Table 1_RAO-driven dynamic assessment of a subsea-manifold installation at 1526 m water depth.docx

This study develops an RAO-driven one-way coupled time-domain assessment of the Normand Oceanic crane-wire-rigging-Manifold E3 system in OrcaFlex. Vessel and crane-tip motions are prescribed from displacement response-amplitude operators, while the nonlinear hoisting lines, rigging, and six-degree-of-freedom payload respond dynamically without feedback to the vessel solution.

The analysis covers six installation stages from half-submerged entry to a controlled approach 10 m above the seabed at 1526 m water depth. Stage-specific calculations quantify crane-tip, hook, and sling forces, dynamic amplification, natural-period migration, and approach velocity for spectral peak periods of 4–11 s and three project headings. The hydrodynamic formulation distinguishes the 43.51 t displaced-water reference mass from the 1874.90 t vertical added mass used in the dynamic model.