Abstract: A prefabricated composite element for building, together with a plurality of similar elements, a breakwater sea wall comprising a pole having a poligonal cross section with a pointed tip, supporting a plurality of breakwater arms threaded in succession upon the pole in a progressively offset manner according to the edges of the pole.

Abstract: A concrete module for at least partial submergence in the surf to dissipate the energy of wave action and to promote the deposition of beach-restoring sand and pebbles comprises a series of passages which converge toward the shore-facing side of the module and terminate in an upwardly-directed opening which deflects the incoming water flow upward to further dissipate the wave energy and to create a reaction force on the module which tends to rotate or tilt it toward the shore. This tendency aids in neutralizing the natural tendency of barriers to rotate toward the sea as a result of sand being scoured out from beneath the seaward side of the barrier as a result of downwardly-deflected incoming wave energy.

Abstract: Each disc of a plurality of strings of concrete discs is pinned at opposite edges to a connecting link, a link between adjacent discs to form a chain. Alternate discs in the string lie substantially in the same plane, adjacent discs lying in intersecting planes. The discs stand on edge to prevent substantial erosion of soil from one side of the string to the other.

Abstract: Concrete structures consist of fabric containers which are filled with concrete through an opening in the top thereof while the top of the container is suspended from a portable support frame placed over the container. The support frame supports the container in an open and upward position with the bottom wall of the container resting on the ground while concrete is pumped or chuted into the container through the top opening.

Abstract: A concrete breakwater module for use with like modules positioned side-by-side in a line along or offshore from a beach or bluff for preventing erosion due to wave action and for reversing previous erosion. Each module has a single, large, upwardly concave, wave-energy-absorbing trough of partly cylindrical and partly flat-bottomed contour adjacent rear and front upright walls respectively located at opposite ends of a bottom, base wall. The front wall has a sloping front end surface directing incoming waves and spray over the trough. The rear wall is substantially higher than the front wall to intercept waves and spray and re-direct them downwardly along a cylindrical surface and forwardly in the trough providing a rolling and swirling action of water which erupts at the front wall in a countercurrent manner against waves and spray overtopping the front wall.

Abstract: An artificial seaweed, or "asymmetric seaweed", system for preventing shoreline erosion and/or causing sand accretion on beaches under wave action.

Abstract: A sealing system for an earthen container such as a pit, lagoon, land fill or the like for storing waste materials includes an outer seal layer formed by mixing a water expandable colloidal clay, such as bentonite with the soil of the pit. A middle or intermediate layer is defined by a layer of granular fill material placed on the first layer. An inner seal layer is formed by mixing water expandable colloidal clay, such as bentonite with the upper surface of the granular fill layer. A source of pressurized clean fluid is in communication with the granular fill layer to develop pressure therein and prevent leakage through the inner seal layer. Level sensing apparatus for sensing the level of waste and clean fluids may be included and apparatus for detecting leakage may also be included.

Abstract: An off-shore reef-like structure for preventing beach erosion. The structure comprises a string of prism-shaped modules placed in side-by-side relation in the surf area along a line defined by a sand bar, for example, where waves normally break. Each module has oppositely inclined front and rear walls adapted to face seaward and landward, respectively. At least one flow control passage extends through the module so as to converge from its front to rear wall openings. Incoming waves flow through the passage in a manner dissipating the wave energy while minimizing the wave impact forces tending to move the module. An opening is provided in the module bottom wall in communication with a through conduit enabling the module to fixedly seat or interlock itself in either sandy or coral-like shoreline areas. The module is uniquely designed to provide a minimal air lifting load for helicopter installation.

Abstract: An offshore reef assembly having rows of reef members of concrete or similar material with the configuration of each of the reef members providing inclined side faces arranged in grooves and ribs. The reef members may be formed by stacking blocks in the form of frustums of pyramids or cones. The interaction of the inclined side faces of the adjacent reef members with the vertically moving water caused by waves dissipates kinetic energy of the water and results in the deposition of sand and particulates on the bottom around the reef assembly.

Abstract: An arrangement for concentrating sea waves, includes a grid-like structure of stopping and/or delaying elements adapted to influence the amplitude and/or phase of the waves and located in such positions in the water that the elements in interaction with the incident sea waves form an interference pattern which gives a concentration of the wave energy in a limited area (concentration area). When the wave energy is to be utilized for power production, the grid-like element structure is designed to give a concentration of the wave energy in a concentration area located in the short-range field of the element structure. Preferably the elements in the structure are mainly situated in front of the concentration area with respect to the dominant wave incident directions. Moreover, the element structure may have an extension (aperture) which is substantially larger than the wave length of the dominant waves at the location.

Abstract: In a breakwater which comprises a back wall, and at least one front wall pierced with holes to break up the impact of an incident wave, the improvements are proposed of providing a sloping back wall; of providing convex-concave indentations on the back wall; and of providing partitions to divide up the space between the back wall and the front wall or walls. Various embodiments include an embodiment with two front walls in which the holes in the rearmost front wall are smaller than the holes in the foremost front wall.

Abstract: An arrangement for concentrating sea waves, includes a grid-like structure of stopping and/or delaying elements adapted to influence the amplitude and/or phase of the waves and located in such positions in the water that the elements in interaction with the incident sea waves form an interference pattern which gives a concentration of the wave energy in a limited area (concentration area). When the wave energy is to be utilized for power production, the grid-like element structure is designed to give a concentration of the wave energy in a concentration area located in the short-range field of the element structure. Preferably the elements in the structure are mainly situated in front of the concentration area with respect to the dominant wave incident directions. Moreover, the element structure may have an extension (aperture) which is substantially larger than the wave length of the dominant waves at the location.