As vessels become larger and competition between ports intensifies, there has been an increase in the number of cases where vessels that exceed the available berths are berthed at the pier. Therefore, there has been an increase in the number of cases in which the bow or stern of a ship is projected and moored. The risk of overhanging berthing is that mooring safety can be compromised because it is not possible to connect the bow and stern mooring line to the ship properly. In addition, collision accidents may occur between moving vessels if the view of a vessel moving in the port is obstructed. Therefore, in this study, the simulation of mooring safety was performed according to the overhanging range in Piers No. 6 and 7 in Ulsan’s main port to propose the overhanging limit and operational standards according to each ship. As a result of the assessment, 30,000 DWT bulkers are able to overhang up to 0.75B, and 50,000 DWT bulkers can overhang up to 0.50B. The results of this study are expected to be used as basic data for setting the allowable overhang limit, as well as clear usage criteria for safe unloading operations.

Abstract
 1. Introduction
 2. Selection of target pier for simulation
  2.1 Selection of target pier
  2.2 Analysis of the port entrance of the target pier
 3. Simulation for overhanging berthing
  3.1 Target ship Selection
  3.2 Modeling of mooring conditions
  3.3 Modeling of environmental external force
  3.4 Evaluation factors for simulation
 4. The results of evaluation on a 30,000 DWT bulker
  4.1 Tension of the mooring line
  4.2 Load of the bollard
  4.3 Reaction force of the fender
  4.4 Ship's motion in 6-DOF
  4.5 Overall results
 5. The results of evaluation on a 50,000 DWT bulker
  5.1 Tension of the mooring line
  5.2 Load of the bollard
  5.3 Reaction force of the fender
  5.4 Ship's motion in 6-DOF
  5.5 Overall results
 6. Conclusion
 References

• Seungyeon Kim(Division of Navigation Science, Mokpo National Maritime University)
• Yongung Yu(Graduate school of Korea Maritime and Ocean University)
• Yunsok Lee(Division of Ship Navigation, Korea Maritime and Ocean University) Corresponding Author