For ships and floating structures, the static and dynamic loads originate from pressures and accelerations occurring due to the static draft and dynamic motions of the vessel in a sea state.

The dynamic loads are selected from statistical processing of hydrodynamic analysis results to maximize a range of load parameters such as global shear and bending, wave pressures, internal pressure, accelerations, and then applied to the finite element model. The loads are derived from a number of sources including:

  • Loading conditions of the vessel:

    • Lightship weight distribution
    • Placement of heavier items such as engines and equipment
    • Tank Fillings
    • Model check that mass and centers of gravity match
  • Dynamic loads acting on the vessel

    • Calculated by rules, frequency or time domain programs
    • Selected to maximize a dynamic load parameters (DLP)
    • Peaks selected in combination with static loads
    • Global shear forces and moments (longitudinal, transverse, torsion)
    • Accelerations at selected locations
    • Inclinations to capture gravity effects

  • Balancing of Loads

    • Position change in the sea or inertia accelerations
    • Required to minimize boundary condition reactions

 

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