CLASS GUIDELINE Fatigue Assessment Of Ship Structures

Academia.edu no longer supports Internet Explorer.

To browse Academia.edu and the wider internet faster and more securely, please take a few seconds to upgrade your browser.

Log InSign Up

• Log In
• Sign Up
• more
• • About
  • Press
  • Papers
  • Terms
  • Privacy
  • Copyright
  • We're Hiring!
  • Help Center
  • less

Outline

keyboard_arrow_downTitleAbstractSection 1 General 1 IntroductionMethods for Fatigue AssessmentMethods for Stress CalculationSection 2 Fatigue Capacity 1 IntroductionBase Material and Free Plate EdgesThickness Effect of Welds in Fe AnalysisThickness Effect of Base MaterialMaterial FactorComponent Stochastic AnalysisFull Stochastic AnalysisIntroductionBase Material Free Plate EdgesLimitation to Hot Spot Stress ApproachSection 8 Detail Design Standard 1 IntroductionDetail Design Standard for Different Ship TypesGuidance for Omission of Fatigue AnalysisMethod BVerification of Analysis Methodologydownload

Download Free PDF

Download Free PDFCLASS GUIDELINE Fatigue assessment of ship structuresTaner Derelioğluvisibility

…

description

236 pages

descriptionSee full PDFdownloadDownload PDF bookmarkSave to LibraryshareShareclose

Sign up for access to the world's latest research

Sign up for freearrow_forwardcheckGet notified about relevant paperscheckSave papers to use in your researchcheckJoin the discussion with peerscheckTrack your impact

Abstract

AI

This guideline provides a comprehensive approach to assessing the fatigue life of ship structures, emphasizing the importance of updated calculations, test configurations, and stress factors. Key changes include corrected formulas for fatigue life predictions, modified stress concentration factors, and detailed methodologies for evaluating local stiffener bending and general ship structural integrity under varying loading conditions.

... Read more

Related papers

Redistribution of initial residual stresses in ship structural details and its effect on fatigueAnders Ulfvarson

Marine Structures, 1995

Explicit fatigue analysis of welded structures is mostly based on the stress range philosophy, which implies that high residual stresses from the welding process are always present. The structural analysis for the design of ships will normally consider only some of the largest quasi-static loads that the s~ip will experience in its lifetime. The effects of the high frequency loads responsible for fatigue damage are not described and analysed, as is done in most civil engineering and offshore applications. Ship structural details are designed to sustain fatigue loading by an implicit method where long term experience has selected successful design. This study shows that residual stresses are frequently redistributed in cut-outs and openings of tanker webframes and that the resulting residual stress conditions are predictable. Different assumptions of the initial residual stress fieM are made and redistribution due to sea loads is studied with non-linear finite element analysis (FEA ). Examples chosen for the investigation are flame cut edges in a conventional tanker webframe. It is shown that during each voyage local yielding will occur at the most fatigue-sensitive notches in the studied webframe. High stress ranges will cause considerable redistribution of the initial residual stress field. Locations with high tensile as well as compressive mean stresses can be detected. For cut-outs, geometrical optimisation by variation of the curvature is made possible. A reduction of damage is demonstrated for a specific notch in the studied webframe by a Palmgren-&Iiner damage calculation. A comparison of different approaches to calculate the damage has also been made showing significant differences.

downloadDownload free PDFView PDFchevron_rightFatigue Problems In Ship StructureJanusz Kozak

WIT Transactions on the Built Environment, 1999

Fatigue strength of ship structure is one of the components of reliability of ship as a mean of transport. Majority of fatigue strength assessment proposals given by classification societies are based on use of characteristics of typical joints or designs of hull construction given if form the Wohler curves. More accuracy calculation will be done if more adequate Wohler curve to calculate the problem will be applied. To gather wide spectrum of fatigue properties of typical ship hull nodal points fatigue tests should be performed and their results have to be systematised. Paper show an exemplary of systematic fatigue tests result as well as way of their systematisation.

downloadDownload free PDFView PDFchevron_rightStrength Assessment of Aged Fore-End Transverse Bulkhead in Bulk CarriersMohamed A Mosaad

11th International Conference on Marine Sciences and Techonologies, Black Sea 2012, ISSN 1314 - 0957& Port Said Engineering Research Journal, PSERJ, 2012, Volume 17 No. 1 pp: 175:179, 2012

Ship structures while in service are likely to be subjected to age deterioration which had actually caused catastrophic structural or total loss especially for bulk carriers. This had implied the need to develop advanced technologies which can allow for proper management and control of such age related deterioration. Recently, IMO and class societies have developed rules and regulations utilizing risk-based methods. The Formal Safety Assessment (FSA) is an example of such developments. In this paper a finite element model has been established by using ship structural analysis program for fore-end bulkhead of an existing bulk carrier which is being subjected to SOLAS XII as a risk control option of formal safety assessment. The main aim of the finite element model is to assess the strength characteristics of the structural members during service time with the reduction of bulkhead plating thickness due to age deterioration according to a recommended corrosion model and estimated corrosion rates. The insights developed from the present study are useful for finding a proper management for structural repair with consideration of corrosion wastage.

downloadDownload free PDFView PDFchevron_rightReliability‐Based Design Guidelines for Fatigue of Ship StructuresBilal Ayyub

Naval Engineers Journal, 2002

ABSTRACTMarine and offshore structures are subjected to fatigue loadings primarily due to the action of seawater waves and the sea environment in general. The load cycles in such an environment can be in the order of a million cycles per year. Fatigue failures in these structures can take place at sites of high stress concentration that can be classified by two major categories: baseplate and weldments. The former includes locations of high stress concentration such as openings, sharp re‐entry corners, and plate edges. In general, the mechanisms behind these failures are described by the general approaches to fatigue life prediction as discussed in this paper. There are two major approaches for predicting fatigue life: (1) the S‐N curve approach and (2) the fracture mechanics (FM) approach. The S‐N curve approach is based on experimental measurement of fatigue life in terms of cycles to failure for different loading levels and specimen geometries, while the fracture mechanics (FM) a...

downloadDownload free PDFView PDFchevron_rightEffect of stress concentration on fatigue of built-up I-shape membersGilbert Grondin

2010

Before high strength bolts became widely accepted, riveted joints were widely used in the construction of steel structures such as highway and railway bridges. These fasteners usually develop a low and unreliable level of pretension such that the joints are assumed to behave as bearing type connections. Under cyclic loading, and depending on the stress concentration around the fastener holes, fatigue failure can occur at nominal stresses significantly lower than in members with no stress concentration. The current design standards account for this by calculating the stress range on the net section and using fatigue category B and D to assess the fatigue life for bolted and riveted details, respectively. The net area used for the calculation of the stress range is based on the procedure proposed by Cochrane (the s 2 /4g rule), which is adequate for shear type failure. Tests have shown, however, that the Cochrane approach does not apply for fatigue failure since rupture does not take place in a ductile shear mode. An investigation into the effect of connection size and hole pattern on the fatigue resistance of built-up I-sections to gusset plate connections was carried out. An expression for the calculation of the stress concentration factor in built-up I-shape tension members was derived using the results of a parametric study based on a finite element study of the effect of member and joint geometry. A new fatigue category for these members is recommended.

downloadDownload free PDFView PDFchevron_rightFatigue capacity of side longitudinals in floating structuresInge Lotsberg

Marine Structures, 2005

Full-scale fatigue testing of five test specimens of side longitudinals of a ship/FPSO was carried out at the structural laboratories of DNV in Oslo. The main results from these tests are presented in this paper. The specimens have also been modelled by finite elements and some of the results from the most complex connections have been compared with measured data. The fatigue test results are compared with a hot spot S-N curve that is recommended for design of plated structures that are subjected to dynamic loading.

downloadDownload free PDFView PDFchevron_rightFatigue strength determination of ship structural jointsJanusz Kozak

Polish Maritime Research, 2011

Fatigue analysis of ship structures is a very complex problem. It results from many factors among which the following are most important: a) the material fatigue phenomenon itself has been not sufficiently recognized so far due to complex influence, on run of fatigue changes, of such factors as: kind of

downloadDownload free PDFView PDFchevron_rightEquivalent design wave approach for fatigue assessment of ship shaped structuresGaute Storhaug

2016

This paper presents a study carried out to investigate the use of the EDW method to calculate the fatigue life for stiffener end connections. Results from the EDW method is compared with results from a spectral analysis. Several ship types are included in the study. The results show that the accuracy of the EDW method is dependent on the roll damping and that the EDW method is more accurate for cases where the stress is dominated by one single load component. These findings are valid for all ship types, also for bulk carriers and tankers for which the method was originally constructed. It is not found that the EDW method is less accurate for container vessels or gas carriers.

downloadDownload free PDFView PDFchevron_rightUltimate strength analysis of stiffened plate variation on the longitudinal bulkhead of Double Hull Oil TankerChaewhan Rim

2019

Loongitudinal bulkhead also gives significant effect to the longitudinal strength of double hull oil tanker. The stiffened plate attached at the longitudinal bulkhead must have enough strength to wishtand the liquid oil which has an impact to the longitudinal bulkhead correspond to longitudinal strength. The objective of the present study is to analyze the ultimate strength of stiffened plate on the longitudinal bulkhead of double hull tanker. The small section of stiffened plate with attached plating at the longitudinal bulkhead is considered to the analyzed. The numerical analysis is adopted to analyze the model. The stiffened plate is variated with the distance in terms of model breadth. The boundary condition is applied to the model including axial compression load. The behavior of the model is represented by stress and deformation. For the simple analysis, the welding residual stress, crack, and initial imperfection are not taken. The result obtains by the numerical analysis is presented together with the behavior in term of stress and deformation.

downloadDownload free PDFView PDFchevron_rightTanker Transverse Strength Analysis--User's ManualLaurent Deschamps

1972

One of the most important goals of the Ship Structure Committee is the improvement of methods for design structures. This report is the third in Structure Committee reports on a project ment of an accurate, but less expensive, analysis method. and analysis of ship hull a sequence of four Ship directed toward developcomputer aided structural This report contains the User's Manual for the transverse strength analysis portion of the program.

downloadDownload free PDFView PDFchevron_rightSee full PDFdownloadDownload PDF

Loading Preview

Sorry, preview is currently unavailable. You can download the paper by clicking the button above.

Related papers

Background for New Revision of DNV-RP-C203 Fatigue Design of Offshore Steel StructuresInge Lotsberg

29th International Conference on Ocean, Offshore and Arctic Engineering: Volume 6, 2010

A type of loading causing a regular stress fluctuation with constant magnitudes of stress maxima and minima. Crack propagation rate: Amount of crack propagation during one stress cycle. Crack propagation threshold: Limiting value of stress intensity factor range below which the stress cycles are considered to be non-damaging. Eccentricity: Misalignment of plates at welded connections measured transverse to the plates. Effective notch stress: Notch stress calculated for a notch with a certain effective notch radius. Fatigue deterioration of a component caused by crack initiation and/or by the growth of cracks. Fatigue action: Load effect causing fatigue. Fatigue damage ratio: Ratio of fatigue damage at considered number of cycles and the corresponding fatigue life at constant amplitude loading. Fatigue life: Number of stress cycles at a particular magnitude required to cause fatigue failure of the component. Fatigue limit: Fatigue strength under constant amplitude loading corresponding to a high number of cycles large enough to be considered as infinite by a design code. Fatigue resistance: Structural detail's resistance against fatigue actions in terms of S-N curve or crack propagation properties. Fatigue strength: Magnitude of stress range leading to particular fatigue life. Fracture mechanics: A branch of mechanics dealing with the behaviour and strength of components containing cracks. Design Fatigue Factor: Factor on fatigue life to be used for design. Geometric stress: See "hot spot stress". Hot spot: A point in structure where a fatigue crack may initiate due to the combined effect of structural stress fluctuation and the weld geometry or a similar notch. Hot spot stress: The value of structural stress on the surface at the hot spot (also known as geometric stress or structural stress). Local nominal stress: Nominal stress including macro-geometric effects, concentrated load effects and misalignments, disregarding the stress raising effects of the welded joint itself. Local notch: A notch such as the local geometry of the weld toe, including the toe radius and the angle between the base plate surface and weld reinforcement. The local notch does not alter the structural stress but generates non-linear stress peaks. Macro-geometric discontinuity: A global discontinuity, the effect of which is usually not taken into account in the collection of standard structural details, such as large opening, a curved part in a beam, a bend in flange not supported by diaphragms or stiffeners, discontinuities in pressure containing shells, eccentricity in lap joints. Macro-geometric effect: A stress raising effect due to macro-geometry in the vicinity of the welded joint, but not due to the welded joint itself. Membrane stress: Average normal stress across the thickness of a plate or shell. Miner sum: Summation of individual fatigue damage ratios caused by each stress cycle or stress range block according to Palmgren-Miner rule. Misalignment: Axial and angular misalignments caused either by detail design or by fabrication. Nominal stress: A stress in a component, resolved, using general theories such as beam theory. Nonlinear stress peak: The stress component of a notch stress which exceeds the linearly distributed structural stress at a local notch. Notch stress: Total stress at the root of a notch taking into account the stress concentration caused by the local notch. Thus the notch stress consists of the sum of structural stress and non-linear stress peak. Notch stress concentration factor: The ratio of notch stress to structural stress. Paris' law: An experimentally determined relation between crack growth rate and stress intensity factor range. Palmgren-Miner rule: Fatigue failure is expected when the Miner sum reaches unity. Reference is also made to Chapter 9 on uncertainties). Rainflow counting: A standardised procedure for stress range counting.

downloadDownload free PDFView PDFchevron_rightŽelko: Simplified procedures for fatigue assessment of ship structuresBranko Blagojević

2015

Comparison of simplified procedures for fatigue assessment of ship structural details, used by classification societies, is presented. The basics of typical fatigue design approaches are described. In order to illustrate the capabilities and differences of the procedures, comparative study is performed on a bulk carrier built in Croatian shipyard in Split. Fatigue damage is calculated for a few longitudinals in connection with transverse structural elements. Longitudinals are located in the hopper tank, topside tank and double bottom of the bulk carrier. Fatigue damage of critical details is calculated applying current rules and guidelines of the classification societies Bureau Veritas, Germanischer Lloyd and Lloyd's Register of Shipping. The effect of a few input parameters on fatigue life is studied in a parameter variation including the shape parameter of the Weibull long-term stress distribution, structural misalignment and the effect of corrosion.

downloadDownload free PDFView PDFchevron_rightFatigue Yield of Ship StructuresKalman Žiha, Branko Blagojević

Volume 2: Structures, Safety and Reliability, 2009

The paper on the first place summarizes the fatigue yield approach as a cause-effect interaction between fatigue damage progression and fatigue endurance. Secondly it investigates the fatigue strength worsening on experimental S-N data and the load variability effects in shipbuilding. Next it applies the Classification Society's rule-based procedure for fatigue analysis of ship's structure that uses a simplified fatigue strength assessment method. The example elaborates fatigue yield effect on the seagoing operation of a double hull 47400 tdw tanker. At the end the paper recommends the procedure for assessment of ship lifetime shortening due to the fatigue yielding under constant and variable amplitude block loadings.

downloadDownload free PDFView PDFchevron_rightAssessment of fatigue capacity in the new bulk carrier and tanker rulesInge Lotsberg

Marine Structures, 2006

During 2004 and 2005 new design rules for bulk carriers and tankers were proposed. The rule proposals were developed in two different projects: The Joint Bulker Project denoted JBP and the Joint Tanker Project denoted JTP. The result from this is that two very different procedures for fatigue assessment of ship structures have been developed. In this paper, the two procedures are reviewed with respect to fatigue capacity. The proposed JBP and JTP analysis procedures have been compared with 200 fatigue test data where the test specimens were subjected to 5 different loading conditions. The procedures are also compared for a typical welded connection subjected to different mean stress levels.

downloadDownload free PDFView PDFchevron_rightDamage mechanics of top-hat stiffeners used in FRP ship constructionWayne Snyder

Marine Structures, 1999

This paper is concerned with the assessment of damage tolerance of a top-hat sti!ener to plate connection in FRP marine structures. The subject is addressed in two parallel schemes, using stress-based and fracture-dependent criteria. Numerical modelling is used to determine the internal load transfer characteristics and failure mechanisms in top-hat sti!eners under typical loadings seen in practice. The "nite element models are benchmarked against published test results, which include phenomena such as delaminations. The models are then extended to include crack elements, which are employed to calculate the strain energy release rates in the form of G values. The result from this modelling is compared against typical experimentally derived data pertaining to G values for the materials in question. Finally, an attempt is made to compare the results of the studies using the two approaches and to judge the overlap.

downloadDownload free PDFView PDFchevron_rightA Preliminary S-N Curve for the Typical Stiffened-Plate Panels of Shipbuilding Structures Preliminarna Krivulja S-N Za Toge Plo(^Ate Panele Za Ladjedelni(Ke StruktureLuljeta Gusha

2007

This paper presents the results of a preliminary study focused on the structural behavior of typical stiffened plate panels used for shipbuilding structures and their fatigue strength under a lateral load. The investigated panels are thin plates, welded with longitudinal bulb stiffeners through alternate welding seams. This makes the panel a composite structural element with a complex strength behavior. The aim of the research was to obtain data about the failure conditions of the panels. Testing covers the bending tests carried out on the real-size panels of shipbuilding structures. A reliable definition of a fatigue design curve was not possible due to the limited number of specimens, although a tentative S-N curve was drawn on the basis of the test data.

downloadDownload free PDFView PDFchevron_rightHitubes Project Design and Integrity Assessment of High Strength Tubular Structures for Extreme Loading Conditions - D3J.-F. Demonceau

2012

downloadDownload free PDFView PDFchevron_rightFatigue Considerations in View of Measured Load SpectraKarl Stambaugh

1982

The SHIP STRUCTURXCOMMITTEEis constituted to prosecutea research programto Improvethe hull structuresof ships and othermarine structures by an extensionof knowledgepertainingto design,materialsand methodsof construction.

downloadDownload free PDFView PDFchevron_rightHAT STIFFENED PLATES FOR SHIP BUILDINGTJPRC Publication

The key interest in ship building is to design a ship having minimum weight and maximum strength. Usage of open sections like Flat bar, Angle bar, Holland Profile and Tee bar are common in ship structure. The stiffeners of closed section offer numerous advantages as much from the structural as from the economic point of view. Hat Stiffened Plate has a number of closed profile stiffeners provided along dominant direction. A representative unit cell of Hat Stiffened Plate has been selected and numerical investigations using finite element software ANSYS have been carried out to quantify the structural advantages of hat shaped stiffeners over the commonly used open section stiffeners like flat bar, angle and tee sections. Hat stiffeners can very effectively be used in the design of lighter ships.

downloadDownload free PDFView PDFchevron_rightStatic and Fatigue Behaviour of the Main Section of a Fast Patrol BoatRaquel Almeida

Procedia Engineering, 2014

This paper analyses the static resistance, as well as the fatigue resistance, of the main section of a fast patrol boat designed and manufactured in Portugal. The ship under study is a high-speed lightweight craft that was mainly fabricated with two types of aluminium series alloys, namely the 5083-H111 and the 6082-T6 alloys, which are commonly used in shipbuilding. The structural response of the critical section of the ship was obtained using the Finite Element Method (FEM), when the structure was submitted to different loading conditions, such as the hydrodynamic and hydrostatic sea loads, the longitudinal sagging or hogging, or the loads on fuel oil tanks. Results obtained for the load cases considered showed that the Von Mises equivalent stresses do not exceed the Yield Strength of the aluminium alloys used in the manufacturing of the ship. In addition, strain gages were placed on the main ship's bulkhead, near a structural detail in its bottom, and real-time acquisition strain data was collected using a computer code routine written in LabView. The Rainflow cycle counting method was applied to load spectrum gathered in order to obtain the Rainflow matrix and to predict the fatigue life of the critical main section of the ship.

downloadDownload free PDFView PDFchevron_rightkeyboard_arrow_downView more papers

• Explore
• Papers
• Topics

• Features
• Mentions
• Analytics
• PDF Packages
• Advanced Search
• Search Alerts

• Journals
• Academia.edu Journals
• My submissions
• Reviewer Hub
• Why publish with us
• Testimonials

• Company
• About
• Careers
• Press
• Help Center
• Terms
• Privacy
• Copyright
• Content Policy

580 California St., Suite 400San Francisco, CA, 94104© 2025 Academia. All rights reserved