DELIVERABLES

OFFSHORE MOORING ANALYSIS

The moored performance of various configurations and/or assets can be numerically assessed. Compliance to design standards is reported for marine warranty surveying before operations are planned, or when feasibility of new concepts are to be evaluated. This is done in the following steps:

• Identification of design vessel characteristics, including design loading conditions, winch/fairlead location and eccentric manifold positions (if applicable).
• Identification of the mooring configuration type: catenary, taut, side-by-side, tandem or a combination.
• Evaluation of the static mooring configuration. This is done to evaluate the static equilibrium position (including any offsets) as starting point for a dynamic assessment. For weathervaning systems, static offsets due to non-collinear wind, waves and currents can be reported as well (e.g. heading analysis).
• A dynamic numerical mooring assessment can be performed to calculate responses for the following use cases in intact and damaged mooring line scenarios:
  • Calculating design values of e.g. manifold envelopes and vessel offsets; ship based infrastructure (lines, winch loads) and other parameters (anchor loads, uplift, bending/compression). Usually, the external loading is linked to a return period.
  • Evaluate mooring safety by performing operability,downtime and/or persistency analysis by comparing responses to limiting criteria and combining results with long term statistics.