Fatigue Design and Reliability


Book Description

This volume represents a selection of papers presented at the Third International Symposium on Fatigue Design, Fatigue Design 1998, held in Espoo, Finland, 26-29 May, 1998.One objective of this symposium series was to help bridge the gap that sometimes exists between researchers and engineers responsible for designing components against fatigue failure. The 21 selected papers provide an up-to-date survey of engineering practice and a preview of design methods that are advancing toward application. Reliability was selected as a key theme for FD'98. During the design of components and structures, it is not sufficient to combine mean material properties, average usage parameters, and pre-selected safety factors. The engineer must also consider potential scatter in material properties, different end users, manufacturing tolerances and uncertainties in fatigue damage models. Judgement must also be made about the consequences of potential failure and the required degree of reliability for the structure or component during its service life. Approaches to ensuring reliability may vary greatly depending on the structure being designed. Papers in this volume intentionally provide a multidisciplinary perspective on the issue. Authors represent the ground vehicle, heavy equipment, power generation, ship building and other industries. Identical solutions cannot be used in all cases because design methods must always provide a balance between accuracy and simplicity. The point of balance will shift depending on the type of input data available and the component being considered.




Fatigue Design


Book Description

Fatigue Design, Second Edition discusses solutions of previous problems in fatigue as controlled by their particular conditions. The book aims to demonstrate the limitations of some methods and explores the realism and validity of the resulting solutions. The text is comprised of four chapters that tackle a specific area of concern. Chapter 1 provides the introduction and covers the scope, level, and limitations of the book. Chapter 2 deals with the characteristics of design approach, and Chapter 3 talks about the prediction of fatigue life. The last chapter discusses the general factors in fatigue. The book will be of great interest to researchers and professionals concerned with fatigue analysis, such as engineers and designers.




Fatigue Testing and Analysis


Book Description

Fatigue Testing and Analysis: Theory and Practice presents the latest, proven techniques for fatigue data acquisition, data analysis, and test planning and practice. More specifically, it covers the most comprehensive methods to capture the component load, to characterize the scatter of product fatigue resistance and loading, to perform the fatigue damage assessment of a product, and to develop an accelerated life test plan for reliability target demonstration. This book is most useful for test and design engineers in the ground vehicle industry. Fatigue Testing and Analysis introduces the methods to account for variability of loads and statistical fatigue properties that are useful for further probabilistic fatigue analysis. The text incorporates and demonstrates approaches that account for randomness of loading and materials, and covers the applications and demonstrations of both linear and double-linear damage rules. The reader will benefit from summaries of load transducer designs and data acquisition techniques, applications of both linear and non-linear damage rules and methods, and techniques to determine the statistical fatigue properties for the nominal stress-life and the local strain-life methods. - Covers the useful techniques for component load measurement and data acquisition, fatigue properties determination, fatigue analysis, and accelerated life test criteria development, and, most importantly, test plans for reliability demonstrations - Written from a practical point of view, based on the authors' industrial and academic experience in automotive engineering design - Extensive practical examples are used to illustrate the main concepts in all chapters




Fatigue Design of Steel and Composite Structures


Book Description

This volume addresses the specific subject of fatigue, a subject not familiar to many engineers, but still relevant for proper and good design of numerous steel structures. It explains all issues related to the subject: Basis of fatigue design, reliability and various verification formats, determination of stresses and stress ranges, fatigue strength, application range and limitations. It contains detailed examples of applications of the concepts, computation methods and verifications.




Fatigue Design of Aluminum Components and Structures


Book Description

Focusing on the design challenges associated with using aluminum in such fatigue-critical applications as highway infrastructures, transportation vehicles, automotive suspension systems, and aircraft and machine parts, this reference gives the data and guidelines that mechanical and civil design engineers need to meet these challenges head on.




Fatigue Life Analyses of Welded Structures


Book Description

Avoiding or controlling fatigue damage is a major issue in the design and inspection of welded structures subjected to dynamic loading. Life predictions are usually used for safe life analysis, i.e. for verifying that it is very unlikely that fatigue damage will occur during the target service life of a structure. Damage tolerance analysis is used for predicting the behavior of a fatigue crack and for planning of in-service scheduled inspections. It should be a high probability that any cracks appearing are detected and repaired before they become critical. In both safe life analysis and the damage tolerance analysis there may be large uncertainties involved that have to be treated in a logical and consistent manner by stochastic modeling. This book focuses on fatigue life predictions and damage tolerance analysis of welded joints and is divided into three parts. The first part outlines the common practice used for safe life and damage tolerance analysis with reference to rules and regulations. The second part emphasises stochastic modeling and decision-making under uncertainty, while the final part is devoted to recent advances within fatigue research on welded joints. Industrial examples that are included are mainly dealing with offshore steel structures. Spreadsheets which accompany the book give the reader the possibility for hands-on experience of fatigue life predictions, crack growth analysis and inspection planning. As such, these different areas will be of use to engineers and researchers.




SAE Fatigue Design Handbook


Book Description

Covers, in a single source, current technologies and procedures on all of the major elements of fatigue design. Intended as a handbook for industrial use, this book describes the major elements of the fatigue design process and how those elements must be tied together in a comprehensive product evaluation. Using this handbook will save the design engineer time, while ensuring understanding of the important elements of the fatigue design process.




Safety Factors and Reliability: Friends or Foes?


Book Description

Have you ever wondered where the safety factors come from? Why is it that deterministic analysis has reached a very sophisticated level, but in the end empirical factors are still needed? Is there a way to select them, rather than assigning them arbitrarily as is often done? This book clearly shows that safety factors are closely related with the reliability of structures, giving yet another demonstration of Albert Einstein's maxim that "It is incomprehensible that Nature is comprehensible". The book shows that the safety factors are much more comprehensible if they are seen in a probabilistic context. Several definitions of the safety factors are given, analytical results on insightful numbers are presented, nonprobabilistic safety factors are shown, as well as their estimates derived by the inequalities of Bienayme, Markov, Chebushev and Camp-Meidell. A special chapter is devoted to important contributions by Japanese experts. This volume will help to critically re-think the issue of safety factors, which can create a false feeling of security. The deterministic paradigm can be enhanced by incorporating probabilistic concepts wisely where they are needed without treating all variables as probabilistic ones. The book shows that there is a need of their integration rather than separation. This book is intended for engineers, graduate students, lecturers and researchers.




Fatigue and Fracture Reliability Engineering


Book Description

Fatigue and Fracture Reliability Engineering is an attempt to present an integrated and unified approach to reliability determination of fatigue and fracture behaviour, incorporating probability, statistics and other related areas. A series of original and practical approaches, are suggested in Fatigue and Fracture Reliability Engineering, including new techniques in determining fatigue and fracture performances. It also carries out an investigation into static and fatigue properties, and into the failure mechanisms of unnotched and notched CFR composite laminates with different lay-ups to optimize the stacking sequence effect. Further benefits include: a novel convergence-divergence counting procedure to extract all load cycles from a load history of divergence-convergence waves; practical scatter factor formulae to determine the safe fatigue crack initiation and propagation lives from the results of a single full-scale test of a complete structure; and a nonlinear differential kinetic model for describing the dynamical behaviour of an atom at a fatigue crack tip. Fatigue and Fracture Reliability Engineering is intended for practising engineers in marine, civil construction, aerospace, offshore, automotive and chemical industries. It is also useful reading for researchers on doctoral programmes, and is appropriate for advanced undergraduate and postgraduate programmes in any mechanically-oriented engineering discipline.




Uncertainty Modeling in Finite Element, Fatigue and Stability of Systems


Book Description

The functionality of modern structural, mechanical and electrical or electronic systems depends on their ability to perform under uncertain conditions. Consideration of uncertainties and their effect on system behavior is an essential and integral part of defining systems. In eleven chapters, leading experts present an overview of the current state of uncertainty modeling, analysis and design of large systems in four major areas: finite and boundary element methods (common structural analysis techniques), fatigue, stability analysis, and fault-tolerant systems. The content of this book is unique; it describes exciting research developments and challenges in emerging areas, and provide a sophisticated toolbox for tackling uncertainty modeling in real systems.