Boskalis subsidiary Dockwise is the global market leader in heavy marine transport. Their fleet of over 20 semi-Submersible Heavy Transport Vessels (SHTV) is capable to carry the heaviest and largest structures. Until today the load or discharge operation of a floating body has o
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Boskalis subsidiary Dockwise is the global market leader in heavy marine transport. Their fleet of over 20 semi-Submersible Heavy Transport Vessels (SHTV) is capable to carry the heaviest and largest structures. Until today the load or discharge operation of a floating body has only been performed in sheltered waters. Here, the influences of the environmental loading (wind, waves and current) are limited. Floating Production Storage and Offloading vessels (FPSO) are subjected to hull maintenance and repairs in the near future, which causes a major downtime due to transportation. If the maintenance of FPSOs could be performed offshore, it could reduce this downtime significantly. Due to the environmental loading the SHTV and FPSO move separately. In order to perform a safe offshore load/discharge operation their relative motion should be within the width of the cribbing. The aim of this thesis is to analyse the influence of the location of the connections between the two vessels on the relative transverse motion at keel level of the FPSO. Sway, roll and yaw are considered as the main degrees of freedom (DOF) that have influence on the transverse motion. A numerical model is built to solve the equations of motion in the frequency domain for a 3DOF system. This system consists of a rigid body which represents the FPSO. The rigid body is connected to a set of springs and dashpots which influence its behaviour. For every combination of location and parameters of the spring/dashpot system the numerical model calculates the response. The outcome of all these runs are brought together in contour graphs that give insight to a possible optimal location for the connections and their corresponding parameters. It is found possible to get the transverse motions at keel level within the limits of the cribbing. By positioning the spring/dashpot systems in the corresponding optimal location the minimum required stiffness can be reduced. A fraction of the critical damping at each spring location appears to be adequate in reducing the motions during resonance. The significant forces in both spring/dashpot locations are very high but workable.