基于欧拉–拉格朗日耦合方法分析吸力锚力学沉贯特性

Analysis of the Mechanical Penetration Characteristics of Suction Anchors Based on the Euler-Lagrange Coupling Method

摘要: 吸力锚结构被广泛应用于海洋建筑结构的基础中，其贯入施工过程呈现为大变形的特点，力学特性极其复杂。欧拉–拉格朗日耦合方法综合了拉格朗日方法的高效性和准确性以及欧拉方法中网格和材料相互独立等优点，为此，采用欧拉–拉格朗日耦合方法开展吸力锚成层土贯入施工力学特性模拟。结果表明：可将土塞隆起过程分为三个阶段，分别为隆起增长期、隆起过渡期以及隆起平缓期；在沉贯过程中产生的应力应变主要集中在吸力锚端部附近土体中，且随着贯入深度的增加逐渐增大，竖向应力会在锚端部附近的土体中形成应力拱，限制土塞高度的增长；与外壁侧摩阻力和端部阻力相比，土塞效应对内壁侧阻力的影响程度更大，同时土塞效应会使端部阻力有所减小。欧拉–拉格朗日耦合方法能够很好地模拟吸力锚沉贯过程，为深海吸力锚的施工安装提供了一种可靠、有效的模拟方法。

Abstract: Suction anchor structures are widely used as foundations in marine construction, and the penetration construction process exhibits characteristics of large deformation, making its mechanical properties extremely complex. The Euler-Lagrange coupling method combines the efficiency and accuracy of the Lagrangian method with the advantage of independence between the grid and material in the Eulerian method. Therefore, the Euler-Lagrange coupling method is used to simulate the mechanical characteristics of suction anchor penetration into layered soil during construction. The results show that the soil plug uplift process can be divided into three stages: the uplift growth stage, the uplift transition stage, and the uplift stabilization stage. The stress and strain generated during the penetration process are mainly concentrated in the soil near the tip of the suction anchor and gradually increase with penetration depth. Vertical stress forms a stress arch in the soil near the anchor tip, limiting the growth of the soil plug height. Compared with the external wall side friction and tip resistance, the soil plug effect has a greater impact on the internal wall side resistance, and the soil plug effect also reduces the tip resistance. The Euler-Lagrange coupling method can effectively simulate the suction anchor penetration process, providing a reliable and effective simulation method for the construction and installation of deep-sea suction anchors.