辐射沙洲海域海上风电基础自然冲刷风险定量评估与应用

Quantitative assessment and application of natural scour risk for offshore wind turbine pile foundations in a sea area with radiated sandbars

中文关键词:  滩槽演变  海洋工程  自然冲刷  风险评估

英文关键词:beach-trough evolution  offshore engineering  natural scour  risk assessment

中文摘要:

      辐射沙洲海域的海上风机桩基稳定性，因强潮汐、多向流、滩槽交错及高泥沙活动性等复杂水沙动力条件面临严峻挑战，而现有评估方法往往难以定量捕捉自然演变产生的冲刷风险。为此，本文提出一种 “动力条件-泥沙活动性-冲淤速率”耦合的桩基冲刷风险评估框架，划分 各场区风险等级。该方法综合利用实测地形、水文泥沙观测数据与数值模型模拟结果，计算各区域起动流速与起动波高，判定泥沙活动性，并结合多时段海床冲淤变化，建立定量化风险等级指标。应用于江苏亮月沙海域某风电项目后，成功识别出不同风险区域，为风机机位优化及桩基设计提供了明确的防护冲刷深度。该框架克服了单因素评估与经验方法的局限性，为复杂动力海洋环境下的桩基风险评估提供了稳健且可推广的工具。

英文摘要:

      The stability of offshore wind turbine pile foundations in radiating sandbank regions faces significant challenges due to complex hydro-sediment dynamics, including strong tides, multidirectional currents, alternating shoals and troughs, and high sediment mobility. Existing assessment methods often struggle to capture the scour risks arising from natural seabed evolution. To address this issue, this study proposes a three-dimensional coupled assessment framework of "hydrodynamic conditions–sediment mobility–erosion/deposition rate" to classify pile foundation scour risk levels across different zones. The method integrates measured bathymetry, hydrodynamic and sediment data with numerical model results to calculate critical shear velocities and wave heights, determine sediment mobility, and, in combination with multi-period seabed morphological changes, establish a quantitative risk grading index. When applied to an offshore wind farm project in the Liangyuesha area of Jiangsu Province, the framework successfully identified spatial variations in scour risk and provided clear protective scour depth recommendations for turbine layout optimization and foundation design. This approach overcomes the limitations of single-factor and empirical evaluation methods, offering a robust and transferable tool for pile foundation risk assessment in complex marine environments.