A model of extreme environmental conditions for wind–wave–swell and related structural analysis
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摘要: 准确评估海洋工程结构的长期极限响应是确保其生存条件的基础,而外部环境条件种类不清晰是影响这一评估的关键因素。现有研究普遍倾向于将风与风浪等纳入优先考虑范围,但实际海况往往呈现出风浪与涌浪相互叠加的多模态特征。基于单峰波谱的波浪时程生成方法难以表征其多模态特性,也无法揭示风、风浪与涌浪三者之间的统计依赖性,导致环境变量联合分布复杂性被低估,从而影响后续结构可靠性和安全性。涌浪作为强度可与风浪相当的低频波,易激发海上风电这类柔性结构的低频共振,进而放大动力响应和累积疲劳损伤。国际电工委员会(IEC)今年发布的行业规范《IEC 61400-3-2:2025》以及全国风电标准化技术委员会牵头制定的《风能发电系统漂浮式海上风力发电机组一体化计算分析导则》均已明确将涌浪列为必须考虑的工况。因此,本文将涌浪作为与风、风浪并列的灾种,基于南海、东海、渤海和黄海典型站点的再分析气象数据,构建了三者的联合概率模型,并通过相关性分析、Granger因果检验和条件概率分析,揭示了不同海域的多灾害相关结构规律。最后,以南海为例,结合环境等值线法(ECM)构建了包含风、风浪与涌浪的极限环境模型。结果表明,纳入涌浪后,环境变量组合的复杂性显著增加;忽略涌浪将导致环境条件模型失真,并低估极端环境的强度。该研究通过在传统风、风浪基础上进一步引入涌浪,并分析了其作为灾种的必要性,一定程度上弥补了现有海洋环境条件种类不清晰的问题,为海洋结构的长期极限响应评估提供了完整且精准的环境输入模型。Abstract: Accurate assessment of a marine structure’s long-term extreme response is fundamental to its survivability, yet an unclear taxonomy of external environmental conditions hampers such assessments. While many studies prioritize wind and wind sea, real sea states are frequently multimodal, with wind sea and swell superposed. Unimodal-spectrum time-series methods cannot represent this multimodality or the statistical dependence among wind, wind sea, and swell, leading to underestimated joint extremes and biased reliability/safety evaluations. Swell—a low-frequency component whose intensity can rival wind sea—readily excites low-frequency resonance in flexible systems such as offshore wind turbines, amplifying dynamic responses and cumulative fatigue. Recent standards (IEC 61400-3-2: 2025 and China’s guideline for integrated analysis of floating offshore wind turbines) explicitly require swell to be treated as a mandatory load case. Accordingly, we treat swell as a co-equal hazard with wind and wind sea. Using reanalysis data from representative stations in the South China Sea, East China Sea, Bohai Sea, and Yellow Sea, we build a joint probabilistic model of the three drivers and, via correlation analysis, Granger causality tests, and conditional probability analysis, reveal region-specific dependence structures. For the South China Sea, the environmental contour method is then used to construct an extreme-environment model that explicitly includes swell. Results show that incorporating swell markedly increases the complexity of environmental-variable combinations; omitting it distorts the environmental model and underestimates extremes. By extending the conventional wind–wave framework to include swell and demonstrating its necessity as a hazard, the study clarifies condition categories and supplies a more complete and accurate environmental input for long-term extreme-response assessment.
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图 2 风、风浪、涌浪数据的条形图
a. 南海三亚“三峡引领号”海上风电场,b. 东海大桥海上风电场址,c. 黄海华能山东半岛北L场址海上风电场,d. 华能天津港东疆北防波堤风电场
Fig. 2 Bar charts of wind, wind-generated wave, and swell data
a. Sanya “Three Gorges Yinling” offshore wind farm, South China Sea; b. Donghai Bridge offshore wind farm site; c. Huaneng Shandong Peninsula North-L site offshore wind farm, Yellow Sea; d. Huaneng Tianjin Port Dongjiang north breakwater wind farm
图 5 Pearson相关性热图
a. 南海三亚“三峡引领号”海上风电场,b. 东海大桥海上风电场址,c. 黄海华能山东半岛北L场址海上风电场,d. 华能天津港东疆北防波堤风电场
Fig. 5 Hot-map of correlation Pearson coefficient
a. Sanya “Three Gorges Yinling” offshore wind farm, South China Sea; b. Donghai Bridge offshore wind farm site; c. Huaneng Shandong Peninsula North-L site offshore wind farm, Yellow Sea; d. Huaneng Tianjin Port Dongjiang north breakwater wind farm
图 7 GCT结果热图
a. 南海三亚“三峡引领号”海上风电场,b. 东海大桥海上风电场址,c. 黄海华能山东半岛北L场址海上风电场,d. 华能天津港东疆北防波堤风电场;NaN表无效的数值
Fig. 7 The heatmap of results of GCT
a. Sanya “Three Gorges Yinling” offshore wind farm, South China Sea; b. Donghai Bridge offshore wind farm site; c. Huaneng Shandong Peninsula North-L site offshore wind farm, Yellow Sea; d. Huaneng Tianjin Port Dongjiang north breakwater wind farm;NaN means not a number
图 8 南海三亚“三峡引领号”海上风电场不同涌浪强度下的条件概率密度函数
a. 平均风速和风浪有效波高,b. 风浪有效波高和平均周期
Fig. 8 Conditional joint PDF under the different swell intensity of Sanya “Three Gorges Yinling” offshore wind farm, South China Sea
a. Average wind speed with significant wave height of wind-generated wave; b. significant wave height and average period of wind-generated wave
图 9 东海大桥海上风电场址不同涌浪周期下的条件概率密度函数
a. 平均风速和风浪有效波高,b. 风浪有效波高和平均周期
Fig. 9 Conditional joint PDF under the different swell intensity of Donghai Bridge offshore wind farm site
a. Average wind speed with significant wave height of wind-generated wave; b. significant wave height and average period of wind-generated wave
表 1 平均风速高阶统计特征
Tab. 1 Higher-order statistical features of average wind speed
测点 峰度 偏度 南海 3.97 0.31 东海 3.43 0.49 黄海 2.97 0.55 渤海 3.78 0.76 表 2 Vine-Copula相关结构
Tab. 2 The Vine-Copula correlation structure
结构树 主节点 其他节点 s1 s2 s3 s4 s5 Tree 1 s1 — Joe (4.16) Gumbel (1.41) Gumbel (1.45) Gumbel (6.08) Tree 2 s2 — — Amhaq (0.41) SurGumbel (1.12) T (−0.21,11.49) Tree 3 s5 — — T (−0.34,8.51) Amhaq (−0.71) — Tree 4 s4 — — Gumbel (2.14) — — -
[1] 茹继平, 刘加平, 曲久辉, 等. 建筑、环境与土木工程[M]. 北京: 中国建筑工业出版社, 2011.Ru Jiping, Liu Jiaping, Qu Jiuhui, et al. Architecture Environmental and Civil Engineering[M]. Beijing: China Architecture & Building Press, 2011. [2] 林伊楠, 陶爱峰, 李雪丁, 等. 台湾海峡风涌浪分离方法研究[J]. 海洋学报, 2019, 41(11): 25−34.Lin Yinan, Tao Aifeng, Li Xueding, et al. Study on separation method of wind-wave and swell in the Taiwan Strait[J]. Haiyang Xuebao, 2019, 41(11): 25−34. [3] 周延东, 雷震名, 孙国民, 等. 涌浪基本理论研究综述[J]. 水道港口, 2016, 37(1): 1−6. doi: 10.3969/j.issn.1005-8443.2016.01.001Zhou Yandong, Lei Zhenming, Sun Guomin, et al. A review on basic theory research of swell[J]. Journal of Waterway and Harbor, 2016, 37(1): 1−6. doi: 10.3969/j.issn.1005-8443.2016.01.001 [4] 史宪莹, 张宁川. 混合浪作用下系泊船舶运动响应规律试验研究[J]. 水动力学研究与进展, 2011, 26(5): 574−580. doi: 10.3969/j.issn1000-4874.2011.05.008Shi Xianying, Zhang Ningchuan. Experimental study of a mooring ship’s motion responses in mixed waves[J]. Chinese Journal of Hydrodynamics, 2011, 26(5): 574−580. doi: 10.3969/j.issn1000-4874.2011.05.008 [5] Longuet-Higgins M S, Stewart R W. Changes in the form of short gravity waves on long waves and tidal currents[J]. Journal of Fluid Mechanics, 1960, 8(4): 565−583. doi: 10.1017/S0022112060000803 [6] Yang Shanghui, Deng Xiaowei, Zhang Mingming, et al. Effect of wave spectral variability on the dynamic response of offshore wind turbine considering soil-pile-structure interaction[J]. Ocean Engineering, 2023, 267: 113222. doi: 10.1016/j.oceaneng.2022.113222 [7] Ti Zilong, Wei Kai, Li Yongle, et al. Effect of wave spectral variability on stochastic response of a long-span bridge subjected to random waves during tropical cyclones[J]. Journal of Bridge Engineering, 2020, 25(1): 04019131 doi: 10.1061/(ASCE)BE.1943-5592.0001517 [8] Li Gang, Jiang Yunmu, Yu Dinghao, et al. A mixed stochastic waves model for analyzing offshore structures considering engineering characteristics correlation of wind-generated-wave and swell[J]. Ocean Engineering, 2024, 314: 119671. doi: 10.1016/j.oceaneng.2024.119671 [9] Han Xinyu, Jiang Yunpeng, Dong Sheng. Wave forces on crown wall of rubble mound breakwater under swell waves[J]. Ocean Engineering, 2022, 259: 111911. doi: 10.1016/j.oceaneng.2022.111911 [10] Van Gent M R A. Influence of oblique wave attack on wave overtopping at caisson breakwaters with sea and swell conditions[J]. Coastal Engineering, 2021, 164: 103834. doi: 10.1016/j.coastaleng.2020.103834 [11] Radfar S, Shafieefar M, Akbari H, et al. Design of a rubble mound breakwater under the combined effect of wave heights and water levels, under present and future climate conditions[J]. Applied Ocean Research, 2021, 112: 102711. doi: 10.1016/j.apor.2021.102711 [12] Van Der Werf I M, Van Gent M R A. Wave overtopping over coastal structures with oblique wind and swell waves[J]. Journal of Marine Science and Engineering, 2018, 6(4): 149. doi: 10.3390/jmse6040149 [13] Giske F I G, Leira B J, Øiseth O. Full long-term extreme response analysis of marine structures using inverse FORM[J]. Probabilistic Engineering Mechanics, 2017, 50: 1−8. doi: 10.1016/j.probengmech.2017.10.007 [14] Low Y M, Huang Xiaoxu. Long-term extreme response analysis of offshore structures by combining importance sampling with subset simulation[J]. Structural Safety, 2017, 69: 79−95. doi: 10.1016/j.strusafe.2017.08.001 [15] Giske F I G, Kvåle K A, Leira B J, et al. Long-term extreme response analysis of a long-span pontoon bridge[J]. Marine Structures, 2018, 58: 154−171. doi: 10.1016/j.marstruc.2017.11.010 [16] Li Xuan, Zhang Wei. Long-term assessment of a floating offshore wind turbine under environmental conditions with multivariate dependence structures[J]. Renewable Energy, 2020, 147: 764−775. doi: 10.1016/j.renene.2019.09.076 [17] Haver S, Winterstein S R. Environmental contour lines: a method for estimating long term extremes by a short term analysis[C]//Paper presented at the SNAME Maritime Convention. Houston: SNAME, 2008: D011S002R005. [18] Agarwal P, Manuel L. Simulation of offshore wind turbine response for long-term extreme load prediction[J]. Engineering Structures, 2009, 31(10): 2236−2246. doi: 10.1016/j.engstruct.2009.04.002 [19] Winterstein S R, Ude T C, Cornell C A, et al. Environmental parameters for extreme response: inverse FORM with omission factors[C]//Proceedings of the 6th International Conference on Structural Safety and Reliability. Innsbruck: International Association for Structural Safety and Reliability, 1993: 551−557. [20] Karimirad M, Moan T. Extreme dynamic structural response analysis of catenary moored spar wind turbine in harsh environmental conditions[J]. Journal of Offshore Mechanics and Arctic Engineering, 2011, 133(4): 041103. doi: 10.1115/1.4003393 [21] Rony J S, Karmakar D. Long-term response analysis of hybrid STLP-WEC offshore floating wind turbine[J]. Ships and Offshore Structures, 2025. [22] Manuel L, Nguyen P T T, Canning J, et al. Alternative approaches to develop environmental contours from metocean data[J]. Journal of Ocean Engineering and Marine Energy, 2018, 4(4): 293−310. doi: 10.1007/s40722-018-0123-0 [23] Öhlschläger Y. Exploring the feasibility of placing a wind turbine on top of an FPSO[D]. Delft: Delft University of Technology, 2022. [24] Wang Xiaozhi, Pegg N. Proceedings of the 21st international ship and offshore structures congress VOLUME 3 discussions revision 1[C]//21st International Ship and Offshore Structures Congress Volume 3 Discussions. Vancouver, Canada: SNAME, 2022. [25] Chen Lingte. Integrated energy operation solution customized for floating offshore wind power characteristics[D]. Glasgow: University of Glasgow, 2024. [26] IEC. IEC 61400-3, Wind turbines-Part 3: design requirements for offshore wind turbines[S]. International Electrotechnical Commission, 2009. [27] IEC. IEC 61400-2, Wind turbines-Part 2: design requirements for small wind turbines[S]. International Electrotechnical Commission, 2013. [28] DNV. DNV-RP-C205, Environmental conditions and environmental loads[S]. Det Norske Veritas, 2017. [29] 中华人民共和国住房和城乡建设部. 城市绿地规划标准: GB/T 51346−2019[S]. 北京: 中国建筑工业出版社, 2019.Ministry of Housing and Urban Rural Development of the People’s Republic of China. Standard for planning of urban green space: GB/T 51346-2019[S]. Beijing: China Architecture & Building Press, 2019. [30] Hersbach H, Bell B, Berrisford P, et al. The ERA5 global reanalysis[J]. Quarterly Journal of the Royal Meteorological Society, 2020, 146(730): 1999−2049. doi: 10.1002/qj.3803 [31] Hersbach H, Bell B, Berrisford P, et al. The ERA5 Global Reanalysis: achieving a detailed record of the climate and weather for the past 70 years[C]//Proceedings of the 22nd EGU General Assembly. EGU, 2020: 10375. [32] Wang Jichao, Wang Yue. Evaluation of the ERA5 significant wave height against NDBC buoy data from 1979 to 2019[J]. Marine Geodesy, 2022, 45(2): 151−165. doi: 10.1080/01490419.2021.2011502 [33] Çalışır E, Soran M B, Akpınar A. Quality of the ERA5 and CFSR winds and their contribution to wave modelling performance in a semi-closed sea[J]. Journal of Operational Oceanography, 2023, 16(2): 106−130. doi: 10.1080/1755876X.2021.1911126 [34] Wright E E, Bourassa M A, Stoffelen A, et al. Characterizing buoy wind speed error in high winds and varying sea state with ASCAT and ERA5[J]. Remote Sensing, 2021, 13(22): 4558. doi: 10.3390/rs13224558 [35] Chen Y C. A tutorial on kernel density estimation and recent advances[J]. Biostatistics & Epidemiology, 2017, 1(1): 161−187. [36] Joe H. Families of m-variate distributions with given margins and m(m-1)/2 bivariate dependence parameters[J]. Lecture Notes-Monograph Series, 1996, 28: 120−141. [37] Dißmann J, Brechmann E C, Czado C, et al. Selecting and estimating regular vine copulae and application to financial returns[J]. Computational Statistics & Data Analysis, 2013, 59: 52−69. [38] Kendall M G. A new measure of rank correlation[J]. Biometrika, 1938, 30(1/2): 81−93. doi: 10.2307/2332226 [39] Pearson K. Notes on the history of correlation[J]. Biometrika, 1920, 13(1): 25−45. doi: 10.1093/biomet/13.1.25 [40] Diks C, Panchenko V. A new statistic and practical guidelines for nonparametric Granger causality testing[J]. Journal of Economic Dynamics and Control, 2006, 30(9/10): 1647−1669. [41] Barnett L, Seth A K. The MVGC multivariate Granger causality toolbox: a new approach to Granger-causal inference[J]. Journal of Neuroscience Methods, 2014, 223: 50−68. doi: 10.1016/j.jneumeth.2013.10.018 -
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