Offshore structures are exposed to severe operating conditions because energy resource development has recently extended toward deeper seabed and lower temperature regions. Hence, fracture toughness evaluation for very thick and high strength steels is one of the most important parameters required for the structural integrity assessment of offshore structures. Fracture toughness is known as a property which describes the ability of a material containing a crack to resist unstable brittle fracture. Crack tip opening displacement (CTOD) and J integral are the most commonly employed parameters as fracture criteria in elastic plastic fracture mechanics (EPFM). There have been extensive research efforts to clarify the relationship between CTOD and J integral in elastic plastic regime. Plastic constraint factor (PCF) in the relationship between CTOD and J integral can serve as a parameter to characterize constraint effects in fracture involving plastic deformation. In this regard, the characteristics of the PCF are of significant importance in EPFM analysis. In this study, we evaluated fracture toughness of American Petroleum Institute (API) 2 W Gr. 50 steel in terms of CTOD in various temperatures using single edge notched bend (SENB) specimens. Test specimens are fabricated by submerged arc welding (SAW) and flux cored arc welding (FCAW). In addition, CTOD values are compared to absorbed impact energy with respect to the weld metal (WM) and heat affected zone (HAZ). Then, we investigated PCFs with respect to several regions of the weldment at various temperatures. Experimental values of PCFs were calculated and then compared against the predicted values according to the American Society for Testing and Materials (ASTM) standard. CTOD values of WM by SAW is found to be about three times higher than that of FCAW at −10 °C, and CTOD values calculated by the ASTM standard are approximately 30% lower than the CTOD according to British Standard (BS). In addition, the maximum of 40% discrepancy is observed in PCFs obtained between the experiment and the predicted values according to the ASTM standard. This may lead to too conservative fracture toughness estimation for the welded joints of API 2 W Gr. 50 steel when using PCF by ASTM. Based on the accurate estimated PCF values obtained from this study, it is believed that rational fracture design of offshore structures is possible.
Skip Nav Destination
Article navigation
December 2015
Technology Review
Estimation of Constraint Factor on the Relationship Between J Integral and CTOD for Offshore Structural Steel Weldments
Dong-Hyun Moon,
Dong-Hyun Moon
Department of Naval Architecture and Ocean Engineering,
Pusan National University,
Busan 609-735, South Korea
e-mail: dhyun@pusan.ac.kr
Pusan National University,
Busan 609-735, South Korea
e-mail: dhyun@pusan.ac.kr
Search for other works by this author on:
Deok-Geun Kim,
Deok-Geun Kim
Department of Naval Architecture and Ocean Engineering,
Pusan National University,
Busan 609-735, South Korea
e-mail: dgkim@pusan.ac.kr
Pusan National University,
Busan 609-735, South Korea
e-mail: dgkim@pusan.ac.kr
Search for other works by this author on:
Jeong-Soo Lee,
Jeong-Soo Lee
Technology Research Institute,
Total Marine Service Co., Ltd.,
Busan 600-814, South Korea
e-mail: leejs@tms2010.com
Total Marine Service Co., Ltd.,
Busan 600-814, South Korea
e-mail: leejs@tms2010.com
Search for other works by this author on:
Jae-Myung Lee,
Jae-Myung Lee
Department of Naval Architecture and Ocean Engineering,
Pusan National University,
Busan 609-735, South Korea
e-mail: jaemlee@pusan.ac.kr
Pusan National University,
Busan 609-735, South Korea
e-mail: jaemlee@pusan.ac.kr
Search for other works by this author on:
Myung-Hyun Kim
Myung-Hyun Kim
Department of Naval Architecture and Ocean Engineering,
Pusan National University,
Busan 609-735, South Korea
e-mail: kimm@pusan.ac.kr
Pusan National University,
Busan 609-735, South Korea
e-mail: kimm@pusan.ac.kr
Search for other works by this author on:
Dong-Hyun Moon
Department of Naval Architecture and Ocean Engineering,
Pusan National University,
Busan 609-735, South Korea
e-mail: dhyun@pusan.ac.kr
Pusan National University,
Busan 609-735, South Korea
e-mail: dhyun@pusan.ac.kr
Deok-Geun Kim
Department of Naval Architecture and Ocean Engineering,
Pusan National University,
Busan 609-735, South Korea
e-mail: dgkim@pusan.ac.kr
Pusan National University,
Busan 609-735, South Korea
e-mail: dgkim@pusan.ac.kr
Jeong-Soo Lee
Technology Research Institute,
Total Marine Service Co., Ltd.,
Busan 600-814, South Korea
e-mail: leejs@tms2010.com
Total Marine Service Co., Ltd.,
Busan 600-814, South Korea
e-mail: leejs@tms2010.com
Jae-Myung Lee
Department of Naval Architecture and Ocean Engineering,
Pusan National University,
Busan 609-735, South Korea
e-mail: jaemlee@pusan.ac.kr
Pusan National University,
Busan 609-735, South Korea
e-mail: jaemlee@pusan.ac.kr
Myung-Hyun Kim
Department of Naval Architecture and Ocean Engineering,
Pusan National University,
Busan 609-735, South Korea
e-mail: kimm@pusan.ac.kr
Pusan National University,
Busan 609-735, South Korea
e-mail: kimm@pusan.ac.kr
1Corresponding author.
Contributed by the Ocean, Offshore, and Arctic Engineering Division of ASME for publication in the JOURNAL OF OFFSHORE MECHANICS AND ARCTIC ENGINEERING. Manuscript received June 17, 2013; final manuscript received September 3, 2015; published online October 15, 2015. Assoc. Editor: Lance Manuel.
J. Offshore Mech. Arct. Eng. Dec 2015, 137(6): 064001 (6 pages)
Published Online: October 15, 2015
Article history
Received:
June 17, 2013
Revised:
September 3, 2015
Citation
Moon, D., Kim, D., Lee, J., Lee, J., and Kim, M. (October 15, 2015). "Estimation of Constraint Factor on the Relationship Between J Integral and CTOD for Offshore Structural Steel Weldments." ASME. J. Offshore Mech. Arct. Eng. December 2015; 137(6): 064001. https://doi.org/10.1115/1.4031668
Download citation file:
Get Email Alerts
Cited By
Numerical Analysis of the Effect of Tunnel Hydrofoil—Stern Flap on the Motion Stability of a Double M-Craft in Regular Waves
J. Offshore Mech. Arct. Eng (August 2025)
On the Performance of a Data-Driven Backward Compatible Physics-Informed Neural Network for Prediction of Flow Past a Cylinder
J. Offshore Mech. Arct. Eng (August 2025)
Full-Scale Testing of Corrosion Resistant Alloy-Mechanically Lined Pipes for Submarine Pipelines
J. Offshore Mech. Arct. Eng
An Improved Direct Forcing Immersed Boundary Method With Integrated Mooring Algorithm for Floating Offshore Wind Turbines
J. Offshore Mech. Arct. Eng (August 2025)
Related Articles
Investigation of the Beltline Welding Seam and Base Metal of the Greifswald WWER-440 Unit 1 Reactor Pressure Vessel
J. Eng. Gas Turbines Power (May,2011)
Heat-Affected Zone Fracture Toughness of 420–500-MPa Yield Strength Steels: Effects of Chemical Composition and Welding Conditions
J. Offshore Mech. Arct. Eng (February,1993)
Crack Arrest Toughness of a Heat-Affected Zone Containing Local
Brittle Zones
J. Offshore Mech. Arct. Eng (November,1996)
A New High-Yield-Strength Alloy Steel for Welded Structures
Trans. ASME (April,1952)
Related Proceedings Papers
Related Chapters
A 3D Cohesive Modelling Approach for Hydrogen Embrittlement in Welded Joints of X70 Pipeline Steel
International Hydrogen Conference (IHC 2012): Hydrogen-Materials Interactions
Subsection NE—Class MC Components
Companion Guide to the ASME Boiler & Pressure Vessel Codes, Volume 1 Sixth Edition
Subsection NE — Class MC Components
Companion Guide to the ASME Boiler and Pressure Vessel Code, Volume 1, Third Edition