Fracture And Fatigue Of Welded Joints And Structures

The failure of any welded joint is at best inconvenient and at worst can lead to catastrophic accidents. Fracture and fatigue of welded joints and structures analyses the processes and causes of fracture and fatigue, focusing on how the failure of welded joints and structures can be predicted and minimised in the design process. Part one concentrates on analysing fracture of welded joints and structures, with chapters on constraint-based fracture mechanics for predicting joint failure, fracture assessment methods and the use of fracture mechanics in the fatigue analysis of welded joints. In part two, the emphasis shifts to fatigue, and chapters focus on a variety of aspects of fatigue analysis including assessment of local stresses in welded joints, fatigue design rules for welded structures, k-nodes for offshore structures and modelling residual stresses in predicting the service life of structures. With its distinguished editor and international team of contributors, Fracture and fatigue of welded joints and structures is an essential reference for mechanical, structural and welding engineers, as well as those in the academic sector with a research interest in the field. Analyses the processes and causes of fracture and fatigue, focusing predicting and minimising the failure of welded joints in the design process Assesses the fracture of welded joints and structure featuring constraint-based fracture mechanics for predicting joint failure Explores specific considerations in fatigue analysis including the assessment of local stresses in welded joints and fatigue design rules for welded structures

These recommendations present general methods for the assessment of fatigue damage in welded components, which may affect the limit states of a structure, such as ultimate limit state and serviceability limited state. Fatigue resistance data is given for welded components made of wrought or extruded products of ferritic/pearlitic or banitic structural steels up to fy = 700 Mpa and of aluminium alloys commonly used for welded structures.

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

Fatigue is a mechanism of failure which involves the formation and growth of cracks under the action of repeated stresses. Ultimately, a crack may propagate to such an extent that total fracture of the member may occur. To avoid fatigue it is essential to design the structure with inherent fatigue strength. However, fatigue strength for variable amplitude loading is not a constant material property and any calculations are necessarily built on a number of assumptions. Cumulative damage of welded joints explores the wealth of research in this important field and its implications for the design and manufacture of welded components. After an Introduction, chapter two introduces the constant amplitude database, which contains results obtained in test conditions and which forms the basis of the basic S-N curves for various types of joint. Chapter three discusses the influence of residual stresses which can have a marked effect on fatigue behaviour. Chapter four explores variable amplitude loading and the problem of how information from laboratory tests, obtained under constant amplitude conditions, can be applied to the design of structures for service conditions. This problem is further investigated in the next chapter which is devoted to two and three level load testing. Chapters six, seven and eight look at the influence that the variety of variable loading spectra can have on fatigue strength, whether narrow or wide band loading or cycles of small stress range. Taking all of this knowledge, chapter nine discusses structure designs. Cumulative damage of welded joints is a comprehensive source of invaluable information for welding engineers, supervisors, inspection personnel and designers. It will also be of great interest for academics working in the fields of structural and mechanical engineering. Covers the wealth of research in the field of fatigue strength and its role in the design and manufacture of welded components Invaluable reference source for welding engineers, supervisors, inspection personnel and designers

Fifteen papers from a symposium held in Sparks, Nev., April 1988. They cover: low and high cycle fatigue, fatigue crack growth, corrosion fatigue, fracture toughness testing, and wide-plate testing. Annotation copyright Book News, Inc. Portland, Or.

The key to avoidance of fatigue, which is the main cause of service failures, is good design. In the case of welded joints, which are particularly susceptible to fatigue, design rules are available. However, their effective use requires a good understanding of fatigue and an appreciation of problems concerned with their practical application. Fatigue strength of welded structures has incorporates up-to-date design rules with high academic standards whilst still achieving a practical approach to the subject. The book presents design recommendations which are based largely on those contained in recent British standards and explains how they are applied in practice. Attention is also focused on the relevant aspects of fatigue in welded joints which are not yet incorporated in codes thus providing a comprehensive aid for engineers concerned with the design or assessment of welded components or structures. Background information is given on the fatigue lives of welded joints which will enable the engineer or student to appreciate why there is such a contrast between welded and unwelded parts, why some welded joints perform better than others and how joints can be selected to optimise fatigue performance.

Avoiding or controlling fatigue damage is a major issue in thedesign and inspection of welded structures subjected to dynamicloading. Life predictions are usually used for safe life analysis,i.e. for verifying that it is very unlikely that fatigue damagewill occur during the target service life of a structure. Damagetolerance analysis is used for predicting the behavior of a fatiguecrack and for planning of in-service scheduled inspections. Itshould be a high probability that any cracks appearing are detectedand repaired before they become critical. In both safe lifeanalysis and the damage tolerance analysis there may be largeuncertainties involved that have to be treated in a logical andconsistent manner by stochastic modeling. This book focuses on fatigue life predictions and damage toleranceanalysis of welded joints and is divided into three parts. Thefirst part outlines the common practice used for safe life anddamage tolerance analysis with reference to rules and regulations.The second part emphasises stochastic modeling and decision-makingunder uncertainty, while the final part is devoted to recentadvances within fatigue research on welded joints. Industrialexamples that are included are mainly dealing with offshore steelstructures. Spreadsheets which accompany the book give the readerthe possibility for hands-on experience of fatigue lifepredictions, crack growth analysis and inspection planning. Assuch, these different areas will be of use to engineers andresearchers.