系统模拟海上风电典型地质条件下矩形桩靴基础的贯入过程。研究基于模拟结果,提取发生塑性应变的基础土体范围确定土体软化区域并计算相应的土体强度折减系数。在此基础上构建小变形有限元模型,计算各向刚度折减系数η并与不考虑土体软化的相同模型进行对比探究土体软化效应对桩靴在位刚度的影响。此外,针对剪切刚度系数Gmax/su和破坏剪应变γfp等刚度参数开展系统化参数分析。结果表明：土体软化效应对桩靴各向在位刚度均有不同程度的影响且不可忽视,桩靴基础的各向刚度折减系数均随荷载的增大而减小,变化趋势基本保持一致,各向刚度折减系数随Gmax/su的增大而减小,随γfp的增大而增大。
Abstract
Adopting the CEL finite element method to systematically simulate the penetration process of rectangular spudcan foundations under typical offshore wind geological conditions. Based on simulation results, the extent of plastically strained soil around the foundation is quantified, soil softening zones are identified, and corresponding strength reduction factors are calculated. Subsequently, small-strain finite element model incorporating these softening parameters are developed to calculate directional stiffness reduction coefficient η. Comparative analyses with non-softening reference models reveal the substantial influence of soil strength degradation on foundation stiffness. A comprehensive parametric study further evaluates the sensitivity of stiffness characteristics to two critical geotechnical parameters： the normalized shear stiffness ratio Gmax/su and the critical shear strain at failure γfp. Results demonstrate that：1） Soil softening effects varies with different directional in-situ stiffness components, but the extent cannot be neglected; 2） Stiffness reduction coefficients exhibits consistent decreasing trend with increasing level of loading;3） Stiffness increases with higher Gmax/su, but decrease with larger γfp.
关键词
海上风电 /
数值模拟 /
刚度矩阵 /
桩靴基础 /
安装效应 /
NGI-ADP本构模型
Key words
offshore wind power /
numerical simulation /
stiffness matrix /
spudcan foundation /
installation effect /
NGI-ADP constitutive model
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基金
企事业委托项目（CG-2024-K-012）; 国家自然科学基金（42177122）; 青年泰山学者项目（tsqn202211071)
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