Numerical Modelling and Global Response Assessment of Floating Docks towards Efficient, Safer and Autonomous Docking Operations

• Main Author: Zhang, Jianan
• Other Authors: Ong, Muk Chen, Li, Lin, Wen, Xueliang
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: University of Stavanger, Norway 2024
• Subjects: offshore teknologi; floating decks; VDP::Teknologi: 500; Arctic
• Online Access: https://hdl.handle.net/11250/3129951

PhD thesis in Offshore technology Floating docks are known for their construction efficiency and operational flexibility compared to traditional graving docks. They play an important role in shipyards by serving as essential platforms for vessel construction, maintenance, and repair. Docking a vessel relies on precise ballasting and de-ballasting operations for achieving the desired floating position of the floating dock. Traditionally, these tasks are manually performed by skilled dock masters who regulate ballast valves and pumps. The entire vessel-docking operation takes hours, and the motions of the floating dock and vessel are slowly and steadily. However, the floating dock and vessel are still facing safety challenges during operations. According to the reported accidents occurring in floating dock operations, malfunctions of the ballast water system, overloading and improper ballast control are the main threats to the stability and structural integrity of the floating docks. To address these concerns and enhance operational safety, a thorough response assessment of vessel-docking operations is important. This thesis focuses on developing an in-house code to facilitate a comprehensive global response assessment of a full-scale floating dock, aiming to enhance overall operational safety and efficiency. The in-house code is developed under a quasi-static assumption and enables dynamic, stability and global structural response assessments of various types of floating dock operations. Multiple numerical tools are incorporated into this code. Various loads applied to the floating dock and vessel are determined using the numerical tools: a hydrostatic force model, a hydrodynamic force model, a mooring force model, and a contact force model. Within the load calculations, the dock-vessel coupling loads are highlighted, including contact loads between the docking blocks and the docked vessel and the loads attributed to the mooring ropes between the dock and vessel. A six-degree-of-freedom (6-DOF) model is ...