Fatigue Analysis of Welded Components
Designer's Guide to the Structural Hot-Spot Stress Approach
Published on 27. September 2006
Book
Paperback/Softback
56 pages
978-1-84569-124-0 (ISBN)
Description
This report provides background and guidance on the use of the structural hot spot stress approach to the fatigue design of welded components and structures. It complements the IIW recommendations for 'Fatigue Design of Welded Joints and Components' and extends the information provided in the IIW recommendations on 'Stress Determination for Fatigue Analysis of Welded Components'. This approach is applicable to cases of potential fatigue cracking from the weld toe. It has been in use for many years in the context of tubular joints. The present report concentrates on its extension to structures fabricated from plates and non-tubular sections.
Following an explanation of the structural hot spot stress, its definition and its relevance to fatigue, the authors describe methods for its determination. Stress determination from both finite element analysis and strain gauge measurements is considered. Parametric formulae for calculating stress increases due to misalignment and structural discontinuities are also presented. Special attention is paid to the use of finite element stress analysis and guidance is given on the choice of element type and size for use with either solid or shell elements. Design S-N curves for use with the structural hot spot stress are presented for a range of weld details. Finally, practical application of the recommendations is illustrated in two case studies involving the fatigue assessment of welded structures using the structural hot spot stress approach.
Following an explanation of the structural hot spot stress, its definition and its relevance to fatigue, the authors describe methods for its determination. Stress determination from both finite element analysis and strain gauge measurements is considered. Parametric formulae for calculating stress increases due to misalignment and structural discontinuities are also presented. Special attention is paid to the use of finite element stress analysis and guidance is given on the choice of element type and size for use with either solid or shell elements. Design S-N curves for use with the structural hot spot stress are presented for a range of weld details. Finally, practical application of the recommendations is illustrated in two case studies involving the fatigue assessment of welded structures using the structural hot spot stress approach.
More details
Series
Language
English
Place of publication
Cambridge
United Kingdom
Publishing group
Elsevier Science & Technology
Target group
Professional and scholarly
Weight
180 gr
ISBN-13
978-1-84569-124-0 (9781845691240)
Copyright in bibliographic data and cover images is held by Nielsen Book Services Limited or by the publishers or by their respective licensors: all rights reserved.
Schweitzer Classification
Other editions
Additional editions
E. Niemi | W. Fricke | S. J. Maddox
Fatigue Analysis of Welded Components
Designer's Guide to the Structural Hot-Spot Stress Approach
E-Book
09/2006
Woodhead Publishing
€149.00
Available for download
Persons
Professor Erkki Niemi is Emeritus Professor of Steel Structures in Lappeenranta University of Technology, Finland. Professor Dr-Ing. Wolfgang Fricke is Head of the Institute for Ship Structural Design and Analysis at Hamburg University of Technology, Germany. Stephen J. Maddox is a Consultant with The Welding Institute (TWI) in the UK and is also Visiting Professor in the Department of Mechanical Engineering at the University of Strathclyde, UK.
Content
Preface
Abstract
1. Introduction
1.1 General
1.2 Safety aspects
2. The Structural Hot Spot Stress Approach to Fatigue Analysis
2.1 Field of application
2.2 Types of hot spot
2.3 Definition of the structural stress at a Type 'a' hot spot
2.4 Use of stress concentration factors
2.5 Effect of component size on the fatigue resistance
3. Experimental Determination of the Structural Hot Spot Stress
3.1 General
3.2 Type 'a' hot spots
3.3 Type 'b' hot spots
4. Structural Hot Spot Stress Determination Using Finite Element Analysis
4.1 General
4.2 Choice of element type
4.3 Methods for determination of structural hot spot stress
4.4 Use of relatively coarse element meshing for analysing Type 'a' hot spots
4.5 Use of relatively fine element meshing for analysing Type 'a' hot spots
4.6 Modelling fillet welds in shell element models for analysing Type 'a' hot spots
4.7 Analysis of Type 'b' hot spots
5. Parametric Formulae
5.1 Misalignment
5.2 Structural discontinuities
6. Structural Hot Spot S-N Curves
6.1 General principles
6.2 Recommended S-N curves
7. Case Study 1: Box Beam of a Railway Wagon
7.1 Introduction
7.2 Materials and methods
7.3 Results
7.4 Discussion and conclusions
8. Case Study 2: Hatch Corner Design for Container Ships
8.1 Introduction
8.2 Materials and methods
8.3 Fatigue assessment
8.4 Conclusion
References
Appendix 1: Symbols
Appendix 2: A2.4 References
A2.1 Need for enhanced accuracy
A2.2 Alternative procedures for enhanced accuracy
A2.3 Quadratic extrapolation
Appendix 3: References
Appendix 4: Hot Spot S-N Curves for Welded Aluminium Components
Abstract
1. Introduction
1.1 General
1.2 Safety aspects
2. The Structural Hot Spot Stress Approach to Fatigue Analysis
2.1 Field of application
2.2 Types of hot spot
2.3 Definition of the structural stress at a Type 'a' hot spot
2.4 Use of stress concentration factors
2.5 Effect of component size on the fatigue resistance
3. Experimental Determination of the Structural Hot Spot Stress
3.1 General
3.2 Type 'a' hot spots
3.3 Type 'b' hot spots
4. Structural Hot Spot Stress Determination Using Finite Element Analysis
4.1 General
4.2 Choice of element type
4.3 Methods for determination of structural hot spot stress
4.4 Use of relatively coarse element meshing for analysing Type 'a' hot spots
4.5 Use of relatively fine element meshing for analysing Type 'a' hot spots
4.6 Modelling fillet welds in shell element models for analysing Type 'a' hot spots
4.7 Analysis of Type 'b' hot spots
5. Parametric Formulae
5.1 Misalignment
5.2 Structural discontinuities
6. Structural Hot Spot S-N Curves
6.1 General principles
6.2 Recommended S-N curves
7. Case Study 1: Box Beam of a Railway Wagon
7.1 Introduction
7.2 Materials and methods
7.3 Results
7.4 Discussion and conclusions
8. Case Study 2: Hatch Corner Design for Container Ships
8.1 Introduction
8.2 Materials and methods
8.3 Fatigue assessment
8.4 Conclusion
References
Appendix 1: Symbols
Appendix 2: A2.4 References
A2.1 Need for enhanced accuracy
A2.2 Alternative procedures for enhanced accuracy
A2.3 Quadratic extrapolation
Appendix 3: References
Appendix 4: Hot Spot S-N Curves for Welded Aluminium Components