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Ssc-405 Fatigue Resistant Detail Design Guide for Ship Structures

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NTIS # PB99-159931 SSC-405 FATIGUE RESISTANT DETAIL DESIGN GUIDE FOR SHIP STRUCTURES This document has been approved For public release and sale; its Distribution is unlimited SHIP STRUCTURE COMMITTEE 1999 Ship Structure Committee RADM Robert C. North U. S. Coast Guard Assistant Commandant, Marine Safety and Environmental Protection Chairman, Ship Structure Committee Mr. Robert McCarthy Dr. Donald Liu Director, Senior Vice President Survivability and Structural Integrity Group American Bureau of Shipping Naval Sea Systems Command Mr. Marc Lasky Mr. Bud Streeter Director, Office of Ship Construction Director General, Marine Safety, Maritime Administration Safety & Security Transport Canada Mr. Thomas Connors Dr. Neil Pegg Director of Engineering Group Leader - Structural Mechanics Military Sealift Command Defence Research & Development Canada - Atlantic CONTRACTING OFFICER TECHNICAL REP. EXECUTIVE DIRECTOR Mr. Chao Lin / MARAD Lieutenant William A. Nabach TBD / NAVSEA U. S. Coast Guard Mr. Robert Sedat / USCG SHIP STRUCTURE SUB-COMMITTEE AMERICAN BUREAU OF SHIPPING DEFENCE RESEARCH & DEVELOPMENT ATLANTIC Mr. Glenn Ashe Mr. Layton Gilroy Mr. John F. Conlon Mr. John Porter Mr. Phil Rynn LCDR Stephen Gibson Mr. William Hanzalek Dr. David Stredulinsky MARITIME ADMINISTRATION MILITARY SEALIFT COMMAND Mr. Chao Lin Mr. Edward Meade Mr. Rick A. Anderson Mr. Jeffery E. Beach Mr. Michael W. Touma NAVAL SEA SYSTEMS COMMAND TRANSPORT CANADA Mr. W. Thomas Packard Mr. Andre Taschereau Mr. Edward E. Kadala Mr. Justus Benckhuysen Mr. Allen H. Engle Mr. James Reid Mr. Charles L. Null UNITED STATES COAST GUARD Captain Mark VanHaverbeke Mr. Walt Lincoln Mr. Walt Lincoln CDR Ray Petow Member Agencies: Address Correspondence to: Amen'can Bureau of Shipping Executive Director Defence Research Establishment Atlantic Ship Structure Committee Maritime Administration U.S. Coast Guard (G-MSE/SSC) Military Sea/ift Command 2100 Second Street. S.W. Naval Sea Systems Command Washington, D.C. 20593-0001 Transport Canada Ph: (202) 267-0003 United States Coast Guard Ship Email: [email protected] Structure Committee An lnteragency Adviso,y Committee SR-1386 SSC-405 August 6, 1999 FATIGUE RESISTANT DETAIL DESIGN GUIDE FOR smp STRUCTURES This Guide is a result of a 1995 Ship Structure Committee Symposium in Washington, DC, at which it was recognized that practicing naval architects required help in applying fatigue design research and development results. This Guide consolidates the state-of-the-art in ship structural detail fatigue design. The information in the Guide is presented in four sections, starting with an overview of the fatigue design problem and related issues. ·The second includes a catalogue of typical structural details for commercial and combatant ship types, with suggested structural improvements for fatigue life extension. This, along with a brief discussion of fabrication issues, represents the "Level 1" approach to ship structure fatigue design. The third section of the report presents analytical procedures for fatigue based design of structural details. Load, stress and fatigue analysis procedures are -presented at two levels of complexity, "Level 21' and "Level 3". The simplified Level 2 approach makes use of Classification Society rules and analytical methods, whereas, the spectral Level 3 approach explicitly considers vessel operational profiles and wave climates in statistical load estimation and makes use of FE models for stress analysis. Both the Level 2 and 3 approaches are based on a "hot spot" stress approach using Miner's rule in either a discrete or continuous fomi. The final section of the Gui provides worked fatigue design examples to demonstrate the concepts p ted in the previo sections. Technical Report Documentation Form 1. Report No. 2. Government Accession No. 3. Recipient’s Catalogue No. SR-1386 4. Title and Subtitle 5. Report Date March 1999 Fatigue-Resistant Detail Design Guide for Ship Structures 6. Performing Organization Document No. 7. Author(s) 8. Performing Organization Report No. I.F. Glen, A. Dinovitzer, R.B. Paterson, L. Luznik, C. Bayley 4714C.FR 9. Performing Agency Name and Address 10. Work Unit No. (TRAIS) Fleet Technology Limited 311 Legget Drive 11. Contract or Grant No. Kanata, Ontario (CANADA) K2K 1Z8 PO # 97-0046 12. Sponsoring Agency Name and Address 13. Type of Publication and Period Covered Ship Structure Committee Final Report c/o US Coast Guard 2100 Second Street, SW 14. Sponsoring Agency Code Washington, DC 20593-0001 15. Supplementary Notes 16. Abstract This Guide is a result of a 1995 Ship Structures Committee Symposium in Washington, at which it was recognized that practicing naval architects required help in applying fatigue design research and development results. This Guide consolidates the state-of-the-art in ship structural detail fatigue design. The information in the Guide is presented in four sections, starting with an overview of the fatigue design problem and related issues. The second section includes a catalogue of typical structural details for commercial and combatant ship types, with suggested structural improvements for fatigue life extension. This, along with a brief discussion of fabrication issues, represents the “Level 1” approach to ship structure fatigue design. The third section of the report presents analytical procedures for fatigue based design of structural details. Load, stress and fatigue analysis procedures are presented at two levels of complexity, “Level 2” and “Level 3”. The simplified Level 2 approach makes use of Classification Society rules and analytical methods, whereas, the spectral Level 3 approach explicitly considers vessel operational profiles and wave climates in statistical load estimation and makes use of FE models for stress analysis. Both the Level 2 and 3 approaches are based on a “hot spot” stress approach using Miner’s rule in either a discrete or continuous form. The final section of the Guide provides worked fatigue design examples to demonstrate the concepts presented in the previous sections. 17. Key Words 18. Distribution Statement fatigue, ship structures, structural details, design 19. Security Classif. (of this report) 20. SECURITY CLASSIF. (of this page) 21. No. of Pages 22. Price Unclassified Unclassified Form DOT F 1700.7 (8/72) Reproduction of form and completed page is authorized Fatigue-Resistant Detail Design Guide for Ship Structures ii ACKNOWLEDGEMENTS The preparation of this Guide has been a mammoth task, relative to the resources available. At the outset, the terms of the contract were that no new work was to be developed – the Guide was to be a compilation of existing, published work. In the process of the project, it became clear that some new ground was being broken in the practical application of the published work to real ship design problems. The authors have drawn heavily on the published work of the Classification Societies, and in particular, Lloyd’s Register of Shipping, the American Bureau of Shipping and Det Norske Veritas. FTL and the SSC wish to express their great appreciation to these Societies for permission to use this material. The authors also wish to thank their panel of advisors: Dr. Roger Basu, Dr. David Sucharski, David Dalgleish and Dr. Alan Benison, whose function was to view this Guide from the viewpoint of practicing designers and shipbuilders. We also wish to acknowledge the input of Dr. Richard Yee who commenced the work, and Dr. Harold Reemsnyder who contributed his expertise and critique. Finally, but by no means least of all, we thank the SSC’s Project Technical Committee under the Chairmanhsip of Nash Gifford, Bill Siekeirka and Lt. Tom Miller, USCG, for their input to the project and their patience for the delayed schedule. We hope the result has justified the wait. Fatigue-Resistant Detail Design Guide for Ship Structures iii TABLE OF CONTENTS PART A – FATIGUE DESIGN GUIDE OVERVIEW A.1 INTRODUCTION A-1 A.2 OBJECTIVE A-1 A.3 BACKGROUND TO FATIGUE IN SHIP STRUCTURES A-2 A.3.1 Metal Fatigue Process in Steel Ships A-2 A.3.2 Historical Treatment of Metal Fatigue in Steel Ships A-4 A.4 SCOPE OF THE GUIDE A-6 A.4.1 Layout of the Guide A-6 A.4.2 Application of the Guide as a Design Aid A-7 A.5 REFERENCES A-10 PART B – CATALOGUE OF FATIGUE RESISTANT DETAILS B.1 INTRODUCTION B-1 B.1.1 Background B-1 B.1.2 Objective B-1 B.1.3 Scope B-3 B.2 CRITICAL AND NON-CRITICAL DETAILS B-4 B.2.1 Consequences of Failure (Structural Function) B-4 B.2.2 Probability of Failure (Fatigue Resistance) B-5 B.2.3 Warship Details B-5 B.3 CATALOGUE TERMINOLOGY B-5 B.4 LAYOUT OF THE CATALOGUE B-6 B.4.1 Introduction B-6 B-5 FATIGUE RESISTANT DETAIL CATALOGUE B-12 B.5.1 Tanker Structure Details B-12 B.5.2 Bulk Carrier Structure Details B-34 B.5.3 Container Ship Structure Details B-52 B.5.4 Warship Structure Details B-61 Fatigue-Resistant Detail Design Guide for Ship Structures iv TABLE OF CONTENTS (continued) B.6 “GOOD” DESIGN, CONSTRUCTION AND WELDING PRACTICES TO B-89 ENHANCE FATIGUE PERFORMANCE B.6.1 Introduction B-89 B.6.2 Detail Design B-89 B.6.3 Construction and Welding Practice B-91 B.6.4 Residual Stresses B-92 B.6.5 Weld Toe Dressing Treatments B-93 B.7 REFERENCES B-94 PART C – FATIGUE STRENGTH ASSESSMENT C.1 INTRODUCTION C-1 C.1.1 Background C-1 C.1.2 Objective C-1 C.1.3 Scope C-1 C.2 FATIGUE ANALYSIS PROCEDURES C-2 C.2.1 Overview C-2 C.2.2 Commentary C-2 C.2.2.1 Intended Applications C-2 C.2.2.2 Design Life C-2 C.2.2.3 Non-linearities C-4 C.2.3 Design Codes and Criteria C-4 C.3 LOAD ANALYSIS C-5 C.3.1 Determination
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