Numerical Investigation of the Capacity of Anchor Chain Links in Clay
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 150, Issue 10
Abstract
Offshore floating systems are held in position with chains that connect the floater to anchors embedded in the seabed. An essential component for calculating the overall mooring capacity is an accurate assessment of the holding resistance from the anchor chains. Existing studies generally simplify the (complex) chain geometry to that of a cylindrical bar, which does not account for the intricate geometry of the connected chain links. This paper reports on three-dimensional finite-element modeling that defined the capacity of a link of anchor chain in clay soil with consideration of the geometry of the chain links, including the influence from adjacent links. Both stud link and studless links were considered, along with the effect of embedment depth, link direction angle, and interface condition. The soil resistance acting on the chain links, represented by uniaxial bearing capacity factors , , and along the normal, lateral, and axial directions of the chain link, respectively, were derived, and the soil failure mechanisms for these conditions are discussed. Equivalent bearing capacity factors and were derived by converting the soil resistance to normal and tangential resistances ( and ) acting on an equivalent cylindrical bar. Ultimately, was calculated to represent the friction coefficient, , which ranged from 0.2 to 0.4.
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Data Availability Statement
Some or all data, models or code that support the findings of this study are available from the corresponding author upon reasonable request.
Acknowledgments
This research was undertaken with support from the Australian Research Council (ARC) Discovery Projects (DP180103314 and DP190103315) and the ARC Industrial Transformation Research Hub for Offshore Floating Facilities, which is funded by the Australian Research Council, Woodside Energy, Shell, Bureau Veritas, and Lloyds Register (Grant No. IH140100012). The corresponding author’s ARC Future Fellowship (FT200100457) is acknowledged. Phil Watson leads the Shell Chair in Offshore Engineering research team at The University of Western Australia, which is sponsored by Shell Australia. Professor Fraser Bransby at The University of Western Australia is appreciated for his discussions, suggestions, and review of this study.
References
ABS (American Bureau of Shipping). 2017. Design and installation of drag anchors and plate anchors. Houston: American Bureau of Shipping.
Aubeny, C., and C. M. Chi. 2014. “Analytical model for vertically loaded anchor performance.” J. Geotech. Geoenviron. Eng. 140 (1): 14–24. https://doi.org/10.1061/(ASCE)GT.1943-5606.0000979.
Dassault Systèmes. 2019. SIMULIA user assistance 2019: Abaqus. Providence, RI: Dassault Systèmes Simulia Corp.
Degenkamp, G., and A. Dutta. 1989. “Soil resistances to embedded anchor chain in soft clay.” J. Geotech. Eng. 115 (10): 1420–1438. https://doi.org/10.1061/(ASCE)0733-9410(1989)115:10(1420).
DNV GL. 2017. Design and installation of plate anchors in clay. DNVGL-RP-E302. Høvik, Norway: Det Norske Veritas.
Frankenmolen, S. F., D. J. White, and C. D. O’Loughlin. 2016. “Chain-soil interaction in carbonate sand.” In Proc., Annual Offshore Technology Conf. Houston: Offshore Technology Conference. https://doi.org/10.4043/27102-MS.
Han, C., and J. Liu. 2017. “A modified method to estimate chain inverse catenary profile in clay based on chain equation and chain yield envelope.” Appl. Ocean Res. 68 (Oct): 142–153. https://doi.org/10.1016/j.apor.2017.08.016.
Liu, W., Y. Tian, and M. J. Cassidy. 2021. “An interface to numerically model undrained soil-structure interactions.” Comput. Geotech. 138 (Oct): 104327. https://doi.org/10.1016/j.compgeo.2021.104327.
Liu, W., Y. Tian, M. J. Cassidy, and P. Watson. 2024. “A new analytical approach to model embedded anchor lines based on the yield surface of soil resistance.” Géotechnique.
Merifield, R. S., A. V. Lyamin, S. W. Sloan, and H. S. Yu. 2003. “Three-dimensional lower bound solutions for stability of plate anchors in clay.” J. Geotech. Geoenviron. Eng. 129 (3): 243–253. https://doi.org/10.1061/(ASCE)1090-0241(2003)129:3(243).
Neubecker, S. R., and M. F. Randolph. 1995. “Profile and frictional capacity of embedded anchor chains.” J. Geotech. Eng. 121 (11): 797–803. https://doi.org/10.1061/(ASCE)0733-9410(1995)121:11(797).
O’Loughlin, C. D., D. J. White, and S. A. Stanier. 2017. “Plate anchors for mooring floating facilities—A view towards unlocking cost and risk benefits.” In Vol. 2 of Proc., 8th Int. Conf. on Offshore Site Investigation and Geotechnics, 978–986. London: Society for Underwater Technology.
O’Neill, M. P., M. F. Bransby, and M. F. Randolph. 2003. “Drag anchor fluke–soil interaction in clays.” Can. Geotech. J. 40 (1): 78–94. https://doi.org/10.1139/t02-096.
Rocha, M. M., F. Schnaid, C. C. M. Rocha, and C. S. Amaral. 2016. “Inverse catenary load attenuation along embedded ground chain of mooring lines.” Ocean Eng. 122 (Aug): 215–226. https://doi.org/10.1016/j.oceaneng.2016.06.027.
Skempton, A. W. 1951. The bearing capacity of clays, 180–189. London: Building Research Congress.
Song, Z., Y. Hu, and M. F. Randolph. 2008. “Numerical simulation of vertical pullout of plate anchors embedded in clay.” J. Geotech. Geoenviron. Eng. 134 (6): 866–875. https://doi.org/10.1061/(ASCE)1090-0241(2008)134:6(866).
Supachawarote, C., M. Randolph, and S. Gourvenec. 2004. “Inclined pull-out capacity of suction caissons.” In Proc., 14th Int. Offshore and Polar Engineering Conf., 500–506. Toulon, France: International Society of Offshore and Polar Engineers.
Tian, Y., M. F. Randolph, and M. J. Cassidy. 2015. “Analytical solution for ultimate embedment depth and potential holding capacity of plate anchors.” Géotechnique 65 (6): 517–530. https://doi.org/10.1680/geot.14.P.228.
Vivatrat, V., P. J. Valent, and A. A. Ponterio. 1982. “The influence of chain friction on anchor pile design.” In Proc., 14th Annual Offshore Technology Conf., 153–163. Houston: Offshore Technology Conference. https://doi.org/10.4043/4178-MS.
Vryhof Anchors. 2015. Anchor manual 2015: The guide to anchoring. Schiedam, Netherlands: Vryhof Anchors.
Wang, D., Y. Hu, and M. F. Randolph. 2010a. “Three-dimensional large deformation finite-element analysis of plate anchors in uniform clay.” J. Geotech. Geoenviron. Eng. 136 (2): 355–365. https://doi.org/10.1061/(ASCE)GT.1943-5606.0000210.
Wang, L. Z., Z. Guo, and F. Yuan. 2010b. “Quasi-static three-dimensional analysis of suction anchor mooring system.” Ocean Eng. 37 (13): 1127–1138. https://doi.org/10.1016/j.oceaneng.2010.05.002.
Yang, M., J. D. Murff, and C. P. Aubeny. 2010. “Undrained capacity of plate anchors under general loading.” J. Geotech. Geoenviron. Eng. 136 (10): 1383–1393. https://doi.org/10.1061/(ASCE)GT.1943-5606.0000343.
Yen, B. C., and G. D. Tofani. 1984. “Soil resistance to stud link chain.” In Proc., 16th Annual Offshore Technology Conf., 479–488. Houston: Offshore Technology Conference. https://doi.org/10.4043/4769-MS.
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© 2024 American Society of Civil Engineers.
History
Received: Feb 11, 2023
Accepted: Apr 18, 2024
Published online: Jul 27, 2024
Published in print: Oct 1, 2024
Discussion open until: Dec 27, 2024
ASCE Technical Topics:
- Analysis (by type)
- Anchors
- Clays
- Design (by type)
- Engineering fundamentals
- Equipment and machinery
- Finite element method
- Foundation design
- Foundations
- Geomechanics
- Geometrics
- Geotechnical engineering
- Highway and road design
- Highway engineering
- Highway transportation
- Infrastructure
- Load and resistance factor design
- Load bearing capacity
- Load factors
- Methodology (by type)
- Numerical analysis
- Numerical methods
- Soil mechanics
- Soils (by type)
- Structural design
- Structural engineering
- Structural reliability
- Transportation engineering
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