Session: 10-05-01: Bucket Foundations and Caissons

Submission Number: 155322

Evaluation of Anchoring Capacity of Suction Anchors With Fins in Silt 

Anchoring systems are essential in ocean engineering, stabilizing offshore structures against forces like currents, wind, and waves. Key types include drag anchors, piles, suction anchors, and torpedo anchors. Each type is designed to meet specific engineering needs, providing different load-bearing capabilities and installation methods suitable for diverse marine environments. Among these, suction anchors are favored for their numerous advantages, such as the excellent vertical load-bearing capacity (in contrast with drag anchors), low-noise installation (in contrast with driven piles), and highly precise installation positioning (in contrast with torpedo anchors). Conventional suction anchors’ structural stability and load-bearing capacity can be enhanced by fin.  Fins in suction anchors lead to improved load-bearing capacity and anti-rotation performance specifically. In this study, the model of suction anchor is built by using the finite element technique with the commercial software PLAXIS 3D. The suction anchor model is first validated with the centrifuge test data from the literature, demonstrating good agreement between the experimental data and the numerical results. Next, this study evaluates the effects of fin direction on bearing capacity. It was found that regardless of the width of the fins, the maximum bearing capacity occurs when the fins are perpendicular to the direction of the applied force. The bearing capacity of suction anchors with fins is also assessed under different inclination angles. Numerical experiments indicate that varying inclination angles, which may result from different mooring types, have a greater effect on the capacity of finned suction anchors compared to conventional suction anchors. Furthermore, this study identifies the optimal fin dimension, both width and length. This factor is crucial in optimizing the cost regarding the material usage. Ultimately, a simplified formula will be provided for quickly assessing the maximum bearing capacity of finned suction anchors under horizontal loading conditions, aiding in the rapid evaluation of their performance in horizontal load scenarios. This study offers researchers and industry professionals a reference for making informed decisions on the adoption of fin designs.

Presenting Author: YI-HSIU LIU Department of Engineering Science and Ocean Engineering, National Taiwan University

Presenting Author Biography: I am Yi-Hsiu Liu from Taiwan. I'm a master's student at the Department of Engineering Science and Ocean Engineering, National Taiwan University. I'm interest is in anchoring systems for floating offshore wind turbines.