A Modernized Safety Concept for Ship Force Evaluations During Lock Filling Processes

Abstract

AbstractA ship in a lock chamber is exposed to forces acting on the hull during the filling and emptying processes. These forces accelerate the ship and lead to a displacement. To avoid a collision of the ship with the lock structure, it is moored with mooring lines, which can be strained up to a certain breaking load. The force acting in the mooring lines is called the mooring line force and must be distinguished from the ship force. If the mooring line force exceeds the breaking load, the mooring line will fail and the tension energy will abruptly be transformed into kinetic energy. A snap-back of the mooring line ends can produce great forces and the mooring staff is at risk for major injuries. Furthermore, the ship will start to move and could damage the structure and itself. Thus, the mooring line force must be limited during the locking process. The mooring line force depends on the ship force and, furthermore, on the properties of ship and mooring lines. Due to the number of possible parameter combinations the given ship force alone might not be sufficient to judge on the mooring line safety. In this paper a statistical approach to determine the relations between mooring line configuration, mooring line forces and ship force based on Monte Carlo simulations is shown.