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Coastal Engineering: Theory and Practice
The following enlisted are the typical reasons for adopting model
studies
• When the known and available analytical methods are insufficient to solve
a given problem
• To détermine the empirical co-efficient for known équations
• To validate or substantiate the results of a newly introduced analytical
tool
• To investigate failure pattern and mechanism.
The terminologies often used in model analysis and their définitions are
given below.
Prototype is defined as the actual System or a field problem being investigated.
Model is defined as the substitute System that is proportional to the
prototype by a scale ratio.
Homologous is defined as the corresponding conditions in the model and
its prototype.
9.3.2 Complété similarity
The priority of most of the model studies is to achieve a simple numerical
value such as the destructive or ultimate load. These numerical values are
dépendent on the variables involved. In order to get accurate results through
dimensional analysis the variables are grouped to form a complété set of
dimensionless products such as 7ir, tt2, ..., 7rn. If the independent variables
7Fi,7T2,..., 7rn possess the same value for the model and the prototype then
the model is said to be completely similar. Complété similarity is nearly
impossible to achieve in our model studies. It is to be noted that the forces
such as surface tension, surface roughness etc., may influence the model
but not the prototype and the independent dimensionless variables which
are believed to hâve secondary influences are to be neglected. Scale effects
(discussed later in this chapter) of the same magnitude occurs inevitably
in ail models. To avoid scale effects larger models are to be employed.
9.3.3 Applications of model analysis
Most of the marine structures such as breakwaters, jetties, groins, training walls, seawalls, piers, intake and outfall structures, etc. can be tested,
for their interaction with waves as well as their effect on the coast. The
behaviour and the stability of Coastal structures could be verified in the
Coastal Engineering: Theory and Practice
The following enlisted are the typical reasons for adopting model
studies
• When the known and available analytical methods are insufficient to solve
a given problem
• To détermine the empirical co-efficient for known équations
• To validate or substantiate the results of a newly introduced analytical
tool
• To investigate failure pattern and mechanism.
The terminologies often used in model analysis and their définitions are
given below.
Prototype is defined as the actual System or a field problem being investigated.
Model is defined as the substitute System that is proportional to the
prototype by a scale ratio.
Homologous is defined as the corresponding conditions in the model and
its prototype.
9.3.2 Complété similarity
The priority of most of the model studies is to achieve a simple numerical
value such as the destructive or ultimate load. These numerical values are
dépendent on the variables involved. In order to get accurate results through
dimensional analysis the variables are grouped to form a complété set of
dimensionless products such as 7ir, tt2, ..., 7rn. If the independent variables
7Fi,7T2,..., 7rn possess the same value for the model and the prototype then
the model is said to be completely similar. Complété similarity is nearly
impossible to achieve in our model studies. It is to be noted that the forces
such as surface tension, surface roughness etc., may influence the model
but not the prototype and the independent dimensionless variables which
are believed to hâve secondary influences are to be neglected. Scale effects
(discussed later in this chapter) of the same magnitude occurs inevitably
in ail models. To avoid scale effects larger models are to be employed.
9.3.3 Applications of model analysis
Most of the marine structures such as breakwaters, jetties, groins, training walls, seawalls, piers, intake and outfall structures, etc. can be tested,
for their interaction with waves as well as their effect on the coast. The
behaviour and the stability of Coastal structures could be verified in the