The structural analysis was performed in a multiple-step process based on the approach described in Fredriksson et al.
(2007a). One of the first steps was to determine the environmental loading on the cage due to waves and currents, for which a Morison-equation approach was used (Morison et al., 1950). Once the environmental conditions were calculated, a commercial finite element software package MSC.MARC/Mentat (http://www.mscsoftware.com) was used to for hydrodynamic analysis.