Understanding the complex dynamic interaction during the dredging operation using a Cutter Suction Dredger can improve the production. Some of the parts of the CSD are the dredge hull, spud and the cutter shaft. The dredge hull is analysed for the ocean wave by the scaled down model to determine the motions in all six directions. By understanding the effect of the dredge hull over the spud, the spud is designed to the scaled down model and analysed for the motions due to the dredge hull as an input. The transient analysis of the spud-soil system has been done for the time variant water waves based on Morison equation below the water surface length of the spud. The transmission shaft is analysed for the modal characteristics which consists of two inclined shaft coupled using universal joints. A finite element model of the transmission shaft is developed. The shafts were modelled as a Eider-Bernoulli beam with five degrees of freedom per node and the universal joint were modelled as spring elements. The eigenvalue problem was analysed to determine the natural frequency and mode shapes for a straight and shafts inclined at a specific configuration. External excitation in the form of wave loading was calculated based on Morison equation. Considering the culler motion at the sea bed as an impulse to the free end the temporal response due to these excitations were calculated. A parametric study was carried out to understand the influence on the natural frequency and mode shapes by varying the spring stiffness and damping of universal joint. With the different spring stiffness at the joint the natural frequency and mode shapes along with the time response were determined. The mode shape and temporal response showed sensitivity1 to change in damping and stiffness of the universal joint. Therefore, by careful tuning of the stiffness and damping of the universal joint the vibration transmission along the length of the shaft can be controlled.
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