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CHAPTER 6. SEDIMENT TRANSPORT MODELS
The investigator must limit modeling attempts to situations in which
the sediment transport is dominated by a single mode of transport. Only then can the model be scaled to produce reasonable, quantitative results.
For many modeling efforts, a very important step is to get good quality
prototype data. This step is essential if the model scaling relationships
require calibration. Prototype data are needed to verify the movable-bed
model, and the model is considered verified if it reproduces the evolution of
all bottom features as observed in the prototype. A common belief among
those who conduct movable-bed modeling studies is
A verified model can be used with confidence to predict
future evolution due to coastal modifications provided
the mode of sediment transport is much the same as it
was in the verification.
“This is a simple and reliable rule, although no rigorous justification has
ever been made” (Le Méhauté 1976).
6.1.4 Cautions About Movable-Bed Models
Throughout the introduction to this chapter, cautions have been made
about the need to be careful when dealing with movable-bed scale models
and their results. These cautions have been offered by accomplished modelers who have had years of experience, so please don’t take these cautions
lightly. In closing, here are two additional bits of wisdom which express the
positive and negative aspects of movable-bed physical modeling.
Movable-bed models of the coastal zone should be used with discretion. While they can provide valuable insight into the complicated interaction of coastal processes, they can also lead to
catastrophic consequences due to over confident interpretation.
(Noda 1972).
With all the limitations which they may present, coastal movablebed models constitute valuable instruments to predict the effects
of mantime structures on adjacent beds. (Motta 1986).
6.2 Movable-Bed Scaling Requirements
A generalized coastal movable-bed model would be able to model correctly
the complex interaction of short waves, long waves, unidirectional flows,
CHAPTER 6. SEDIMENT TRANSPORT MODELS
The investigator must limit modeling attempts to situations in which
the sediment transport is dominated by a single mode of transport. Only then can the model be scaled to produce reasonable, quantitative results.
For many modeling efforts, a very important step is to get good quality
prototype data. This step is essential if the model scaling relationships
require calibration. Prototype data are needed to verify the movable-bed
model, and the model is considered verified if it reproduces the evolution of
all bottom features as observed in the prototype. A common belief among
those who conduct movable-bed modeling studies is
A verified model can be used with confidence to predict
future evolution due to coastal modifications provided
the mode of sediment transport is much the same as it
was in the verification.
“This is a simple and reliable rule, although no rigorous justification has
ever been made” (Le Méhauté 1976).
6.1.4 Cautions About Movable-Bed Models
Throughout the introduction to this chapter, cautions have been made
about the need to be careful when dealing with movable-bed scale models
and their results. These cautions have been offered by accomplished modelers who have had years of experience, so please don’t take these cautions
lightly. In closing, here are two additional bits of wisdom which express the
positive and negative aspects of movable-bed physical modeling.
Movable-bed models of the coastal zone should be used with discretion. While they can provide valuable insight into the complicated interaction of coastal processes, they can also lead to
catastrophic consequences due to over confident interpretation.
(Noda 1972).
With all the limitations which they may present, coastal movablebed models constitute valuable instruments to predict the effects
of mantime structures on adjacent beds. (Motta 1986).
6.2 Movable-Bed Scaling Requirements
A generalized coastal movable-bed model would be able to model correctly
the complex interaction of short waves, long waves, unidirectional flows,