3 October 2005
Ship waves may be important in some cases. The response of a moored
vessel to wave forcing includes:
a) A steady mean force.
b) First order response, where the vessel responds to each wave, and
c) Second order response, where some natural long period mode of
ship/mooring motion, which usually has little damping, is forced by the group or other
nature of the waves.
If any of these effects are important to a given mooring design, then a six-
degree-of-freedom dynamic of the system generally needs to be considered in design.
Some guidance on safe wave limits for moored manned small craft is given in Table 3-
Water Depths. The bathymetry of a site may be complex, depending on
the geology and history of dredging. Water depth may also be a function of time, if
there is shoaling or scouring. Water depths are highly site specific, so hydrographic
surveys of the project site are recommended.
Environmental Design Information. Some sources of environmental
design information of interest to mooring designers are summarized in Table 3-15.