Definition
Drag anchors, which are evolved from conventional ship anchors, are usually penetrated into seabed by drag vessels to transmit an applied tensile load mainly through the fluke to a load bearing stratum.
Scientific Fundamentals
Types of Drag Anchors
Drag anchor is an important component of mooring system in deep water applications. It mainly consists of a broad fluke (providing main resistance, Fig. 1) and a shank (connecting the fluke to the mooring line, Fig. 2). Traditionally, the angle between them is fixed with a potential adjustment before penetration to the seabed but various in different soils, 50° for clay and 30° for sand, etc. (Randolph and Gourvenec 2011). The capacity of the drag anchor is mobilized primarily by the bearing resistance and side resistance on the anchor fluke and the friction along the embedded portion of mooring lines (Fig. 2), usually it can develop a...
References
API, RP2SK (2005) Design and analysis of station keeping systems for floating structures. American Petroleum Institute
DNV (2017) Design and installation of fluke anchors in clay. Recommended practice DNV-RP-E301
Gao FP, Li JH, Qi WG, Hu C (2015) On the instability of offshore foundations: theory and mechanism. Physics, Mechanics & Astronomy 58(12):124701-01-15
Kim BM (2005) Upper bound analysis for drag anchors in soft clay. Doctoral dissertation, A&M University
Liu HX, Zhang W, Liu CL, Hu C (2012) Movement direction of drag anchors in seabed soils. Appl Ocean Res 34(2012):78–95
Merifield RS, Sloan SW, Yu HS (2001) Stability of plate anchors in undrained clay. Geotechnique 51(2):141–153
Murff JD, Anderson H (2001) Deepwater anchor design practice-first year report to API. Offshore Technology Research Center, Texas A&M University, College Station
Neubecker SR, Randolph MF (1996) The performance of drag anchor and chain systems in cohesive soil. Marine georesources & geotechnology 14(2):77–96
O’Neill MP, Neubecker SR, Erbrich CT (2011) Installation and in-place assessment of drag anchors in carbonate soil. In: Frontiers in offshore Geotechnics II. Taylor & Francis Group, London, pp 747–752
Randolph M, Gourvenec S (2011) Offshore geotechnical engineering. Taylor & Francis, London
Thompson D, Beasley DJ, True DG, Lin ST, Briaud JL, Seelig WN, Jung B (2012) Handbook for marine geotechnical engineering (No. NFESC-SP-2209-OCN). Naval Facilities Engineering Command Port Hueneme CA Engineering Service Center
Vryhof Anchors (2015) Anchor manual 2015–the guide to anchoring. Global Maritime, Vryhof Anchors
Wu XN (2017) Numerical modelling of behavior of drag anchors. PhD thesis, National University of Singapore
Zhang W (2011) Penetration mechanism and kinematic behavior of drag anchor. PhD thesis, Tianjin University
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Section Editor information
Rights and permissions
Copyright information
© 2021 Springer Nature Singapore Pte Ltd.
About this entry
Cite this entry
Hu, C. (2021). Drag Anchors. In: Cui, W., Fu, S., Hu, Z. (eds) Encyclopedia of Ocean Engineering. Springer, Singapore. https://doi.org/10.1007/978-981-10-6963-5_208-1
Download citation
DOI: https://doi.org/10.1007/978-981-10-6963-5_208-1
Received:
Accepted:
Published:
Publisher Name: Springer, Singapore
Print ISBN: 978-981-10-6963-5
Online ISBN: 978-981-10-6963-5
eBook Packages: Springer Reference EngineeringReference Module Computer Science and Engineering