Various breakwaters or harbor shelters have been known and used. The oldest variations in this art have been rubble mounds spilled to form shoals or causeways at the seaward boundaries of harbors. Such rubble mound breakwaters are laborious and therefore expensive to install, may be prone to erosion, and often induce silting of the sheltered harbor. Additionally, rubble mounds remain stable only while the side slopes are shallower than an angle determined both by the constituent rubble and by tidal flows. Accordingly, the volume of stone required for building a rubble mound increases roughly as the square of the bottom depth at the active boundary of a harbor to be sheltered. Nonetheless, shallow breakwaters continue to be constructed in this simple manner.
Where water depth or other factors may deprecate rubble mound breakwaters, caisson constructions have been used. Caisson breakwaters are understood to make use of generally vertical or sloping plates stacked and fastened together, from the bed upward, on at least the seaward face of a rubble fill. Thus, caissons generally can reduce the material requirements for building a breakwater. Placement and attachment of the caisson plates may, however, require significant skilled labor and equipment. Additionally, caisson construction tends to aggravate the silting problem well known from the overall more permeable rubble mounds.
With the forgoing problems and concerns in mind, it is the general object of the present invention to provide a protective maritime assembly and method which overcomes the above-described drawbacks.