Download - GCRC 2019 presentation (2-1)김명현
GCRC-SOP 9th Year International Workshop
Project 2-1
1
Research Background
Overview of Research Contents
Summary of the 2019 research year
Results of Each Research Topic
Validation of the master curve approach based on Charpy impact test with
groove shapes
Fatigue life estimation for HFMI-treated weldments considering weld toe
magnification factors
Strain-based failure assessment based on a reference strain method for
welded pipelines
Research Outcomes (Jan. 2019~Dec. 2019)Project No. 2-1: Reliability and strength assessment of core parts and material system
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Reliability and strength assessment of core parts and material system Acquisition of fatigue and fracture assessment DB (2011.09 ~ 2014.02)
• Fatigue strength assessment for low temperature materials• Investigate for fracture characteristics in offshore structural steels
Development for fatigue fracture analysis method and prediction technology
(2014.03 ~ 2017.02)• Development of advanced fatigue life prediction method• Development for residual stress/welding distortion control technology
Application of advanced design assessment method for offshore
structures (2017.03 ~ 2021.02)• Fitness-for-purpose assessment for ECA(Engineering Critical Assessment)• Development of structural integrity assessment method• To examine application for large welded structures
Project No. 2-1: Reliability and strength assessment of core parts and material system
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The important issues in the design of ship and offshorestructures are fatigue and fracture performances in order tosecure the structural integrity Considering the operating and manufacturing condition of ship and
offshore structure, fatigue and fracture performances are crucial to the structural integrity
Structural integrity assessment of welded structures wherecracks may appear during construction or operation presentsimperative importance
Project No. 2-1: Reliability and strength assessment of core parts and material system
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Validation of the master curve approach based on Charpy impact test with groove shapes• Estimation of master curves with groove shape & sample locations
• Comparison of BS 7910:2013 & BS 7910:2019
Fatigue life estimation for HFMI-treated weldments considering weld toe magnification factors• Welding & HFMI treated Residual Stress Distribution
• Fatigue life estimation for HFMI treated weldments
Strain-based failure assessment based on a reference strain method for welded pipelines• Introduce of strain-based ECA & Reference strain method
• Comparison & Suggestion of Kim and Lee model for J integral estimation against existing model
Project No. 2-1: Reliability and strength assessment of core parts and material system
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Validation of the master curve approach based on Charpy impact testwith groove shapes• Modification of the probability level and/or the reference temperature is required
to include more variety of welding conditions.
Fatigue life estimation for HFMI-treated weldments considering weld toemagnification factors• 𝑴𝒌 value in HFMI treated condition exhibits a significant difference compared to
the As-welded condition.
• Suggested fatigue strength estimation method which consider geometrical effectpresents 90 % higher accuracy compared with without geometrical effect case.
Strain-based failure assessment based on a reference strain method for welded pipelines
• Influence on J-integral values: Under-matching > Over-matching.
• J integral estimation: Proposed method estimates J-integral value better than
other methods.
Project No. 2-1: Reliability and strength assessment of core parts and material system
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Results of Topic 1
7
‘Guide to methods for assessing the acceptability of flaws in metallicstructures’
Supporting a method for evaluating structures on the fracture mechanics
Project No. 2-1: Reliability and strength assessment of core parts and material system
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*SBA: Strain-based assessment
- IIsabel Hadley, Progress towards BS 7910, IIW 2019 (X-1935r-19)
Project No. 2-1: Reliability and strength assessment of core parts and material system
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Engineering critical assessment(ECA) is a effective procedure forevaluating the soundness of structures with flaws and requires reliablefracture toughness data to assess the effect of defects.
Ideal data are typically obtained from samples taken during constructionof an engineering structures or from the structure afterward, but there arein which removal of the test samples is impossible.
Project No. 2-1: Reliability and strength assessment of core parts and material system
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Charpy test Fracture toughness testSpecimen Charpy impact test specimen SE(B) or C(T) specimen
Notch depth 20% of specimen thickness 50% of specimen thickness
Notch type Blunt machine Vee-notch with 0.25mm root radius Fatigue pre-crack
Unit Joules (J) N/mm
<SE(B) specimen><Charpy V-notch test specimen>
Ductile to brittle transition temperature is different by the effects of thedifference between Charpy test and fracture toughness test: specimengeometry, notch depth and notch type.
Project No. 2-1: Reliability and strength assessment of core parts and material system
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BS 7910 provides a method for predicting fracture toughness by theCharpy V-notch impact test.
Availability of Charpy transition curve Calculate 𝑇 through
𝑇 or 𝑇
Yes
No
Estimating fracture toughness by Master Curve
with 𝑇 and 𝐶
Estimatingfracture toughness
by empirical equation with 𝐶
𝐓𝟎: the temperature for median fracture toughness of 100MPa.m0.5 in a 25mm thick fracture toughness specimen𝐓𝟐𝟕𝐉/𝐓𝟒𝟎𝐉: the temperature for 27J/40J measured in a standard Charpy V specimen𝐂𝐯: Charpy V-notch impact energy at the service temperature
Project No. 2-1: Reliability and strength assessment of core parts and material system
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Fracture toughness estimation based on master curve approach
𝐾 20 11 77 exp 0.019 𝑇 𝑇 25/𝐵 . ln 1/ 1 𝑃 .
𝑇 𝑇 18 𝑜𝑟 𝑇 24
𝐓 : Service temperature, ℃
B : Thickness
𝐏𝐟: Probability of 𝐊𝐦𝐚𝐭 being less than estimated. In BS 7910, it is recommended that 𝐏𝐟 𝟎. 𝟎𝟓.
𝐓𝟎: the temperature for median fracture toughness of 100MPa.m0.5 in a 25mm thick fracture toughness specimen.
Reference temperature, 𝑇
• BS 7910:2013 • Revised BS 7910:2019
𝑇 𝑇 87 𝜎1000𝐶𝑉
𝐓𝟐𝟕𝐉/𝐓𝟒𝟎𝐉: the temperature for 27J/40J measured in a standard Charpy V specimen
𝐂𝐕𝐔𝐒: Charpy upper shelf energy
* Pisarski and Bezensek, Estimating fracture toughness from Charpy data, OMAE2019-95787
Master curve approach based on Charpy V-notch impact test
Project No. 2-1: Reliability and strength assessment of core parts and material system
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Prediction equation for 𝑻𝟎 is revised for reasonable estimation of fracture toughness
𝑇 𝑇 → 𝑇 𝑇 87 𝜎1000𝐶𝑉
Reference temperature, 𝑻𝟎
More reasonable
<Predicted fracture toughness by existing method> <Predicted fracture toughness by modified method>
* Pisarski and Bezensek, Estimating fracture toughness from Charpy data, OMAE2019-95787
Project No. 2-1: Reliability and strength assessment of core parts and material system
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Validation of master curve approach with various welding conditions
Test conditions with API 2W Gr.50 and POSTEN 60
Welding type FCAW
Root Face 0 ~ 3mm
Back Gousing O
<Welding conditions>
Over heat input WPS
Current 380 A 320 A
Voltage 40 V 36 V
CPM 20 25
Heat input >45 25 ~ 30
Groove shape X-groove K-groove
Groove angle 60° 45°
<Schematic diagram of welded panel and sample location of mechanical test>
Mechanical tests such as impact, CTOD, and tensile were performed tovalidate the master curve approach based on Charpy impact test data.
Project No. 2-1: Reliability and strength assessment of core parts and material system
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<Charpy transition curve of API 2W Gr.50 and sample location of impact test>
<X-Groove> <K-Groove>
< CTOD transition curve of API 2W Gr.50 and sample location of CTOD test>
<X-Groove> <K-Groove>
Project No. 2-1: Reliability and strength assessment of core parts and material system
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<API 2W Gr. 50 & X-Groove> <API 2W Gr. 50 & K-Groove>
<API 2W Gr. 50 & Over heat input> <API 2W Gr. 50 & WPS>
The difference in sample location and welding conditions are reflected inmaster curves are not consolidated.
Project No. 2-1: Reliability and strength assessment of core parts and material system
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The revised master curve estimates less conservative (higher) fracturetoughness values anticipated from the decreased reference temperature.
More discrepancies at high fracture toughness values.
X-Groove
K-Groove
<Master curve of API 2W Gr. 50 according to BS 7910:2013 and the newly revised BS 7910:2019>
Project No. 2-1: Reliability and strength assessment of core parts and material system
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The largest discrepancy in fracture toughness according to weldingconditions is the groove shape for API 2W Gr. 50 and the heat input forPOSTEN 60.
<API 2W Gr.50 (modified BS7910 & Pf = 0.05)> <POSTEN 60(modified BS7910 & Pf = 0.05)>
Project No. 2-1: Reliability and strength assessment of core parts and material system
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Critical stress intensity factor from CTOD
𝐾𝑚𝜎 𝛿 𝐸
1 𝑣 ,
𝐸 : Elastic modulus
𝜎 : 0.2% proof or yield strength of the material for
which CTOD has been determined
𝛿 : Fracture toughness in terms of CTOD
𝑚 1.517𝜎𝜎
.
𝑓𝑜𝑟 0.3 𝜎 /𝜎 0.98
𝜎 : Tensile strength of the material tested, determined
at the fracture toughness test temperature.
𝜎 𝜎 10
491 1.8𝑇 189
Mechanical properties with assessment temperature
𝜎 𝜎 0.7857 0.2423 exp𝑇
170.646
𝑇 : Assessment temperature
* BS 7910:2013, Guide to methods for assessing the acceptability of flaws in metallic structures. British Standards Institution.
Project No. 2-1: Reliability and strength assessment of core parts and material system
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<X-Groove & Over heat input> <X-Groove & WPS> <K-Groove & WPS>
POSTEN 60
<X-Groove & Over heat input> <X-Groove & WPS> <K-Groove & WPS>
API 2W Gr. 50
Project No. 2-1: Reliability and strength assessment of core parts and material system
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<Fracture toughness of API 2W Gr. 50 & X-groove obtained by Charpy impact energy and CTOD>
In the 0.05 cumulative probability level, both BS7910:2013 and modified2019 tend to overestimate fracture toughness.
Project No. 2-1: Reliability and strength assessment of core parts and material system
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Modification of the probability level and/or the reference temperaturemay be required to include more variety of welding conditions.
Further study for high strength steel, modern welding processes …
𝑇 𝑇 𝟖𝟕 𝜎1000𝐶𝑉 𝑇 𝑇 𝟔𝟓 𝜎
1000𝐶𝑉 𝑃𝑓 𝟎. 𝟎𝟓 𝑃𝑓 𝟎. 𝟎𝟏
<Master curve of API 2W Gr. 50 & X-groove according to reference temperature and probability level>
Project No. 2-1: Reliability and strength assessment of core parts and material system
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Results of Topic 2
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Recent increase in the size of ships and offshore structures lead to higher demands for High strength steel with low plate thickness for the loading capacity.
In case of using high strength steel, steel plate is designed to low thickness, and it causes a fatigue problem.
To guarantee performance of the product, fatigue strength improvement and estimation are conducted frequently.
• Clarkson Research, 2015
Project No. 2-1: Reliability and strength assessment of core parts and material system
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Variety of fatigue improvement methods are suggested.
However, each post treatment is known to be not effective for high strength steel.
Project No. 2-1: Reliability and strength assessment of core parts and material system• Fatigue improvement techniques for welds, J. Johnson, Processbarron
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On the contrary, HFMI treatment exhibits high fatigue improvement performance for the high strength steel.
HFMI treatment effect is attributed by mechanical and geometrical effects.
Mechanical effect of HFMI treatment is properly considered in conventional fatigue estimation methods.
Project No. 2-1: Reliability and strength assessment of core parts and material system
Higher yield strength ‐> Higher fatigue improvement effect
S‐N curve slope As‐ welded : 3HFMI treated : 5
• M. Leitner et al., Fatigue enhancement of thin-walled… , Welding in the world, 2014
27Project No. 2-1: Reliability and strength assessment of core parts and material system
The final goal of this study : an explicit fatigue life method for HFMI treated structure
The research scope Weld toe magnification factor calculation
• I. Stress intensity factor value calculation in HFMI treated weld toe geometry• II. Stress intensity factor value calculation in As-welded weld toe geometry• III. Weld toe magnification factor calculation
Stress Intensity Factor range calculation• I. Residual stress calculation by simulation• II. Stress Intensity Factor range calculation
a. Effective stress ratio calculation (Albrecht & Yamada equation)b. Application of stress ratio model
Fatigue life estimation based on Paris law𝑑𝑎𝑑𝑁 𝐶 𝑀 ∆𝐾
28Project No. 2-1: Reliability and strength assessment of core parts and material system
Paris law𝑑𝑎𝑑𝑁 𝐶 𝑀 ∆𝐾
𝑴𝒌 (Weld toe magnification factor)
𝑀𝐾 𝑜𝑟 𝐾
𝐾
∆𝑲 (Stress intensity factor range)
𝑅𝐾 . 𝐾𝐾 . 𝐾
∆𝐾 1 0.39823𝑅 ∆𝐾
∆𝐾 ∆𝐾
Material Constant
S355 FCGR experiment data
Fatigue life estimation
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Numerical simulation sequence : Welding > Peening (HFMI)
Project No. 2-1: Reliability and strength assessment of core parts and material system
1. Welding- Heat transfer model- Apply the Heat source on the analysis target
2. Residual stress(by welding)- General, Static model- Import the heat-induced stress from heat transfer model to
mechanical stress
3. HFMI treatment- Dynamic, Explicit model- HFMI treatment
30Enter Project No: Project Title in Slide Master
< Result of residual stress simulation >
Redistribution of residual stress : Tensile residual stress (As-welded) -> Compressive residual stress (HFMI treated)
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Stress intensity factor 𝑲 analysis for 𝑴𝒌 calculation : HFMI treated, andAs-welded
Project No. 2-1: Reliability and strength assessment of core parts and material system
< Condition of stress intensity factor analysis>
Crack length / plate thickness [a/t] Load [MPa]
0.01 ~ 0.5 100
As-welded (AW) HFMI
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‘a/t < 0.03’ region : Case 1, 2, and 3 AW
‘a/t > 0.03’ region : Case 1, 2, and 3 AW
Project No. 2-1: Reliability and strength assessment of core parts and material system
HFMI(Case 1,2, and 3)
As -Welded
a/t : 0.03
a/t : 0.03
Slow crack propagation
Slow crack propagation
< Weld magnification factor 𝑴𝒌 >
• [11] K. Ghahremani et al., Quality assurance for high-frequency…, Welding in the world 59, 2015• [12] E. Mikkola et al., A finite element study on residual stress…, International Journal of Fatigue, 2017
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Based on Paris law and material constant of S355, fatigue life of each discrete crack depth 𝑎 is calculated.
Project No. 2-1: Reliability and strength assessment of core parts and material system
< a-N curve comparison between HFMI+𝑴𝒌 and HFMI >
𝑁 𝑑𝑎
𝐶 𝑀 ∆𝐾
Material constant for S355Stress ratio C M
0 2.5893E-15 3.5622
0.25 2.5491E-15 3.7159
0.5 8.2764E-16 3.8907
0.75 4.9643E-14 3.2328
• Abilio M.P de Jesus et al., A comparison of the fatigue behavior…, Journal of Constructional Steel Research, 2012
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Fatigue life estimation result (slope ‘m=5’ corrected) vs Experiment data
Project No. 2-1: Reliability and strength assessment of core parts and material system
• Abilio M.P de Jesus et al., A comparison of the fatigue behavior…, Journal of Constructional Steel Research, 2012
< S355 steel 5mm butt joint S-N curve with fatigue life estimation result (‘m=5’ corrected) >
Load cycle = 10 Exp. HFMI HFMI(RS) HFMI(RS) +
Case 1HFMI(RS) +
Case 2HFMI(RS) +
Case 3Stress range
∆𝜎 [MPa] 240.67 248.38 242.93 237.56 242.42
35
Results of Topic 3
36
Ship & offshore structures which have been damaged locally due to thesevere operating condition may not satisfy its intended design life
In order to determine the maximum allowable flaw sizes at critical weldlocations under operation and extreme environmental load conditionsrequires the ECA
< Flaw initiation at critical weld location > < A schematic failure assessment diagram >
Project No. 2-1: Reliability and strength assessment of core parts and material system
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Most welding fabrication codes specify maximum tolerable flaw sizes
An Engineering Critical Assessment (ECA) is an analysis, based onfracture mechanics principles, of whether or not a given flaw is safe frombrittle fracture, fatigue, creep or plastic collapse under specified loadingconditions
During design, to assist in the choice of welding procedure and/orinspection techniques
During fabrication, to assess the significance of
a) Known defects which are unacceptable to a given fabrication code
b) A failure to meet the toughness requirements of a fabrication code
During operation, to assess flaws found in service and to make decisionsas to whether they can safely remain, or whether down-rating/repair arenecessary
Project No. 2-1: Reliability and strength assessment of core parts and material system
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ECA is carried out by means of a Failure Assessment Diagram (FAD)based on the fracture mechanics.
DNV-OS-F101 => stress-based ECA is generally used with nominal strains< 0.4%
Pipeline in installation and operation => 2~3% strain
< Reeled pipeline >< A schematic stress-based failure assessment diagram >
- DNV-OS-F101, 2013, Submarine Pipeline Systems, Det Norske Veritas, Hovik, Norway
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Cheaitani and He proposed reference strain methods as an alternative tostrain in uncracked condition.
- M Cheaitani and W He, 2011, Strain-based Driving Force Estimates for Circumferential Cracks in Pipe Girth Welds, TWI Ltd
3. Failure assessment diagram
2. J-integral
- J-integral is a main parameter of Option 3 FAD.- FEA is performed to obtain J-integral values.
1. Stress-strain curve
- It is needed to get the option 2 FAD.- Ramberg-Osgood equation
4. Reference strain method
𝐸 𝜺𝒓𝒆𝒇
𝜎𝜎
2𝐸𝜎𝒀 𝜺𝒓𝒆𝒇
𝐽𝐽 Option 2 = 𝜺𝒓𝒆𝒇
𝒀 𝜺𝒓𝒆𝒇
/
Option 3 = 𝜺 𝒓𝒆𝒇
/𝜺
Remote strain
Stre
ss
strain
𝑫𝒓
𝑲𝒓
- Option 2- Option 3
𝑱𝒊𝒏
𝒕𝒆𝒈
𝒓𝒂𝒍
Remote strain
- Elastic J-integral- J-integral
𝜀𝜀
𝜎𝜎 𝛼
𝜎𝜎
Project No. 2-1: Reliability and strength assessment of core parts and material system
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The reference strain & the option 2 equation => more accurate J-integralvalues
The ratio of reference strain and remote strain is independent of remotestrain/applied strain (at strains exceeding 0.5%).
𝜀<0.5%: Reference strain increases linearly.
𝜀>0.5%: Reference strain is a constant value.− M Cheaitani and W He, 2011, Strain-based Driving Force Estimates for Circumferential Cracks in Pipe Girth Welds, TWI Ltd
Reference strain method
𝐸 𝜺𝒓𝒆𝒇
𝜎𝜎
2𝐸𝜎𝒀 𝜺𝒓𝒆𝒇
𝐽𝐽
𝜺 𝒓𝒆𝒇
/𝜺
Remote strain
J‐integral
strain
FEAJ-Integral by Reference strain method by TWIJ-integral by Budden and Ainsworth’s method
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It is essential to consider strength mismatch effects to welded pipeline.
− Guide to methods for assessing the acceptability of flaws in metallic structures (BS 7910), 2013, British Standard Institution
<Homogeneous> <Over−matched structures> <Under−matched structures>
< Classification of plasticity deformation patterns for mismatched structure >
Annex I and P in BS7910 provides the equivalent stress-strain curve for theoption 2 and strength mismatch effects.
𝜎 𝜀
𝐹𝐹 1 𝜎 𝜀 𝑀 𝐹
𝐹 𝜎 𝜀
𝑀 1
∗ 𝑀 𝜀𝜎 𝜀𝜎 𝜀
,𝐹𝐹
𝑓 𝑝𝑖𝑝𝑒 𝑡ℎ𝑖𝑐𝑘𝑛𝑒𝑠𝑠, 𝑐𝑟𝑎𝑐𝑘 𝑑𝑒𝑝𝑡ℎ, 𝑏𝑒𝑎𝑑 𝑤𝑖𝑑𝑡ℎ 𝐴𝑛𝑛𝑒𝑥 𝑃 𝑖𝑛 𝐵𝑆7910
*𝜺𝒑𝒍: plastic strain, W : Weld metal, P : Base metal
Project No. 2-1: Reliability and strength assessment of core parts and material system
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It is essential to consider strength mismatch effects to welded pipeline.
3. Failure assessment diagram
2. J-integral
- J-integral is a main parameter to calculate option 3FAD.
- FEA is performed to obtain J-integral values.
1. Stress-strain curve
4. Reference strain method
𝐸 𝜺𝑴 𝜺𝒑𝒍
𝝈𝑴 𝜺𝒑𝒍
𝜺𝑴 𝜺𝒑𝒍𝟑
2𝐸𝜎𝒀 𝝈𝑴 𝜺𝒑𝒍
𝐽𝐽
𝜎 𝜀
𝐹𝐹 1 𝜎 𝜀 𝑀 𝐹
𝐹 𝜎 𝜀
𝑀 1
𝜀 𝜀𝜎 𝜀
𝐸 𝜀
Option 2 = 𝜺𝒓𝒆𝒇
𝒀 𝜺𝒓𝒆𝒇
/
Option 3 = 𝜺 𝒓𝒆𝒇
/𝜺
Remote strain𝑱
𝒊𝒏𝒕𝒆
𝒈𝒓𝒂
𝒍
Remote strain
- Elastic J-integral- J-integral
𝑫𝒓
𝑲𝒓
- Option 2- Option 3
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Finite element analysis was performed to accomplish the intended goal.
Dimension of the pipe
Outer diameter
[mm]
Length[mm]
Thickness[mm]
Bead width[mm]
400 800 20 5
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Finite element analysis was performed to accomplish the intended goal.
Case 𝜎 of weld metal[MPa]
1 Even-matching 400
2Over-matching
440 (10%)
3 480 (20%)
4Under-matching
360 (10%)
5 320 (20%)
Material PropertiesE
[MPa] 𝛼 𝑛
205800 1 15
• Ramberg‐Osgood equation
𝜺𝜺𝒀
𝝈𝝈𝒀
𝜶𝝈
𝝈𝒀
𝒏
*𝜺𝒀𝝈𝒀𝑬
<Parameters of Ramberg-Osgood equation> <Stress-strain curve of weld metal for mismatch cases>
• BM : 𝜎 400𝑀𝑃𝑎
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Estimated J-integral: Under-matching > Over-matching Reference strain ratio: Under-matching > Even-matching > Over-matching
𝜀 /𝜀 with strength mismatch remains constant at remote strainexceeding 0.5%).
<Reference strain ratio curve><J-integral for each case>
20% UM
10% UM
EM
10% OM
20% OM
20% UM
10% UM
EM
10% OM
20% OM
Strain=0.5% (0.005)
a
b
a > b
a: variation in under-matching caseb: variation in over-matching case
Flat! – independent of remote strain
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Conception
Consideration for
strength mismatc
h
Strain employed
Method AAinsworth and Budden
(strain at flaw location
in uncracked condition)
X Remote strain
Method B O Strain at weld metal obtained by FEA
Method C Cheaitani and He X
Reference strain by Cheaitani and H
e’s
method
Method D Current work OReference strain proposed in this stu
dy
Project No. 2-1: Reliability and strength assessment of core parts and material system
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<J integral estimation through the existing strain method and reference strain method for over-matched pipe>
Existing methods and the proposed method in this study exhibitreasonable correlation of elastic-plastic energy release rates in the caseof overmatching.
In particular, J-integral by Method B and Method D (considering strengthmismatch effects) are close to results from FE analysis.
<10% OM> <20% OM>
Mismatch X
Mismatch O
Mismatch X
Mismatch O
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<20% OM> <20% UM>
<J integral estimation through the existing strain method and reference strain method for over-matched pipe>
Method B (Ainsworth and Budden’s procedure taking into accountstrength mismatch) works fairly well in OM case.
However, Method B excessively over-estimates the J-integral ( by 57%)in UM case.
Thus, Method B is not recommended for undermatching in economicpoint of view.
Method B‐> almost same with FEA resultsin 20% UM
Method B‐> Excessively overshoot in comparison with FEA in 20% UM
Project No. 2-1: Reliability and strength assessment of core parts and material system
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<10% UM> <20% UM>
<J integral estimation through the existing strain method and reference strain method for over-matched pipe>
In 20% under-matching case, Methods A & C with no consideration of themismatch underestimate the J-value by about 13% and 22%, respectively.
It indicates that the actual structure may be subject to more dangerous situationin undermatched case unless mismatch is carefully considered.
The proposed method provides safe and reasonable estimation of J-values
FEA results
Dangerous FEA results
Dangerous
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Publications International Journal (SCI)
Author Paper Journal Vol. No Page Date
Lee D.J., Kim M.K., Walsh J., Jang H.K., Kim H.I., Oh E.Y.,
Nam J.D., Kim M.H., Suhr J.H.
Experimental characterization of temperature dependent dynamic properties of glass fiber
reinforced polyurethane foamsPolymer Testing 74 - 30-38 2019.04
Kim T.Y., Yoon S.W., Cho J.H., Kim M.H.
Vibration characteristics of filament wound composite tubes applied to the intermediate shaft in
ship propulsion systemModern Physics Letters B 33 - - 2019.04
Lee D.J., Shin S.B., Kim M.H.Prediction of traditional behavior of out-of-plane
welding distortion by solar radiation in upper deck of hull structure
Journal of Marine Science and Technology
- - 01-16 2019.05
Kim B.E., Park J.Y., Lee J.S., Lee J.I., Kim M.H.
Effects of the Welding Process and Consumables on the Fracture Behavior of 9 Wt.% Nickel Steel
Experimental Techniques - - 1-12 2019.09
Park J.Y., Kang N.H., Kim M.H.
Effects of the welding processes and consumables on the fatigue and fracture performances for 3.5
wt.% nickel steelsWelding in the world 63 5
1355-1367
2019.09
Park J.H., Kim S.H., Moon H.S., Kim M.H.
Influence of Gravity on Molten Pool behavior and Analysis of Microstructure on Various Welding
Positions in Pulsed Gas Metal Arc WeldingApplied Science 9 21 01-12 2019.10
Project No. 2-1: Reliability and strength assessment of core parts and material system
51
Publications International & Domestic Journal (non-SCI)
International Conference Presentation
저자 논문명 게재지명 권 호 수록면 Date
Park C.H., Kang N.H., Kim M.H., Liu S.
Effect of prestrain on hydrogen diffusion and trapping in structural Material Letters 235 - 193-196 2019.01
박진형, 김성환, 김노원, 문형순, 김명현
A Study in the Bead Shape and Changing Material Properties Depending on the Welding
Position in P-GMAW대한용접․접합학회 - - - 2019.06
이진호, 신용택, 김명현 용접홈형상에따른샤르피충격시험기반마스터선도접근법의검증에관한연구
대한용접․접합학회 37 6 539-546 2019.12
Project No. 2-1: Reliability and strength assessment of core parts and material system
Author Conference Title Nation
InternationalConference
Conference
Lee J.S., Kim M.H. OMAEInvestigation of Strain-Based Failure Assessment
Based on Reference Strain Method for Welded Pipes영국
Kim D.Y., Kim M.H. OMAEFatigue Life Estimation for HFMI Treated Weldments
Considering Weld Toe Magnification Factor영국
Park J.Y., Kim M.H. IIWInvestigation of fatigue and fracture characteristic for
low temperature metals considering the effect of various alloying components
슬로바키아
Kim M.H.2019 East Welding
and Joining Conference
Investigation of strain-based failure assessment based on reference strain method for welded
pipelines대한민국
52
Publications Conference Presentation
Author Conference Title Nation
Domestic Conference
Conference
박정열, 김명현
대한용접ㆍ접합학
회
클립게이지를이용한 CTOD 측정방법에과한비교
연구
한국
이재성, 김명현과대하중을고려한고망간강용접부의
피로균열전파특성에대한연구
박정열, 김명현A study on crack tip opening displacement for high
manganese steel considering welding process
문동현, 김명현Constraint-based Fracture Assessment for Welded
Joint
김동엽, 김명현필렛용접부에대한 High Frequency Mechanical
Impact treatment 시뮬레이션을위한파라메트릭연구
김동엽, 김명현A fatigue life estimation of butt welded joints
considering HFMI weld toe magnification factor
이진호, 김명현원주용접파이프의반복응력-변형률선도를고려한
구조변형률방법기반저주기피로평가Ⅱ
최명환, 이정훈, 남형빈, 김명현, 조대원, 강남현
극저온용고망간강용접부의인장및미세조직거동
김명현 대한조선학회
선박해양플랜트
구조연구회
Introduction to the revised BS7910 (2019)
김동엽, 김명현 Fatigue assessment of HFMI treated welded joints
이진호, 김명현 Low cycle fatigue based on strain based approach
Project No. 2-1: Reliability and strength assessment of core parts and material system
53
Publications Conference Presentation
Education MS Graduate
• 3 graduated Ph. D. Graduate
• 2 graduated
Project No. 2-1: Reliability and strength assessment of core parts and material system
Author Conference Title Nation
Domestic Conference
Conference
김동엽, 김명현
대한용접ㆍ접합학
회
HFMI Weld Toe Magnification Factor를고려한
맞대기용접부피로수명추정연구 PART 2
한국
이진호, 김명현다양한용접조건을고려한샤르피충격시험기반
마스터선도접근법에대한연구
박정열, 김명현7 wt.% 니켈강파괴인성기반용접부의 Master curve
평가에관한연구
이진호. 김명현원주용접파이프의구조변형률기반저주기피로
저평가에대한연구
54
Industry-University Liaison Research Grant
• 해양 Tubular 용접부의자동 ECA 프로그램개발
(2017.12 ~ 2019.03, (주)현대중공업• 초대형컨테이너선용 EH51BCA강용접이음부피로시험 DATA 확보
(2018.05 ~ 2019.02, (주)포스코)• 에틸렌운반선용 5% Ni강용접이음부피로성능확보기술개발
(2018.11 ~ 2020.01, (주)포스코)• Mark-Flex Aramid FSB 극저온피로강도평가Ⅱ
(2019.03 ~ 2019.08, (주)한국카본)• LNG CCS용멤브레인피로성능평가Ⅱ
(2019.03 ~ 2019.08, (주)동성화인텍)• 카본 SMC 피로시험및피로수명예측방법도출
(2019.07 ~ 2020.07, 현대자동차(주))• 피로성능향상기법에따른맞대기용접부피로강도평가
(2019.08 ~ 2019.11, 현대로템(주))
Project No. 2-1: Reliability and strength assessment of core parts and material system
55
Industry-University Liaison Research Grant
• 이중구조를갖는 IMO 타입 B 탱크용스프레이형단열시스템평가
(2019.09 ~ 2019.11, (주)GASPACK• SUS304L 소재의소성변형및압연방향을고려한인장시험평가
(2019.11 ~ 2019.12, 대우조선해양(주))• 연안선박용중소형 LNG 연료저장모듈개발
(2019.11 ~ 2019.12, 중소조선연구원)• MLNGC CCS 2차방법피로시험
(2019.11 ~ 2020.10, 한국조선해양(주))• 러더트렁크구조용접변형에대한간이수치평가
(2019.12 ~ 2020.01, (주)코피코)
Intellectual Properties Registered
• 해양 Tubular Joint 용접부에대한자동구조건전성평가프로그램
Project No. 2-1: Reliability and strength assessment of core parts and material system
56