深水养殖网箱浮架变形与破坏机理研究

In China, The deep-water cage aquaculture is an important strategic direction of the mariculture,with significant advantages such as high-capacity culture and high economic benefit. However,the security problem of cage in severe marine conditions has not been fundamentally solved. Many scholars, studying hydrodynamics of net cages, often assuming that the floating collar of cage don’t deform under any conditions.Years of practices had proved that the breakdown of floating collar still happen sometimes, due to serious deformation of which hit by typhoon. There are evidences showing that the destruction probability of larger-scale floating collar is higher. . On the basis of years of hydrodynamics studies of deep-water net cages, this study will use mathematical modeling method combined with physical test and sea in-situ test to carry out the deformation and failure mechanism of floating collar expose to dynamic loads. The main contents include structure deformation of collar under different conditions, collar deformation inherent law, simulation analysis of failure process of collar, evalation of the ultimate bearing capacity of collar expose to marine disaster environment, and safety design parameters of collar. The above studies are aimed to provide scientific reference to the design of floating collar so as to enhance the safety and reliability of deep-water cage aquaculture in severe marine environment.

深水网箱养殖是我国海水设施养殖的重要战略方向，具有养殖容量大、养殖效益好的显著优势，但在高海况下其面临的安全问题却未得到根本解决，国内外众多学者在研究网箱动力学问题时往往忽略浮架的变形。实践证明，台风浪侵袭下网箱浮架因变形严重导致发生弯折破坏现象时有发生，且有证据表明大规格的深水网箱其浮架破坏几率更高。. 本项目拟在多年对深水网箱水动力特性研究的基础上，采用数学建模方法，结合物模试验及海上实测手段，开展动态荷载作用下浮架变形破坏机理研究，系统研究浮架在不同条件下的结构变形，阐明浮架变形差异及内在规律，模拟分析浮架变形破坏过程，评估海洋灾害环境下浮架的极限承载力，获取浮架安全设计参数。通过以上研究，应用上为网箱的浮架设计提供科学依据，提升恶劣海洋环境下深水网箱养殖的安全可靠性。

深水网箱养殖是我国海水设施养殖的重要战略方向，由HDPE材料制作的浮架是深水网箱系统的重要组成部分，在波浪流冲击下具有明显的变形。多年的养殖实践证明，台风浪侵袭下网箱浮架因变形严重导致发生弯折破坏现象时有发生。为保障灾害环境下网箱养殖安全及效益，提升网箱极限承载能力，系统研究海洋环境中网箱浮架的变形破坏机理显得尤为重要。本项目以我国南海区常用的大型HDPE圆形网箱为研究对象，采用数学建模方法，系统构建出深水养殖网箱有限元计算模型，开展了波浪流冲击下深水网箱浮架动力变形的数值模拟研究，确定了浮架最大变形位置，给出了浮架应力、应变及锚绳张力的模拟结果，揭示了不同波况及波流组合海况下的浮架受力变形差异及内在变化规律。基于浮架材料塑性破坏判断条件，评估了海洋灾害环境下网箱浮架的极限承载力，并科学提出了能够有效增强网箱浮架结构安全的技术措施。项目取得的研究成果将对我国深水网箱工程设计与应用具有重要的理论参考价值。