0
Research Papers: Ocean Renewable Energy

Assessment of Allowable Sea States During Installation of Offshore Wind Turbine Monopiles With Shallow Penetration in the Seabed

[+] Author and Article Information
Lin Li

Centre for Ships and Ocean Structures (CeSOS),
Centre for Autonomous Marine Operations and Systems (AMOS),
Department of Marine Technology,
Norwegian University of Science and Technology (NTNU),
Trondheim NO-7491, Norway
e-mail: lin.li@ntnu.no

Wilson Guachamin Acero, Zhen Gao, Torgeir Moan

Centre for Ships and Ocean Structures (CeSOS),
Centre for Autonomous Marine Operations and Systems (AMOS),
Department of Marine Technology,
Norwegian University of Science and Technology (NTNU),
Trondheim NO-7491, Norway

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 December 21, 2015; final manuscript received April 20, 2016; published online June 1, 2016. Assoc. Editor: Yi-Hsiang Yu.

J. Offshore Mech. Arct. Eng 138(4), 041902 (Jun 01, 2016) (17 pages) Paper No: OMAE-15-1128; doi: 10.1115/1.4033562 History: Received December 21, 2015; Revised April 20, 2016

Installation of offshore wind turbines (OWTs) requires careful planning to reduce costs and minimize associated risks. The purpose of this paper is to present a method for assessing the allowable sea states for the initial hammering process (shallow penetrations in the seabed) of a monopile (MP) using a heavy lift floating vessel (HLV) for use in the planning of the operation. This method combines the commonly used installation procedure and the time-domain simulations of the sequential installation activities. The purpose of the time-domain simulation is to quantitatively study the system dynamic responses to identify critical events that may jeopardize the installation and the corresponding limiting response parameters. Based on the allowable limits and the characteristic values of the limiting response parameters, a methodology to find the allowable sea states is proposed. Case studies are presented to show the application of the methodology. The numerical model of the dynamic HLV–MP system includes the coupling between HLV and MP via a gripper device, and soil–MP interaction at different MP penetration depths. It is found that the limiting parameters are the gripper force and the inclination of the MP. The systematic approach proposed herein is general and applies to other marine operations.

Copyright © 2016 by ASME
Your Session has timed out. Please sign back in to continue.

References

EWEA, 2014, “ The European Offshore Wind Industry—Key Trends and Statistics 2013,” Report, The European Wind Energy Association, Brussels, Belgium.
Thomsen, K. , 2011, Offshore Wind: A Comprehensive Guide to Successful Offshore Wind Farm Installation, Academic Press, Waltham, MA.
Ringsberg, J. W. , Daun, V. , and Olsson, F. , 2015, “ Analysis of Impact Loads on a Self-Elevating Unit During Jacking Operation,” ASME Paper No. OMAE2015-41030.
Sarkar, A. , and Gudmestad, O. , 2013, “ Study on a New Method for Installing a Monopile and a Fully Integrated Offshore Wind Turbine Structure,” Mar. Struct., 33, pp. 160–187. [CrossRef]
Li, L. , Gao, Z. , and Moan, T. , 2013, “ Numerical Simulations for Installation of Offshore Wind Turbine Monopiles Using Floating Vessels,” ASME Paper No. OMAE2013-11200.
Li, L. , Gao, Z. , Moan, T. , and Ormberg, H. , 2014, “ Analysis of Lifting Operation of a Monopile for an Offshore Wind Turbine Considering Vessel Shielding Effects,” Mar. Struct., 39, pp. 287–314. [CrossRef]
Li, L. , Gao, Z. , and Moan, T. , 2015, “ Comparative Study of Lifting Operations of Offshore Wind Turbine Monopile and Jacket Substructures Considering Shielding Effects,” 25th International Offshore and Polar Engineering Conference, June 21–26, Kona, HI.
Li, L. , Gao, Z. , and Moan, T. , 2015, “ Response Analysis of a Nonstationary Lowering Operation for an Offshore Wind Turbine Monopile Substructure,” ASME J. Offshore Mech. Arctic Eng., 137(5), p. 051902. [CrossRef]
Smith, C. , 2014, Offshore Piles on the Straight and Narrow, Last accessed on July 15, 2015, http:// www.nce.co.uk/news/geotechnical/offshore-piles-on-the-straight-and-narrow/8663331.article.
Strandgaard, T. , and Vandenbulcke, L. , 2002, “Driving Mono-Piles Into Glacial Till,” IBCs Wind Power Europe.
DNV, 2011, “ Marine Operations,” General, Det Norske Veritas, Oslo, Norway, Offshore Standard DNV-OS-H101.
MARINTEK, 2012, SIMO—Theory Manual Version 4.0, MARINTEK, Trondheim, Norway.
Newman, J. N. , 1974, “ Second-Order, Slowly-Varying Forces on Vessels in Irregular Waves,” International Symposium on the Dynamics of Marine Vehicles and Structures in Waves, University College, London.
Lee, C. , 1995, WAMIT Theory Manual, Department of Ocean Engineering, Massachusetts Institute of Technology, Cambridge, MA.
DNV, 2010, “ Environmental Conditions and Environmental Loads,” Det Norske Veritas, Oslo, Norway, Recommended Practice DNV-RP-C205.
Albers, P. , 2010, Motion Control in Offshore and Dredging, Springer Science & Business Media, Verlag, Germany.
Carswell, W. , Johansson, J. , Løvholt, F. , Arwade, S. , Madshus, C. , DeGroot, D. , and Myers, A. , 2015, “ Foundation Damping and the Dynamics of Offshore Wind Turbine Monopiles,” Renewable Energy, 80, pp. 724–736. [CrossRef]
Bisoi, S. , and Haldar, S. , 2014, “ Dynamic Analysis of Offshore Wind Turbine in Clay Considering Soil Monopile Tower Interaction,” Soil Dyn. Earthquake Eng., 63, pp. 19–35. [CrossRef]
Andersen, L. V. , Vahdatirad, M. , Sichani, M. T. , and Sørensen, J. D. , 2012, “ Natural Frequencies of Wind Turbines on Monopile Foundations in Clayey Soils a Probabilistic Approach,” Comput. Geotech., 43, pp. 1–11. [CrossRef]
Gerolymos, N. , and Gazetas, G. , 2006, “ Development of Winkler Model for Static and Dynamic Response of Caisson Foundations With Soil and Interface Nonlinearities,” Soil Dyn. Earthquake Eng., 26(5), pp. 363–376. [CrossRef]
Ong, M. , Li, H. , Leira, B. J. , and Myrhaug, D. , 2013, “ Dynamic Analysis of Offshore Monopile Wind Turbine Including the Effects of Wind–Wave Loading and Soil Properties,” ASME Paper No. OMAE2013-10527.
DNV, 2014, “ Design of Offshore Wind Turbine Structures,” Det Norske Veritas, Oslo, Norway, Offshore Standard DNV-OS-J101.
API, 2007, “ Recommended Practice for Planning, Designing and Constructing Fixed Offshore Platforms Working Stress Design,” American Petroleum Institute, Washington DC, API Recommended Practice 2A-WSD (RP 2A-WSD).
Byrne, B. , McAdam, R. , Burd, H. , Houlsby, G. , Martin, C. , Zdravkovi, L. , Taborda, D. , Potts, D. , Jardine, R. , and Sideri, M. , 2015, “ New Design Methods for Large Diameter Piles Under Lateral Loading for Offshore Wind Applications,” 3rd International Symposium on Frontiers in Offshore Geotechnics (ISFOG 2015), Oslo, Norway, June 10–12.
Lesny, K. , and Wiemann, J. , 2006, “ Finite-Element-Modelling of Large Diameter Monopiles for Offshore Wind Energy Converters,” Geo Congress, Feb. 26–Mar. 1, Atlanta, GA.
Hededal, O. , and Klinkvort, R. T. , 2010, “ A New Elasto-Plastic Spring Element for Cyclic Loading of Piles Using the py Curve Concept,” Numerical Methods in Geotechnical Engineering, Benz and Nordal, eds., Taylor & Francis Group, London, pp. 883–888.
Bekken, L. , 2009, “ Lateral Behavior of Large Diameter Offshore Monopile Foundations for Wind Turbines,” Ph.D. thesis, TU Delft, Delft University of Technology, Netherlands.
Lombardi, D. , Bhattacharya, S. , and Wood, D. M. , 2013, “ Dynamic Soil-Structure Interaction of Monopile Supported Wind Turbines in Cohesive Soil,” Soil Dyn. Earthquake Eng., 49, pp. 165–180. [CrossRef]
Vemula, N. K. , de Vries, W. , Fischer, T. , Cordle, A. , and Schmidt, B. , 2010, “ Design Solution for the Upwind Reference Offshore Support Structure, Deliverable D4.2.5,” Technical Report, Project Upwind, WP4: Offshore Foundations and Support Structures.
ANSYS, 2011, The AQWA Reference Manual—Version 14.0. ANSYS, Canonsburg, PA.
Young-Kwan Kim, J.-R. S. , and Yoon, D.-Y. , 2012, “ A Design of Windmill Turbine Installation Vessel Using Jack-Up System,” 22nd International Offshore and Polar Engineering Conference, June 17–22, Rhodes, Greece.
Naess, A. , 1984, “ Technical Note: On a Rational Approach to Extreme Value Analysis,” Appl. Ocean Res., 6(3), pp. 173–174. [CrossRef]
Naess, A. , 1984, “ On the Long-Term Statistics of Extremes,” Appl. Ocean Res., 6(4), pp. 227–228. [CrossRef]
Naess, A. , Gaidai, O. , and Teigen, P. S. , 2007, “ Extreme Response Prediction for Nonlinear Floating Offshore Structures by Monte Carlo Simulation,” Appl. Ocean Res., 29(4), pp. 221–230. [CrossRef]
IHC, 2015, “ IHC Vremac Cylinders—Cylinder Catalogue 210 bar /300 bar,” Last accessed: May 05, 2015, http://www.ihcvremaccylinders.com/

Figures

Grahic Jump Location
Fig. 1

System setup for the MP hammering process

Grahic Jump Location
Fig. 2

Flowchart of the MP hammering procedure

Grahic Jump Location
Fig. 3

Methodology to find the allowable sea states for the initial hammering process

Grahic Jump Location
Fig. 4

Elastic model of the gripper contact elements

Grahic Jump Location
Fig. 5

Numerical models for the soil–MP interactions

Grahic Jump Location
Fig. 6

Typical soil reaction moment versus MP inclination due to cyclic loading with period of 6 s

Grahic Jump Location
Fig. 7

Standard deviations of HLV motions at different MP penetration depths (pene) and wave conditions from 3-hr time-domain simulations (Hs = 1.5 m, Dir = 150 deg)

Grahic Jump Location
Fig. 8

Standard deviations of MP inclinations and contact forces on one hydraulic cylinder at different MP penetration depths (pene) and wave conditions from 3-hr time-domain simulations (Hs = 1.5 m, Dir = 150 deg)

Grahic Jump Location
Fig. 9

Response spectra of the gripper surge motion for two different wave peak periods at different MP penetration depths (pene): (a) Hs = 1.5 m, Tp = 5 s, Dir = 150 deg and (b) Hs = 1.5 m, Tp = 10 s, Dir = 150 deg

Grahic Jump Location
Fig. 10

Response spectra of the gripper sway motion for two different wave peak periods at different MP penetration depths (pene): (a) Hs = 1.5 m, Tp = 5 s, Dir = 150 deg and (b) Hs = 1.5 m, Tp = 10 s, Dir = 150 deg

Grahic Jump Location
Fig. 11

Response spectra of the HLV yaw motion for two different wave peak periods at different MP penetration depths (pene): (a) Hs = 1.5 m, Tp = 5 s, Dir = 150 deg and (b) Hs = 1.5 m, Tp = 10 s, Dir = 150 deg

Grahic Jump Location
Fig. 12

Response spectra of the hydraulic cylinder force for two different wave peak period conditions at different MP penetration depths (pene): (a) Hs = 1.5 m, Tp = 5 s, Dir = 150 deg and (b) Hs = 1.5 m, Tp = 10 s, Dir = 150 deg

Grahic Jump Location
Fig. 13

STD of hydraulic cylinder contact forces at different MP penetration depths (pene) when using a jack-up vessel (Hs = 1.5 m, Dir = 150 deg)

Grahic Jump Location
Fig. 14

p–y curves for different soil types

Grahic Jump Location
Fig. 15

Extreme cylinder force in 3 hrs versus MP maximum inclination in 10 min for different sea states and soil properties at different penetrations: (a) Hs = 2 m, Tp = 6 s and (b) Hs = 1.6 m, Tp = 8 s

Grahic Jump Location
Fig. 16

Mean upcrossing rate of the hydraulic cylinder force using 20 samples. Legends: time-domain simulation (*), curve fitting (–), empirical 95% confidence band (CI – – – ), smooth confidence band (CIextr · · · ): (a) Hs = 1.5 m, Tp = 6 s, pene = 4 m and (b) Hs = 1.5 m, Tp = 10 s, pene = 6 m

Grahic Jump Location
Fig. 17

Extreme cylinder forces in 3 hrs at different penetration depths (pene): (a) Hs = 0.8 m, Dir = 150 deg and (b) Hs = 1.5 m, Dir = 150 deg

Grahic Jump Location
Fig. 18

Illustration of the phases between hammering activities: (a) system mean position before hammering, (b) system position after hammering, (c) system equilibrium mean position after hammering, and (d) system mean position after correction

Grahic Jump Location
Fig. 19

Responses of the HLV–MP coupled system after hammering and during the correction phase (corresponds to Figs. 18(b) to 18(d))

Grahic Jump Location
Fig. 20

Correction forces at different penetration depths (pene) and initial mean inclinations

Grahic Jump Location
Fig. 21

Maximum MP inclination over 10 min at different penetration depths (pene): (a) Hs = 0.8 m, Dir = 150 deg and (b) Hs = 1.5 m, Dir = 150 deg

Grahic Jump Location
Fig. 22

Case studies: (a) case 1, (b) case 2, (c) case 3, and (d) case 4

Grahic Jump Location
Fig. 23

Allowable sea states for MP initial hammering operation for typical HLV headings

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In