powerful theoretical background to the weight function method in fracture mechanics and numerous stress intensity factors. Part I gives a theoretical background and overview of the weight function method. Part II provides further details of the weight functions for various geometries and a large number of stress intensity factor solutions. Part II deals with the determination of crack opening displacements, Dugdale model solutions and crack opening areas.

In this book the authors describe methods for the calculation of weight functions. In the first part they discuss the accuracy and convergence behaviour of methods for one- and two-dimensional cracks, while in the second part they provide solutions for cracks subjected to mode-I and mode-II loading.

On Fracture Mechanics A major objective of engineering design is the determination of the geometry and dimensions of machine or structural elements and the selection of material in such a way that the elements perform their operating function in an efficient, safe and economic manner. For this reason the results of stress analysis are coupled with an appropriate failure criterion. Traditional failure criteria based on maximum stress, strain or energy density cannot adequately explain many structural failures that occurred at stress levels considerably lower than the ultimate strength of the material. On the other hand, experiments performed by Griffith in 1921 on glass fibers led to the conclusion that the strength of real materials is much smaller, typically by two orders of magnitude, than the theoretical strength. The discipline of fracture mechanics has been created in an effort to explain these phenomena. It is based on the realistic assumption that all materials contain crack-like defects from which failure initiates. Defects can exist in a material due to its composition, as second-phase particles, debonds in composites, etc. , they can be introduced into a structure during fabrication, as welds, or can be created during the service life of a component like fatigue, environment-assisted or creep cracks. Fracture mechanics studies the loading-bearing capacity of structures in the presence of initial defects. A dominant crack is usually assumed to exist.

The Boundary Integral Equation (BIE) method has occupied me to various degrees for the past twenty-two years. The attraction of BIE analysis has been its unique combination of mathematics and practical application. The EIE method is unforgiving in its requirement for mathe matical care and its requirement for diligence in creating effective numerical algorithms. The EIE method has the ability to provide critical inSight into the mathematics that underlie one of the most powerful and useful modeling approximations ever devised--elasticity. The method has even revealed important new insights into the nature of crack tip plastic strain distributions. I believe that EIE modeling of physical problems is one of the remaining opportunities for challenging and fruitful research by those willing to apply sound mathematical discipline coupled with phys ical insight and a desire to relate the two in new ways. The monograph that follows is the summation of many of the successes of that twenty-two years, supported by the ideas and synergisms that come from working with individuals who share a common interest in engineering mathematics and their application. The focus of the monograph is on the application of EIE modeling to one of the most important of the solid mechanics disciplines--fracture mechanics. The monograph is not a trea tise on fracture mechanics, as there are many others who are far more qualified than I to expound on that topic.

Local approaches to fatigue assessment are used to predict the structural durability of welded joints, to optimise their design and to evaluate unforeseen joint failures. This standard work provides a systematic survey of the principles and practical applications of the various methods. It covers the hot spot structural stress approach to fatigue in general, the notch stress and notch strain approach to crack initiation and the fracture mechanics approach to crack propagation. Seam-welded and spot-welded joints in structural steels and aluminium alloys are also considered.This completely reworked second edition takes into account the tremendous progress in understanding and applying local approaches which has been achieved in the last decade. It is a standard reference for designers, structural analysts and testing engineers who are responsible for the fatigue-resistant in-service behaviour of welded structures. - Completely reworked second edition of a standard work providing a systematic survey of the principles and practical applications of the various methods - Covers the hot spot structural stress approach to fatigue in general, the notch stress and notch strain approach to crack initiation and the fracture mechanics approach to crack propagation. - Written by a distinguished team of authors