海上风机与养殖网箱融合系统中网箱系泊绳张力与导管架基础结构安全性研究

海洋牧场与海上风电融合发展是现代渔业和清洁能源产业融合发展的典型代表，能够构建“海上粮仓+清洁能源”的新产业模式。本文基于福建漳浦六鳌海上风电场风机导管架构建养殖网箱与海上风机融合系统，运用Aqua-FE?有限元工具探究极端波流条件下不同网箱布设深度、波流入射角、生物附着程度对网箱系泊绳张力的影响；采用海洋工程专用设计软件SACS，计算分析风机导管架结构在波流及网箱系泊绳张力作用下的应力分布，评估养殖网箱系泊绳张力对风机导管架基础结构安全性的影响。结果表明，网箱布设深度的增加能够减少网箱系泊绳最大张力，显著改善网箱风机整体结构受力状态；波流入射角的改变对于网箱风机整体结构安全性影响不大；网衣生物附着程度的增加会显著增加网箱系泊绳最大张力，从而造成风机导管架基础杆件大量失效。综上所述，养殖网箱可布设于适当水深以减少受力，同时应及时清理附着生物，适当增加网箱系泊点附近的导管架杆件和导管架底部桩土点杆件的壁厚，以确保养殖网箱与海上风机融合系统结构安全。该结果可为深入研究网箱与风机融合系统的受力，评估该系统的安全性，优化设计养殖网箱与风机融合系统提供数据支撑。

Study on mooring rope tension and jacket infrastructure safety in integrated system of offshore wind turbine and fish cage

The combination of offshore wind power and aquaculture industry has developed rapidly, which can comprehensively utilize of marine space, maximize the benefits of aquaculture and offshore wind power industry, and realize the simultaneous and efficient output of clean energy and high-quality aquatic products. As one kind of integrated development mode of offshore wind power and cage culture, the fish cage and wind turbine integrated system using the pile foundation of wind turbines to form the fish cage was generally exposed in the extreme sea states with the severe waves and currents. The hydrodynamic of the fish cage and wind turbine integrated system, as well as the evaluation of the structural safety of the pile foundation, are the basis for the construction of the integrated system. It is of great necessity to conduct a more systematic study on the hydrodynamic characteristics of fish cage and offshore wind turbine pile foundations. In this paper, an integrated system of offshore wind turbine and fish cage was constructed based on the wind turbine jacket of offshore wind power in Liu-Ao, Zhang-Pu, Fujian Province. The finite element toolbox, Aqua-FE?, was used to investigate the impacts of different setting depth, wave incidence angle and percentages of bio-fouling on mooring rope tension of fish cage in extreme waves and currents. The relationship between the mooring rope tension at the upper end of the upstream side and the setting depth of fish cage was fitted by nonlinear regression. The effects of waves and currents parameters, as well as mooring line tension of the fish cage, on the stress variations of the wind turbine jacket structure were analyzed by the specialized design software SACS for ocean engineering, and the safety of the wind turbine jacket foundation structure was evaluated. The results show that the increase in the setting depth of the fish cage can reduce the maximum tension of the mooring rope, significantly improving the stress state of the integrated system. The variation of incident angles of wave and current has little effect on the safety of integrated system of offshore wind turbine and fish cage; the rise of the percentage of bio-fouling significantly increases the maximum tension of mooring ropes, resulting in the structural failures of many foundation rods of the wind turbine jacket. As a summary, the fish cage can be arranged in an appropriate water depth to reduce stress. At the same time, the fouling organisms shall be cleaned in time, and the thickness of the jacket rod near the mooring point of the fish cage and the pile-soil point rod at the bottom of the jacket shall be appropriately increased to ensure the structural safety of the integrated system. The results can provide data support for further study of the force of integrated system of offshore wind turbine and fish cage, evaluating the safety of the system, optimizing the integrated structure of fish cage and wind turbine system.