|Table of Contents|

Citation:
　Zhenkun Liao,Yuliang Zhao,Sheng Dong.Estimating Design Loads for Floating Structures Using Environmental Contours[J].Journal of Marine Science and Application,2022,(3):114-127.[doi:10.1007/s11804-022-00282-x]
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Estimating Design Loads for Floating Structures Using Environmental Contours

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Title:
Estimating Design Loads for Floating Structures Using Environmental Contours
Author(s):
Zhenkun Liao;  Yuliang Zhao;  Sheng Dong
Affilations:
Author(s):
Zhenkun Liao;  Yuliang Zhao;  Sheng Dong
College of Engineering, Ocean University of China, Qingdao, 266100, China
Keywords:
Design loads|Mooring system|IFORM-based approach|Copulas|Nataf transformation|Short/long-term extreme response
分类号:
-
DOI:
10.1007/s11804-022-00282-x
Abstract:
Nonlinear time-domain simulations are often used to predict the structural response at the design stage to ensure the acceptable operation and/or survival of floating structures under extreme conditions. An environmental contour (EC) is commonly employed to identify critical sea states that serve as the input for numerical simulations to assess the safety and performance of marine structures. In many studies, marginal and conditional distributions are defined to construct bivariate joint probability distributions for variables, such as significant wave height and zero-crossing period. Then, ECs can be constructed using the inverse first-order reliability method (IFORM). This study adopts alternative models to describe the generalized dependence structure between environmental variables using copulas and discusses the Nataf transformation as a special case. ECs are constructed using measured wave data from moored buoys. Derived design loads are applied on a semisubmersible platform to assess possible differences. In addition, a linear interpolation scheme is utilized to establish a parametric model using short-term extreme tension distribution parameters and wave data, and the long-term tension response is estimated using Monte Carlo simulation. A 3D IFORM-based approach, in which the short-term extreme response that is ignored in the EC approach is used as the third variable, is proposed to help establish accurate design loads with increased accuracy. Results offer a clear illustration of the extreme responses of floating structures based on different models.

References:

Agarwal P, Manuel L (2009) Simulation of offshore wind turbine response for long-term extreme load prediction. Engineering Structures 31:2236-2246. DOI:10.1016/j.engstruct.2009.04.002
Baarholm GS, Haver S, ?kland OD (2010) Combining contours of significant wave height and peak period with platform response distributions for predicting design response. Marine Structures 23:147-163. DOI:10.1016/j.marstruc.2010.03.001
Belberova D, Myrhaug D (1996) Critical assessment of the joint occurrence of wind and waves at a buoy station off the southern Norwegian coast. Journal of Wind Engineering and Industrial Aerodynamics 61(2-3):207-224. DOI:10.1016/0167-6105(96) 00050-5
Bitner-Gregersen EM (2005) Joint probabilistic description for combined seas. Proceedings of the 24th International Conference on Offshore Mechanics and Arctic Engineering, Halkidiki, Greece, 169-180
Bitner-Gregersen EM (2015) Joint met-ocean description for design and operations of marine structures. Applied Ocean Research 51:279-292. DOI:10.1016/j.apor.2015.01.007
Chai W, Leira BJ (2018) Environmental contours based on inverse SORM. Marine Structures 60:34-51. DOI:10.1016/j.marstruc. 2018.03.007
DNV (2012) Environmental conditions and environmental loads. DNV-RP-C205. Det Norske Veritas, Oslo.
Dong S, Wang NN, Liu W, Guedes Soares C (2013) Bivariate maximum entropy distribution of significant wave height and peak period. Ocean Engineering, 59:86-99. DOI:10.1016/j. oceaneng.2012.12.002
Dong S, Chen CC, Tao SS (2017) Joint probability design of marine environmental elements for wind turbines. International Journal of Hydrogen Energy 42:18595-18601. DOI:10.1016/j.ijhydene. 2017.04.154
Eckert-Gallup AC, Sallaberry CJ, Dallman AR, Neary VS (2016) Application of principal component analysis (PCA) and improved joint probability distributions to the inverse first-order reliability method (I-FORM) for predicting extreme sea states. Ocean Engineering 112:307-319. DOI:10.1016/j.oceaneng.2015.12.018
Haselsteiner AF, Coe RG, Manuel L, Nguyen PTT, Martin N, EckertGallup A (2019) A benchmarking exercise on estimating extreme environmental conditions:Methodology & baseline results. Proceeding of 38th International Conference on Ocean, Offshore and Arctic Engineering, Glasgow, Scotland, OMAE2019-96523
Haver S (1985) Wave climate off northern Norway. Applied Ocean Research 7:85-92. DOI:10.1016/0141-1187(85)90038-0
Haver S, Winterstein SR (2009) Environmental contour lines:a method for estimating long term extremes by a short term analysis. Transactions-Society of Naval Architects and Marine Engineers 116:116-127.
Huseby AB, Vanem E, Natvig B (2013) A new approach to environmental contours for ocean engineering applications based on di-rect Monte Carlo simulations. Ocean Engineering 60:124-135.DOI:10.1016/j.oceaneng.2012.12.034
Jonathan P, Ewans K (2013) Statistical modelling of extreme ocean environments for marine design:a review. Ocean Engineering 62:91-109. DOI:10.1016/j.oceaneng.2013.01.004
Liu J, Thomas E, Goyal A, Manuel L (2019) Design loads for a large wind turbine supported by a semi-submersible floating platform.Renewable Energy 138:923-936. DOI:10.1016/j.renene.2019.02.011
Manuel L, Nguyen PTT, Canning J, Coe RG, Eckert-Gallup AC, Martin N (2018) Alternative approaches to develop environmental contours from metocean data. Journal of Ocean Engineering and Marine Energy 4:293-310. DOI:10.1007/s40722-018-0123-0
Montes-Iturrizaga R, Heredia-Zavoni E (2015) Environmental contours using copulas. Applied Ocean Research 52:125-139. DOI:10.1016/j.apor.2015.05.007
Nelsen RB (2006) An introduction to copulas. 2nd ed, Springer, New York, 109-115
Ross E, Astrup OC, Bitner-Gregerson E, Bunn N, Feld G, Gouldby B, Huseby A, Liu Y, Randell D, Vanem E, Jonthan P (2020) Review on environmental contours for marine and coastal design. Ocean Engineering 195:106194. DOI:10.1016/j.oceaneng.2019.106194
Saranyasoontorn K, Manuel L (2004) Efficient models for wind turbine extreme loads using inverse reliability. Journal of Wind Engineering and Industrial Aerodynamics 92:789-804. DOI:10.1016/j.jweia.2004.04.002
Silva-González FL, Heredia-Zavoni E, Montes-Iturrizaga R (2013) Development of environmental contours using Nataf distribution model. Ocean Engineering 58:27-34. DOI:10.1016/j.oceaneng. 2012.08.008
Sklar A (1959) Fonctions de Répartition à n Dimensions Etleursmarges. Publications de l’Institut de Statistique de l’Université de Paris, Paris, 229-231
Stanisic D, Efthymiou M, Kimiaei M, Zhao WH (2018) Design loads and long term distribution of mooring line response a large weathervaning vessel in a tropical cyclone environment. Marine Structures 61:361-380. DOI:10.1016/j.marstruc.2018.06.004
Tao SS, Dong S, Xu YH (2013) Design parameters estimation of wave height and wind speed with bivariate copulas. Proceedings of the 32nd ASME International Conference on Ocean, Offshore and Arctic Engineering, Nantes, France, OMAE2013-10519
Vanem E, Bitner-Gregersen E (2012) Stochastic modelling of longterm trends in the wave climate and its potential impact on ship structural loads. Applied Ocean Research 37:235-248. DOI:10.1016/j.apor.2012.05.006
Vanem E (2016a) Copula-based bivariate modelling of significant wave height and wave period and the effects of climate change on the joint distribution. Proceeding of the 35th International Conference on Ocean, Offshore and Arctic Engineering, Busan, South Korea, OMAE2016-54314.
Vanem E (2016b) Joint statistical models for significant wave height and wave period in a changing climate. Marine Structures 49:180-205. DOI:10.1016/j.marstruc.2016.06.001
Vanem E, Gramstad O, Bitner-Gregersen EM (2019) A simulation study on the uncertainty of environmental contours due to sampling variability for different estimation methods. Applied Ocean Research 91:101870. DOI:10.1016/j.apor.2019.101870
Vanem E, Huseby AB (2020) Environmental contours based on a direct sampling approach and the IFORM approach:Contribution to a benchmark study. Proceeding of 39th International Conference on Ocean, Offshore and Arctic Engineering
Vázquez-Hernández AO, Ellwanger GB, Sagrilo LVS (2011) Longterm response analysis of FPSO mooring systems. Applied Ocean Research 33:375-383. DOI:10.1016/j.apor.2011.05.003
Velarde J, Vanem E, Kramhøft C, Sørensen JD (2019) Probabilistic analysis of offshore wind turbines under extreme resonant response:Application of environmental contour method. Applied Ocean Research 93:101947. DOI:10.1016/j.apor.2019.101947
Venter GG (2002) Tails of copulas. Proc Casualty Actuar Soc 89(171):68-113
Winterstein SR, Ude TC, Cornell CA, Bjerager P, Haver S (1993) En-vironmental parameters for extreme response:Inverse FORM with omission factors. Proceedings of the 6th International Con-ference on Structural Safety & Reliability (ICOSSAR), Inns-bruck, Austria
Xu S, Ji CY, Guedes Soares C (2019) Estimation of short-term extreme responses of a semi-submersible moored by two hybrid mooring systems. Ocean Engineering 190:106388. DOI:10.1016/j.oceaneng.2019.106388

Memo

Memo:
Received date:2022-05-15;Accepted date:2022-06-29。
Foundation item:Supported by the National Natural Science Foundation of China under Grant No. 52171284.
Corresponding author:Sheng Dong,E-mail:dongsh@ouc.edu.cn
Last Update: 2022-10-09