随着近海风机大型化快速发展，具有承载转化提升、施工工期缩短、建设成本可控等优势的复杂桩基础受到越来越多关注和应用。已有规范和经验多是基于大直径单桩基础，对于三脚架、导管架等新型复杂桩基础与水动力泥沙相互作用机理及其冲刷防护技术方法仍缺少系统认知和科学指导，亟需开展深入研究。本项目依托山东典型近海风电场工程，采用现场原型观测、物理模型试验和数值模拟分析相结合的手段，研究复杂桩基础在波流共同作用和高浓度泥沙环境中的土体弱化-冲刷耦合机理，阐明复杂桩基础在动床冲刷过程中自振频率降低、桩体变形累积、承载力退化等结构力学性能弱化特性；建立多尺度耦合的水动力-结构物-海床响应-泥沙运动-地貌演变三维数学模型，揭示复杂桩基群对邻近海域水沙运动和海岸冲淤演变的影响机制，提出复杂桩基础冲刷的创新防护方法，为山东规模化近海风电场的建设提供科技支撑。

Along with the rapid development of large-scale offshore wind turbine, the complex pile foundation with strong bearing capacity, controllable cost and short construction period has become more and more popular. Most existing methods and experience in protecting offshore wind turbine foundations have been established for the large-diameter monopile, but very little knowledge has been obtained for the newly developed complex pile foundations, e.g., tripod foundation and jacket foundation. A comprehensive investigation in this aspect is essential. In this study on the basis of typical offshore wind farm in Shandong, both laboratory experiments and numerical simulation will be conducted to investigate the following important topics: the combined failure mechanism for soil degradation and scour around complex pile foundations under wave-current coexisting and high-concentration environment; the dynamic response of pile structure influenced by seabed scour, including the frequency reduction of self-vibration, accumulative structure deformation and weakening of loading resistance; development of an integrated multi-scale numerical model for nearshore hydrodynamic processes, structure deformation, seabed response, sediment transport and morphological evolution; influences of offshore wind farm on the modifications of large-scale sediment pathway and coastal line evolution. The aim is to provide innovative protection method against scour for the construction of large-scale offshore wind farms at Shandong.