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CHAPTER 5. COASTAL STRUCTURE MODELS
5.6.4
Floating Structure Model Construction
Models of floating coastal structures or vessels can be constructed of the
same materials as the prototype (e.g., floating tire breakwaters), but this
is not a requirement. Regardless of what material is used for model construction, the model must
• Correctly reproduce the exterior geometry of the floating
structure according to the length scale, Nl
• Correctly reproduce the total mass of the structure according to the weight scale (Eqn. 5.55)
• Correctly reproduce mass moments of inertia about the
different axis according to
JV;„ = Nm (NL)2 = N„ (NLf
(5.59)
where Njm is the prototype-to-model scale ratio of mass
moment of inertia, and Nm and Np are the scale ratios of
the total mass and material density, respectively.
5.7 Other Modeling Considerations
Proper design, construction, and operation of a coastal structure physical
model requires sufficient field and design data to: (a) define the problem,
(b) establish the range of environmental conditions, and (c) specify details
of proposed alternatives. Enough information must be available before the
study begins to establish (to the extent possible) the purpose and scope of
the model study. For the types of coastal structures discussed in this chapter, important field and design information includes the following (Hudson,
et al. 1979):
• Shape and size of the structure
• Materials used in construction of the structure
• Shape, size, and density of quarrystone or armor units in
the primary and underlying layers (rubble-mound structures)
• Mass distribution of monolithic or floating structures
• Mooring configurations (floating structures)
• Mooring cable material and elasticity (floating structures)
• Bottom slope seaward of the structure (2-d studies)
CHAPTER 5. COASTAL STRUCTURE MODELS
5.6.4
Floating Structure Model Construction
Models of floating coastal structures or vessels can be constructed of the
same materials as the prototype (e.g., floating tire breakwaters), but this
is not a requirement. Regardless of what material is used for model construction, the model must
• Correctly reproduce the exterior geometry of the floating
structure according to the length scale, Nl
• Correctly reproduce the total mass of the structure according to the weight scale (Eqn. 5.55)
• Correctly reproduce mass moments of inertia about the
different axis according to
JV;„ = Nm (NL)2 = N„ (NLf
(5.59)
where Njm is the prototype-to-model scale ratio of mass
moment of inertia, and Nm and Np are the scale ratios of
the total mass and material density, respectively.
5.7 Other Modeling Considerations
Proper design, construction, and operation of a coastal structure physical
model requires sufficient field and design data to: (a) define the problem,
(b) establish the range of environmental conditions, and (c) specify details
of proposed alternatives. Enough information must be available before the
study begins to establish (to the extent possible) the purpose and scope of
the model study. For the types of coastal structures discussed in this chapter, important field and design information includes the following (Hudson,
et al. 1979):
• Shape and size of the structure
• Materials used in construction of the structure
• Shape, size, and density of quarrystone or armor units in
the primary and underlying layers (rubble-mound structures)
• Mass distribution of monolithic or floating structures
• Mooring configurations (floating structures)
• Mooring cable material and elasticity (floating structures)
• Bottom slope seaward of the structure (2-d studies)