Abstract

As the latest development of gravity installed anchors (GIAs), the OMNI-Max anchor has drawn much attention from worldwide due to its unique behavior in the seabed. The pullout capacity of OMNI-Max anchors is a key index in engineering. However, most of the relevant studies were carried out under a quasi-static condition, which do not actually meet the installation and operation requirements. In practice, the anchor may be subjected to both long-term and short-term sharp loading during mooring. As an important environmental variable, it is essential to evaluate the effect of loading rate on the pullout capacity. Since the bearing capacity of OMNI-Max anchors is affected by many factors, it is also essential to explore systematically the coupling effects of the loading rate and other factors, including the anchor embedment depth, the anchor orientation, the bearing area, the loading angle, and the soil strength. Based on the coupled Eulerian–Lagrangian (CEL) technique, numerous analytical cases are designed and calculated by the large deformation finite element (LDFE) method. The loading rates span four orders of magnitude from the quasi-static velocity to 10 m/s (about one anchor length per second), covering a wider range in pulling out of GIAs. The end-bearing capacity factor changes remarkably with the pullout velocity for OMNI-Max anchors, and the increase can even reach more than twice of that in a quasi-static condition. As a result, a succinct explicit expression is constructed in terms of the loading rate and multiple factors, which can be effectively utilized to calculate the end-bearing capacity factor of OMNI-Max anchors in clay under complex conditions.

References

1.
Zimmerman
,
E. H.
,
Smith
,
M. W.
, and
Shelton
,
J. T.
,
2009
, “
Efficient Gravity Installed Anchor for Deep Water Mooring
,”
41st Offshore Technology Conference (OTC)
,
Houston, TX
,
May 4–7
, SPE Paper No. OTC-20117-MS.
2.
Shelton
,
J. T.
,
2007
, “
OMNI-Max Anchor Development and Technology
,”
OCEANS Conference
,
Vancouver, BC, Canada
,
Sept. 29–Oct. 4
, pp.
1989
1998
.
3.
Gaudin
,
C.
,
O’Loughlin
,
C. D.
,
Hossain
,
M. S.
, and
Zimmerman
,
E. H.
,
2013
, “
The Performance of Dynamically Embedded Anchors in Calcareous Silt
,”
ASME 2013 32nd International Conference on Ocean, Offshore and Arctic Engineering
,
Nantes, France
,
June 9–14
.
4.
Liu
,
J.
,
Han
,
C. C.
, and
Yu
,
L.
,
2019
, “
Experimental Investigation of the Keying Process of OMNI-Max Anchor
,”
Mar. Georesour. Geotechnol.
,
37
(
3
), pp.
349
365
.
5.
Liu
,
J.
,
Lu
,
L. H.
, and
Yu
,
L.
,
2014
, “
Large Deformation Finite Element Analysis of Gravity Installed Anchors in Clay
,”
ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering
,
San Francisco, CA
,
June 8–13
.
6.
Liu
,
J.
,
Lu
,
L. H.
, and
Hu
,
Y. X.
,
2016
, “
Keying Behavior of Gravity Installed Plate Anchor in Clay
,”
Ocean Eng.
,
114
, pp.
10
24
.
7.
Wei
,
Q. C.
,
Tian
,
Y. H.
,
Cassidy
,
M. J.
,
Gaudin
,
C.
, and
O’Loughlin
,
C. D.
,
2015
, “
Behaviour of OMNI-Max Anchors Under Chain Loading
,”
Frontiers in Offshore Geotechnics III: Proceedings of the 3rd International Symposium on Frontiers in Offshore Geotechnics (ISFOG 2015)
,
Oslo, Norway
,
June 10
.
8.
Kim
,
Y. H.
, and
Hossain
,
M. S.
,
2017
, “
Dynamic Installation, Keying and Diving of OMNI-Max Anchors in Clay
,”
Geotechnique
,
67
(
1
), pp.
78
85
.
9.
Han
,
C. C.
,
Liu
,
D. G.
, and
Liu
,
J.
,
2018
, “
Keying Process of the OMNI-Max Anchor Shallowly Embedded in Undrained Normally Consolidated Clay
,”
J. Waterway Port, Coastal Ocean Eng.
,
144
(
4
), p.
04018008
.
10.
Tian
,
Y. H.
,
Gaudin
,
C.
,
Randolph
,
M. F.
,
Cassidy
,
M. J.
, and
Peng
,
B.
,
2018
, “
Numerical Investigation of Diving Potential and Optimization of Offshore Anchors
,”
J. Geotech. Geoenviron. Eng.
,
144
(
2
), p.
04017117
.
11.
Zhao
,
Y. B.
, and
Liu
,
H. X.
,
2018
, “
Key Techniques in Simulating Comprehensive Anchor Behaviors by Large Deformation Finite Element Analysis
,”
ASME J. Offshore Mech. Arctic Eng.
,
140
(
1
), p.
012001
.
12.
Yang
,
Y. C.
,
Liu
,
H. X.
, and
Zhao
,
Y. B.
,
2021
, “
The Pullout Capacity of OMNI-Max Anchors in Clay
,”
Ocean Eng.
,
230
, p.
109063
.
13.
Kim
,
Y. H.
, and
Hossain
,
M. S.
,
2015
, “
Dynamic Installation of OMNI-Max Anchors in Clay: Numerical Analysis
,”
Geotechnique
,
65
(
12
), pp.
1029
1037
.
14.
Small
,
J. C.
,
Thorne
,
C. P.
, and
Ta
,
L. D.
,
1998
, “
Effect of Pore Pressure Dissipation on the Behaviour of Anchors in Clay
,”
The Eighth International Offshore and Polar Engineering Conference
,
Montreal, Canada
,
May 24–29
.
15.
Richards
,
D. J.
,
Rattley
,
M. J.
,
Lehane
,
B. M.
, and
Gaudin
,
C.
,
2005
, “
An Experimental Study and Numerical Study of Rate Effects for Plate Anchors in Clay
,”
Proceedings of the First International Symposium on Frontiers in Offshore Geotechnics
,
Perth, Australia
,
Sept. 19–21
.
16.
Singh
,
S. P.
,
Tripathy
,
D. P.
, and
Ramaswamy
,
S. V.
,
2007
, “
Estimation of Uplift Capacity of Rapidly Loaded Plate Anchors in Soft Clay
,”
Mar. Georesour. Geotechnol.
,
25
(
3–4
), pp.
237
249
.
17.
Richardson
,
M.
,
2008
,
Dynamically Installed Anchors for Floating Offshore Structures
,
The University of Western Australia
,
Perth, Australia
.
18.
Wang
,
D.
,
Hu
,
Y.
, and
Randolph
,
M. F.
,
2008
, “
Effect of Loading Rate on the Uplift Capacity of Plate Anchors
,”
The Eighteenth International Offshore and Polar Engineering Conference
,
Vancouver, Canada
,
July 6–11
.
19.
Wang
,
C.
,
Wang
,
X.
,
Chen
,
X.
, and
Yu
,
G. L.
,
2020
, “
Maximum Vertical Pullout Force of Torpedo Anchors in Cohesive Seabeds at Different Steady Pullout Velocities
,”
J. Coastal Res.
,
36
(
5
), pp.
1068
1078
.
20.
Briaud
,
J.
, and
Garland
,
E.
,
1985
, “
Loading Rate Method for Pile Response in Clay
,”
J. Geotech. Eng.
,
111
(
3
), pp.
319
335
.
21.
Vivatrat
,
V.
, and
Chen
,
V. L.
,
1985
, “
Strain-Rate and Forces Due to Mudflow Around Piles
,”
Proceedings of the 17th Annual Offshore Technology Conference
,
Houston, TX
,
May 6–9
.
22.
Al-Mhaidib
,
A. I.
,
2001
, “
Loading Rate Effect on Piles in Clay From Laboratory Model Tests
,”
J. King Saud Univ. Eng. Sci.
,
13
(
1
), pp.
39
54
.
23.
Lehane
,
B. M.
,
Gaudin
,
C.
,
Richards
,
D. J.
, and
Rattley
,
M. J.
,
2008
, “
Rate Effects on the Vertical Uplift Capacity of Footings Founded in Clay
,”
Geotechnique
,
58
(
1
), pp.
13
21
.
24.
Sun
,
L. Q.
,
Qi
,
Y. M.
,
Feng
,
X. W.
, and
Liu
,
Z. Q.
,
2020
, “
Tensile Capacity of Offshore Bucket Foundations in Clay
,”
Ocean Eng.
,
197
, p.
106893
.
25.
Vicent
,
S.
,
Kim
,
S. R.
,
Tung
,
D. V.
, and
Bong
,
T.
,
2020
, “
Effect of Loading Rate on the Pullout Capacity of Offshore Bucket Foundations in Sand
,”
Ocean Eng.
,
210
, p.
107427
26.
Aubeny
,
C. P.
, and
Shi
,
H.
,
2007
, “
Effect of Rate-Dependent Soil Strength on Cylinders Penetrating Into Soft Clay
,”
IEEE J. Ocean. Eng.
,
32
(
1
), pp.
49
56
.
27.
Williams
,
E. S.
,
Byrne
,
B. W.
, and
Blakeborough
,
A.
,
2013
, “
Pipe Uplift in Saturated Sand: Rate and Density Effects
,”
Geotechnique
,
63
(
11
), pp.
946
956
.
28.
Sheil
,
B. B.
,
Byrne
,
B. W.
, and
Martin
,
C. M.
,
2021
, “
Rate Effects on the Uplift Capacity of Pipelines Embedded in Clay: Finite Element Modelling
,”
Comput. Geotech.
,
137
, p.
104155
.
29.
Det Norske Veritas
,
2000
, “
Design and Installation of Fluke Anchors in Clay
,” DNV Recommended Practice RP-E301.
30.
Det Norske Veritas
,
2002
, “
Design and Installation of Plate Anchors in Clay
,” DNV Recommended Practice RP-E302.
31.
Det Norske Veritas
,
2005
, “
Geotechnical Design and Installation of Suction Anchors in Clay
,” DNV Recommended Practice RP-E303.
32.
Medeiros
,
C. J.
,
2002
, “
Low Cost Anchor System for Flexible Risers in Deep Waters
,”
Offshore Technology Conference
,
Houston, TX
,
May 6–9
.
33.
de Sousa
,
J. R. M.
,
de Aguiar
,
C. S.
,
Ellwanger
,
G. B.
,
Porto
,
E. C.
,
Foppa
,
D.
, and
de Medeiros
,
C. J.
,
2011
, “
Undrained Load Capacity of Torpedo Anchors Embedded in Cohesive Soils
,”
ASME J. Offshore Mech. Arct. Eng.
,
133
(
2
), p.
021102
.
34.
Wang
,
D.
, and
O’Loughlin
,
C. D.
,
2014
, “
Numerical Study of Pull-Out Capacities of Dynamically Embedded Plate Anchors
,”
Can. Geotech. J.
,
51
(
11
), pp.
1263
1272
.
35.
O’Beirne
,
C.
,
O’Loughlin
,
C. D.
,
Wang
,
D.
, and
Gaudin
,
C.
,
2015
, “
Capacity of Dynamically Installed Anchors as Assessed Through Field Testing and Three-Dimensional Large-Deformation Finite Element Analyses
,”
Can. Geotech. J.
,
52
(
5
), pp.
548
562
.
36.
Zhao
,
Y. B.
, and
Liu
,
H. X.
,
2015
, “
The Drag Effects on the Penetration Behavior of Drag Anchors During Installation
,”
Ocean Eng.
,
109
, pp.
169
180
.
37.
Kim
,
Y. H.
, and
Hossain
,
M. S.
,
2016
, “
Numerical Study on Pull-Out Capacity of Torpedo Anchors in Clay
,”
Geotech. Lett.
,
6
(
4
), pp.
275
282
.
38.
Fu
,
Y.
,
Zhang
,
X. Y.
,
Li
,
Y. P.
,
Gu
,
H.
,
Sun
,
J.
,
Liu
,
Y.
, and
Lee
,
F. H.
,
2017
, “
Holding Capacity of Dynamically Installed Anchors in Normally Consolidated Clay Under Inclined Loading
,”
Can. Geotech. J.
,
54
(
9
), pp.
1257
1271
.
39.
Wang
,
C.
,
Chen
,
X. H.
, and
Yu
,
G. L.
,
2019
, “
Maximum Force of Inclined Pullout of a Torpedo Anchor in Cohesive Beds
,”
China Ocean Eng.
,
33
(
3
), pp.
333
343
.
40.
Zhao
,
Y. B.
, and
Liu
,
H. X.
,
2017
, “
Toward a Quick Evaluation of the Performance of Gravity Installed Anchors in Clay: Penetration and Keying
,”
Appl. Ocean Res.
,
69
, pp.
148
159
.
41.
Sheahan
,
T. C.
,
Ladd
,
C. C.
, and
Germaine
,
J. T.
,
1996
, “
Rate-Dependent Undrained Shear Behavior of Saturated Clay
,”
J. Geotech. Eng.
,
122
(
2
), pp.
99
108
.
42.
Biscontin
,
G.
, and
Pestana
,
J. M.
,
2001
, “
Influence of Peripheral Velocity on Vane Shear Strength of an Artificial Clay
,”
Geotech. Test. J.
,
24
(
4
), pp.
423
429
.
43.
Einav
,
I.
, and
Randolph
,
M. F.
,
2006
, “
Effect of Strain Rate on Mobilised Strength and Thickness of Curved Shear Bands
,”
Geotechnique
,
56
(
7
), pp.
501
504
.
44.
Chow
,
S. H.
,
O’Loughlin
,
C. D.
, and
Randolph
,
M. F.
,
2014
, “
Soil Strength Estimation and Pore Pressure Dissipation for Free-Fall Piezocone in Soft Clay
,”
Geotechnique
,
64
(
10
), pp.
817
827
.
45.
Boukpeti
,
N.
,
White
,
D. J.
,
Randolph
,
M. F.
, and
Low
,
H. E.
,
2012
, “
Strength of Fine-Grained Soils at the Solid-Fluid Transition
,”
Geotechnique
,
62
(
3
), pp.
213
226
.
46.
Einav
,
I.
, and
Randolph
,
M. F.
,
2005
, “
Combining Upper Bound and Strain Path Methods for Evaluating Penetration Resistance
,”
Int. J. Numer. Meth. Eng.
,
63
(
14
), pp.
1991
2016
.
47.
Zhu
,
H. X.
, and
Randolph
,
M. F.
,
2011
, “
Numerical Analysis of a Cylinder Moving Through Rate-Dependent Undrained Soil
,”
Ocean Eng.
,
38
(
7
), pp.
943
953
.
48.
Glasstone
,
S.
,
Laidler
,
K.
, and
Eyring
,
H.
,
1941
,
The Theory of Rate Processes
,
McGraw-Hill
,
New York
.
49.
Soga
,
K.
, and
Mitchell
,
J.
,
2005
,
Fundamentals of Soil Behavior
, 3rd ed.,
John Wiley & Sons
,
New York
.
50.
Gao
,
Y. B.
, and
Wang
,
Z. W.
,
2005
, “
Effect of Strain Rate on Undrained Shear Strength of Clays
,”
Chin. J. Rock Mech. Eng.
,
24
, pp.
5779
5783
.
51.
Wang
,
L.
, and
Shen
,
K. L.
,
2007
, “
A Constitutive Model of K0 Consolided Structured Soft Clays
,”
Chin. J. Geotech. Eng.
,
29
(
004
), pp.
496
504
.
52.
Wan
,
Z.
,
1985
, “
Bed Material Movement in Hyperconcentrated Flow
,”
J. Hydraul. Eng.
,
111
(
6
), pp.
987
1002
.
53.
Coussot
,
P.
,
Laigle
,
D.
,
Arattano
,
M.
,
Deganutti
,
A.
, and
Marchi
,
L.
,
1998
, “
Direct Determination of Rheological Characteristics of Debris Flow
,”
J. Hydraul. Eng.
,
124
(
8
), pp.
865
868
.
54.
Graham
,
J.
,
Crooks
,
J.
, and
Bell
,
A. L.
,
1983
, “
Time Effects on the Stress-Strain Behaviour of Natural Soft Clays
,”
Geotechnique
,
33
(
3
), pp.
327
340
.
55.
Dayal
,
U.
, and
Allen
,
J. H.
,
1975
, “
The Effect of Penetration Rate on the Strength of Remolded Clay and Sand Samples
,”
Can. Geotech. J.
,
12
(
3
), pp.
336
348
.
56.
Kim
,
Y. H.
,
Hossain
,
M. S.
, and
Wang
,
D.
,
2015
, “
Effect of Strain Rate and Strain Softening on Embedment Depth of a Torpedo Anchor in Clay
,”
Ocean Eng.
,
108
, pp.
704
715
.
57.
Kim
,
Y. H.
,
Hossain
,
M. S.
,
Wang
,
D.
, and
Randolph
,
M. F.
,
2015
, “
Numerical Investigation of Dynamic Installation of Torpedo Anchors in Clay
,”
Ocean Eng.
,
108
, pp.
820
832
.
58.
Han
,
C. C.
,
Liu
,
J.
,
Zhang
,
Y. Q.
, and
Zhao
,
W.
,
2019
, “
An Innovative Booster for Dynamic Installation of OMNI-Max Anchors in Clay: Physical Modelling
,”
Ocean Eng.
,
171
, pp.
345
360
.
59.
Zhou
,
H. X.
, and
Randolph
,
M. F.
,
2009
, “
Resistance of Full-Flow Penetrometers in Rate-Dependent and Strain-Softening Clay
,”
Geotechnique
,
59
(
2
), pp.
79
86
.
60.
Hossain
,
M. S.
,
O’Loughlin
,
C. D.
, and
Kim
,
Y.
,
2015
, “
Dynamic Installation and Monotonic Pullout of a Torpedo Anchor in Calcareous Silt
,”
Geotechnique
,
65
(
2
), pp.
77
90
.
61.
Noh
,
W. F.
,
1963
, “CEL: A Time-Dependent, Two-Space-Dimensional, Coupled Eulerian-Lagrange Code,”
Methods Incomputational Physics
,
B.
Alder
,
S.
Fernbach
,
M.
Rotenberg
, eds.,
Lawrence Radiation Laboratory, University of California
,
Livermore, CA
.
62.
Benson
,
D. J.
,
1992
, “
Computational Methods in Lagrangian and Eulerian Hydrocodes
,”
Comput. Meth. Appl. Mech. Eng.
,
99
(
2–3
), pp.
235
394
.
63.
Liu
,
H. X.
,
Su
,
F. M.
, and
Li
,
Z.
,
2014
, “
The Criterion for Determining the Ultimate Pullout Capacity of Plate Anchors in Clay by Numerical Analysis
,”
Am. J. Eng. Appl. Sci.
,
7
(
4
), pp.
374
386
.
64.
Hossain
,
M. S.
,
Kim
,
Y.
, and
Wang
,
D.
,
2013
, “
Physical and Numerical Modelling of Installation and Pull-Out of Dynamically Penetrating Anchors in Clay and Silt
,”
ASME 2013 32nd International Conference on Ocean, Offshore and Arctic Engineering
,
Nantes, France
,
June 9–14
.
65.
Ginat
,
D.
,
2003
, “
Decomposition Diversity in Computer Science-Beyond the Top-Down Icon
,”
J. Comput. Math. Sci. Teach.
,
22
(
4
), pp.
365
379
.
66.
Najafi
,
A.
,
Niu
,
N.
, and
Najafi
,
F.
,
2011
, “
Multi-Level Decomposition Approach for Problem Solving and Design in Software Engineering
,”
Southeast Regional Conference
,
Kennesaw, GA
,
Mar. 24–26
.
67.
Poulos
,
H. G.
,
1988
,
Marine Geotechnics
,
Unwin Hyman
,
London
.
68.
Liu
,
J.
,
Tan
,
M. X.
, and
Hu
,
Y. X.
,
2018
, “
New Analytical Formulas to Estimate the Pullout Capacity Factor for Rectangular Plate Anchors in NC Clay
,”
Appl. Ocean Res.
,
75
, pp.
234
247
.
69.
Zhao
,
Y. B.
, and
Liu
,
H. X.
,
2016
, “
Numerical Implementation of the Installation/Mooring Line and Application to Analyzing Comprehensive Anchor Behaviors
,”
Appl. Ocean Res.
,
54
, pp.
101
114
.
70.
Hu
,
Y.
, and
Randolph
,
M. F.
,
1998
, “
A Practical Numerical Approach for Large Deformation Problems in Soil
,”
Int. J. Numer. Anal. Meth. Geomech.
,
22
(
5
), pp.
327
350
.
71.
Song
,
Z.
,
Hu
,
Y.
, and
Randolph Mark
,
F.
,
2008
, “
Numerical Simulation of Vertical Pullout of Plate Anchors in Clay
,”
J. Geotech. Geoenviron. Eng.
,
134
(
6
), pp.
866
875
.
72.
Yu
,
L.
,
Liu
,
J.
,
Kong
,
X. J.
, and
Hu
,
Y.
,
2011
, “
Numerical Study on Plate Anchor Stability in Clay
,”
Geotechnique
,
61
(
3
), pp.
235
246
.
73.
Bhattacharya
,
P.
,
2016
, “
Pullout Capacity of Strip Plate Anchor in Cohesive Sloping Ground Under Undrained Condition
,”
Comput. Geotech.
,
78
, pp.
134
143
.
74.
Bhattacharya
,
P.
,
2017
, “
Pullout Capacity of Shallow Inclined Anchor in Anisotropic and Nonhomogeneous Undrained Clay
,”
Geomech. Eng.
,
13
(
5
), pp.
825
844
.
75.
Singh
,
V.
,
Maitra
,
S.
, and
Chatterjee
,
S.
,
2017
, “
Generalized Design Approach for Inclined Strip Anchors in Clay
,”
Int. J. GeoMech.
,
17
(
6
), p.
04016148
.
You do not currently have access to this content.