A path-dependent cycle counting method for variable-amplitude multi-axial loading

Dong, Ping; Wei, Zhigang; Hong, J. K.

doi:10.1016/j.ijfatigue.2009.10.010

Cited by 93 publications

(84 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although local (notch) information is involved, the loading & response conditions are far field (fracture plane) defined meaning multiaxiality is limited to mixed mode-I and mode-III cases and hot spot structural stress criterion developments like multi-axial cycle counting in the Von Mises plane (e.g. Dong et al 2010;Wei and Dong 2011;Mei and Dong 2016) can be applied. However, endurance is incorporated only and counting in the S B −T B rather than σ s −τ s plane has been proposed (Hong and Forte 2014), involving the mechanism (i.e.…”

Section: Battelle Structural Stress Criterionmentioning

confidence: 99%

Fatigue damage criteria classification, modelling developments and trends for welded joints in marine structures

Besten

2018

Ships and Offshore Structures

View full text Add to dashboard Cite

Fatigue is typically a governing limit state for marine structures. Welded joints are the weakest links in that respect. Physics involve several resistance dimensions, a range of scales and distinct contributions in different stages of the accumulative damage process. Fatigue damage criteria developed over time have been classified with respect to type of information, geometry, parameter and process zone including plane and life region annotations. The criteria are evaluated regarding model (in)capabilities, showing up to what extent (governing) physics are taken into account. Modelling developments and trends towards complete strength, multi-scale and total life criteria have been identified. Incorporating all four (interacting) fatigue resistance dimensions: material, geometry, loading & response and environment translates into a complete strength fatigue damage criterion. Considering macro-, meso-and micro-scale information provides a multi-scale fatigue damage criterion. Correlation of crack initiation and growth requires matching intact and cracked geometry parameters, revealing a total life fatigue damage criterion. HIGHLIGHTS• Classification of fatigue damage criteria with respect to type of information, geometry, parameter and process zone including plane and life region annotations.• Identification of modelling developments and trends towards complete strength, multi-scale and total life fatigue damage criteria for welded joints in marine structures. NomenclatureA notch strain energy density process zone area C crack growth or fatigue resistance curve intercept (endurance coefficient) D fatigue damage E normal strain at macro-scale E Young's modulus J crack tip energy density J 1 hydrostatic stress or strain component J 2 deviatoric stress or strain component K σ crack tip stress intensity factor K ɛ crack tip strain intensity factor K' work hardening coefficient K N notch stress intensity factor K N I mode-I notch stress intensity factor K N III mode-III notch stress intensity factor K I mode-I stress intensity factor K I T total mode-I stress intensity factor K I r residual mode-I stress intensity factor K III mode-III stress intensity factor K * FE dimensionless FE based notch stress intensity factor N (total) number of cycles until failure N i number of cycles corresponding to initiation N g number of cycles corresponding to growth R notch strain energy density process zone radius S stress based fatigue damage criterion S B Battelle structural normal stress range S e effective notch stress range S eq (equivalent) Von Mises stress range S n nominal stress range S s hot spot structural stress range S T total stress range T temperature T B Battelle structural shear stress range T σS strength scatter band index W energy based fatigue damage criterion W N notch strain energy W N A notch strain energy density Y n notch factor Y f far field factor a crack size (i.e. length) a 0 critical defect size a d long-term corrosion pit size (i.e. depth) a i (real) defect or initial crack size a n (root) not...

show abstract

Section: Battelle Structural Stress Criterionmentioning

confidence: 99%

Fatigue damage criteria classification, modelling developments and trends for welded joints in marine structures

Besten

2018

Ships and Offshore Structures

View full text Add to dashboard Cite

show abstract

“…However, difficulties start to arise when it is intended to execute a multiaxial fatigue analysis on a structure under OP VA loading, which is representative for the actual day-to-day loading on marine structures. For this purpose a case study was developed by the authors and was then used to investigate the effect of stress amplitude ratio on fatigue damage using PDMR based multiaxial cycle counting [52]. Marine structures are in reality subjected to a combination of stationary sea states whereby each sea state consists of one, two or several wave systems [53].…”

Section: Variable Amplitude Loading -Case Studymentioning

confidence: 99%

“…The authors used their own multiaxial cycle counting algorithm developed based on publications of the PDMR cycle counting method [52,57,58]. This algorithm was used to process time traces of normal and shear nominal stress which were generated with the two considered wave spectra.…”

Section: Fatigue Lifetime Estimationmentioning

confidence: 99%

Comparative study of multiaxial fatigue methods applied to welded joints in marine structures

Lieshout¹,

Besten²,

Kaminski³

2016

Frattura Ed Integrità Strutturale

View full text Add to dashboard Cite

ABSTRACT. Marine structures are particularly prone to action of waves, winds and currents with stochastically varying composition, intensities and directions. Therefore, resultant stresses may cause multiaxial fatigue in specific welded structural details. For the assessment of multiaxial fatigue in welded joints, a wide variety of methods have been suggested. However, there is still no consensus on a method which can correctly account for non-proportional and variable amplitude loading. This paper beholds a comparative study of multiaxial fatigue methods applicable for design of marine structures. For the purpose of comparison several load cases were defined including non-proportional and variable amplitude loadings with different normal and shear stress amplitude ratios. Three types of methods are compared: those described by three different codes (i.e. Eurocode 3, IIW and DNV-GL), those described by three different multiaxial fatigue approaches from literature (i.e. Modified Carpinteri-Spagnoli Criterion, Modified Wohler Curve Method and Effective Equivalent Stress Hypothesis) and an approach based on Path-Dependent-Maximum-Range multiaxial cycle counting. From this study it has been concluded that non-proportional variable amplitude loading has a significant negative impact on the fatigue lifetime estimates, and that further research and experimental testing are essential to come to a consensus.

show abstract

“…Various models have been introduced in the literature for performing multi‐axial fatigue analysis and most of them are limited to proportional or simple non‐proportional loadings 6 . Recently, a path‐length based multi‐axial cycle counting and fatigue life assessment procedure has been proposed 7, 8 . This method avoids the concepts ‘peak' and ‘valley' as used in traditional rainflow counting but instead works with the concept ‘distance'.…”

Section: Introductionmentioning

confidence: 99%

“…The S − N curve is usually obtained by curve fitting tested data using least square or maximum likelihood method, and it has been standardized for industry application, such as ASTM 10 . Recently, the standard practice, as adopted by ASTM and many other standards, for statistical analysis of linear or linearized stress‐life and strain‐life fatigue data has been critically reviewed and its limitation can be overcome by using a newly developed approach; 11 , 12 The effectiveness of the path‐length dependent multi‐axial cycle counting method 7,8 has been validated by its ability to correlate multi‐axial fatigue data available in the literature and it provides a reliable way to address items (2) and (3) above; Miner's linear damage rule, 3 that is, a component fails when the accumulated damage equals unity or other certain values, based on experimental data, is often well accepted and has been adopted in many engineering applications.…”

Section: Introductionmentioning

confidence: 99%

A rapid path‐length searching procedure for multi‐axial fatigue cycle counting

Wei

Dong

2012

Fatigue Fract Eng Mat Struct

View full text Add to dashboard Cite

In this paper, a series of advanced searching algorithms have been examined and implemented for accelerating multi‐axial fatigue cycle counting efforts when dealing with large time histories. In a computerized calculation of the path‐length dependent cycle counting method, most of the central processor unit's (CPU) time is spent on searching for the maximum range or distance in a stress or strain space. A brute‐force search is the simplest to implement, and will always find a solution if it exists. However, its cost, in many practical problems, tends to grow exponentially as the size of the loading spectrum increases with a search time measured in the order of O(n2), where n is the number of spectrum data points. In contrast, a form of Andrew's monotone chain algorithm, as demonstrated in this paper, can remarkably reduce the solution time to the order of O(n log n). The effectiveness of the new path‐length searching procedure is demonstrated by a series of worked examples with a varying degree of non‐proportionality in multi‐axial loading history.

show abstract

A path-dependent cycle counting method for variable-amplitude multi-axial loading

Cited by 93 publications

References 23 publications

Fatigue damage criteria classification, modelling developments and trends for welded joints in marine structures

Fatigue damage criteria classification, modelling developments and trends for welded joints in marine structures

Comparative study of multiaxial fatigue methods applied to welded joints in marine structures

A rapid path‐length searching procedure for multi‐axial fatigue cycle counting

Contact Info

Product

Resources

About