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CHAPTER 5. COASTAL STRUCTURE MODELS
rubble-mound structure models. For randomly-place armor layers, model
technicians must resist the natural tendency to pack the armor units in a
matrix that is tighter than possible in prototype construction. Building a
rubble-mound structure model too tightly could result in a design that will
not withstand expected prototype wave and water-level conditions.
Owen and Briggs (1985) discussed many of the practical aspects of managing a physical model study for a client, and they listed several pertinent
factors that are interwoven with the technical side of physical modeling.
One of the important points they made was that the cost of physical modeling is significant; but in relation to cost savings in construction or maintenance, modeling costs are usually justified.
Finally, guidelines for modeling forces on cylinders and pile-type structures were not discussed in this chapter. These topics have been extensively
studied by the offshore industry, and suitable references are available.