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CHAPTER 5. COASTAL STRUCTURE MODELS
5.1 Introduction to Structure Models
5.1.1 Types of Coastal Structures
The economic design of a stable coastal structure is a difficult problem
involving the complex interaction of waves and structure (Hudson, et al.
1979). For example, waves breaking on a sloping structure involve nonstationary velocity and acceleration fields during runup and rundown. On
rubble-mound structures additional complications arise because these structures are permeable and act as water reservoirs and have high energy absorption capability (Jensen 1989). Optimizing a structure often can only
be achieved by systematic physical model tests.
Coastal structures are intended to protect shorelines or navigation channels from the effects of waves and other hydrodynamic forces. Design must
consider a range of likely wave heights and periods combined with water
level variations composed of tide, storm surge, and wind setup. Some structures are designed to reflect wave energy, while other structures attempt
to decrease most wave energy through wave breaking and dissipation upon
and within a permeable structure.
The most common type of coastal structures are listed below.
• Rubble-Mound Structures. Rubble-mound construction is used extensively for breakwaters, jetties, revetments,
seawalls, and wave absorbers. Rubble-mound structures
have a .. core of quarry-run stones, sand, slag, or other
suitable material (in the case of breakwaters or jetties) protected from wave action by one or more stone underlayers
and a cover layer of relatively large, selected quarry stones
or specially-shaped concrete armor units” (Hudson 1959).
Rubble-mound structures are generally used where water
depths are not cost prohibitive, and a supply of suitable
quarrystone is available. They are also a viable alternative to monolithic structures where the foundation material
lacks the strength necessary to support a monolithic-type
structure. Rubble-mound breakwaters are used extensively
in harbor construction because their porosity minimizes
disturbances caused by wave reflection inside the harbor
(Sharp and Khader 1984). Rubble-mound structures are
widely used throughout the world, so naturally, stability
tests of rubble-mound structures are the most frequently
conducted coastal structure model (Oumeraci 1984).
CHAPTER 5. COASTAL STRUCTURE MODELS
5.1 Introduction to Structure Models
5.1.1 Types of Coastal Structures
The economic design of a stable coastal structure is a difficult problem
involving the complex interaction of waves and structure (Hudson, et al.
1979). For example, waves breaking on a sloping structure involve nonstationary velocity and acceleration fields during runup and rundown. On
rubble-mound structures additional complications arise because these structures are permeable and act as water reservoirs and have high energy absorption capability (Jensen 1989). Optimizing a structure often can only
be achieved by systematic physical model tests.
Coastal structures are intended to protect shorelines or navigation channels from the effects of waves and other hydrodynamic forces. Design must
consider a range of likely wave heights and periods combined with water
level variations composed of tide, storm surge, and wind setup. Some structures are designed to reflect wave energy, while other structures attempt
to decrease most wave energy through wave breaking and dissipation upon
and within a permeable structure.
The most common type of coastal structures are listed below.
• Rubble-Mound Structures. Rubble-mound construction is used extensively for breakwaters, jetties, revetments,
seawalls, and wave absorbers. Rubble-mound structures
have a .. core of quarry-run stones, sand, slag, or other
suitable material (in the case of breakwaters or jetties) protected from wave action by one or more stone underlayers
and a cover layer of relatively large, selected quarry stones
or specially-shaped concrete armor units” (Hudson 1959).
Rubble-mound structures are generally used where water
depths are not cost prohibitive, and a supply of suitable
quarrystone is available. They are also a viable alternative to monolithic structures where the foundation material
lacks the strength necessary to support a monolithic-type
structure. Rubble-mound breakwaters are used extensively
in harbor construction because their porosity minimizes
disturbances caused by wave reflection inside the harbor
(Sharp and Khader 1984). Rubble-mound structures are
widely used throughout the world, so naturally, stability
tests of rubble-mound structures are the most frequently
conducted coastal structure model (Oumeraci 1984).