基于多尺度有限元的海上升压站脚靴式桩套筒连接结构分析研究

脚靴式海上升压站导管架的桩套筒与主导管的连接结构是关键荷载传递部位。整体梁系有限元模型无法反应局部板型结构的失效状态；截断板系有限元模型则受制于边界条件的合理性，结果不够精确。文中基于某工程海上升压站，建立不同精细化范围的多尺度有限元模型及不同边界条件的截断模型，对结构屈服失效及屈曲失效复核的同时论证了局部网格对计算精细程度的影响及截断模型对边界条件的敏感性；此外，研究了轭板板厚及应力比对屈曲失效的敏感程度，为今后海上升压站脚靴结构不同阶段的设计、优化提供参考和借鉴。

Research on the pile-sleeve structure of boot-type offshore substation based on multi-scale finite element method

The pile-sleeve structure in the boot-type offshore substation is the key load-transferring part. The overall finite element beam model cannot simulate the failure of the local structure, and the truncated plated finite element may lead to less accurate results due to the rationality of the boundary conditions. Based on a boot-type offshore substation station, we established multi-scale finite element models with different refinement ranges and truncated models with different boundary conditions. And the pile-sleeve structure was checked for both yielding and buckling failure modes. We verified the influences of local mesh on the calculation precision and the sensitivity of the truncated model to the boundary conditions. Furthermore, the sensitivity of yoke plate thickness and stress ratio to buckling failure were studied, which could provide experience and reference for the design and optimization of the pile-sleeve structure at different stages of the offshore substation in the future.