CA1257975A - Floating breakwater - Google Patents

Floating breakwater

Info

Publication number
CA1257975A
CA1257975A CA000517418A CA517418A CA1257975A CA 1257975 A CA1257975 A CA 1257975A CA 000517418 A CA000517418 A CA 000517418A CA 517418 A CA517418 A CA 517418A CA 1257975 A CA1257975 A CA 1257975A
Authority
CA
Canada
Prior art keywords
modules
block
fingers
continuous
continuous block
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA000517418A
Other languages
French (fr)
Inventor
Robert J. Mckay
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Pacific Marina Developments Pty Ltd
Original Assignee
Pacific Marina Developments Pty Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Pacific Marina Developments Pty Ltd filed Critical Pacific Marina Developments Pty Ltd
Priority to CA000517418A priority Critical patent/CA1257975A/en
Application granted granted Critical
Publication of CA1257975A publication Critical patent/CA1257975A/en
Expired legal-status Critical Current

Links

Classifications

    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02ATECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A10/00TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE at coastal zones; at river basins
    • Y02A10/11Hard structures, e.g. dams, dykes or breakwaters

Landscapes

  • Revetment (AREA)

Abstract

ABSTRACT OF THE DISCLOSURE
A floating breakwater is constructed from a plurality of interconnected modules each having an internal core formed from floatable material and an external sheath formed from settable material. Each module is provided with a pair of oppositely extending flanges which abut the respective flanges of adjacent modules and all of the modules are secured together to define a continuous block by means of front and rear continuous strips which are secured to the modules by means of elongated fasteners. A plurality of finger modules extend outwardly from the continuous block in spaced relation and a continuous finger strip is secured to the outermost end portions of each of the fingers. A beam is secured between each pair of adjacent modules beneath the abutting flanges. Each beam extends out-wardly between the spaced apart fingers and is secured to each of the strips to strengthen the floating breakwater.

Description

~Z5'~9~5
2.

FLOATING BREAKWATER

This invention relates to a floating breakwater suitable for use in harbors for inhibiting wave action thereby providing a sheltered mooring location for boats and the like.
Floating breakwaters are mooring structures that float at or near the water surface and cause incident wave energy to be dissipated by reflectlon, turbulenae, drag, damping or other suitable means thereby causing wave heights to be reduced on the leeward slde.
Conventional floating breakwaters for the above mentioned purpose have included one type formed by a multiplicity of floating tires linked together by chain links, poles or rope and which are designed to cover a relatively large area. While such floating breakwaters have been found to be relatively inexpensive lt has also been found that they require a high degree of maintenance and are also particularly susceptible to storm damage.
Another type of floating breakwater includes the use o large rectangular or doughnut shaped concrete pontoons arranged in single rows or double parallel rows to present a ~o ~2S7~7~i fla-t or planar surface to wave action. rrhe pontoons were normally anchored with pil0s or moored to anchor blocks with chains or rope. However, it has been found if the wave heights exceeded three feet the use of concrete pontoons was disadvantageous because the articulated joints between the pontoons were highly stressed and often were broken. I'hus failure of the articulated joints was common.
In addition to the aforementioned disadvantages the conventional floating breakwaters as described above were su'bject to unsatisfactory performance in regard to insufficient attenuation of transmltted waves. Also structural failures and mooring failures were common.
It is the ob~ect of the invention to provide a floating breakwater which alleviates the problems of conven-tional floating breakwaters described above.
Briefly stated, the invention involves a breakwater comprising a continuous block formed by a plurality of modules, a rear block in-terconnection strip contacting each rear surface of the modules of said continous block and a fron-t block interconnection strip contacting each front surface of the modules of said continuous block, a plurality of spaced apart fingers disposed in engagement with said front block interconnection strip and e~tending outwardly away from said continous block, a continuous finger interconnection strip contacting the front surface of each of said fingers and an elongate beam secured between each pair of adjacent modules and extending outwardly from said continous block in spaced parallel relation to said fingers and means securing the beam to said continuous block to strengthen the breakwater.
In another aspect of the present invention there is provided a breakwater comprising a rear continuous block formed by a plurality of modules in abutting relation wherein each module has an internal sheath formed from floatable material and an external core formed from concrete, a rear block interconnection strip contacting each rear surface of said module of said continuous block and a front block interconnection strip contacting each front surface of said modules of said continuous block, a first ~S~

plurality of elonga-ted fasteners extending through and interconnecting said modules and said front and rear block interconnection strips, a plurality of spaced apart fingers each having a construction similar to the construction of each module disposed in engagement with said front block interconnection strip and extending outwardly away from said rear continuous block, a continuous finger interconnection strip contacting the front surface of each of said fingers and a second plurality of elongated fasteners extending through and interconneoting said strips, said fingers, and said rear continuous bloc~.
Preferably each module may be formed in a mold which initially supports the internal ~ore by wedges or the like so that the core is spaced from the inner surface of the mold.
Thereafter a metal (usually steel or iron) reinforcing mesh may be located on top of the internal core and a plurallty of -tubes formed suitably from plasticæ material interposad between the internal core and the reinforcing mesh. Thereafter concrete may be poured into the mold so as to fill up the space between the internal core and the inner surface thereof. Thereafter concrete may be poured onto the top surface of the internal core so as to form a top wall of the module enclosing the reinforcing mesh and a plurality of tubes formed from plastics material.
The breakwater may also include a plurality of outwardly extanding fingers or projections which preferably are equally spaced along the length of the continuous block. The fingers may be attached to the continuous block in any suitable manner such as by elonga-te fasteners such as through bolts extending through the rear continuous block and the length of each finger. It is also preferred that the spaces between adjacent fingers are approximately equal to the width of the fingers.
The fingers again may be formed in modules or standard shapes or lengths and if desired may comprise a similar shape to the modules comprising the continuous block. Preferably the con-tinuous block is rectangular but this is not essen-tial.
There also may be provided a front interconnection strip or beam which is orien-ted substantially parallel to the -æ;

SL~57~7~;;

interconnection strips described above in regard to the rear continuous block.
It is also desirable that there be provided a plurality of transverse beams which interconnect the front interconnection strip and which may extend rearwardly of the rear continuous block and which may also be suitably attached to both of the interconnection strips associated wit~h the rear continuous block.
In this embodiment each transverse beam may extend from the front interconnection strip and be interposed between adjacent fingers so that the transverse beam may also extend between adjacent modules of the rear continuous block.
The provision of the aforementioned transverse beams is advantageous in that they enable the ~loating breakwater to have a stiffening function and thus inhibit movement of the fingers relative to the rear continuous block. Without the transverse beams it is possible for the fingers to move up and down or undergo vertical oscillations relative to -the rear continuous block under wave action.
The foregoing and other objects, features and adva~tages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention given by way of example only as illustrated in the accompanying drawings.

~r~.
~s ~2~q~7~
6.

Figure 1 is a perspective view of a floating break~ater constructed in accordance with the present invention.

Figure 2 is a front view of the breakwater shown in Figure 1.

Figure 3 is a plan view of the breakwater shown in Figure 1.

Figure 4 is a front perspective view of a modified float~
ing breakwater constructed in accordance with the invention.

Figure 5 is a rear perspective.vie of the floating break-water shown in Figure 4.

Figure 6 is a plan view of the floating breakwater shown in Figure 4.

Figure 7 is a front view of the floating breakwater shown in Figure 4.

~æ~
7.
The breakwater 10 in the drawings includes a rear continuous block 11 formed by a plurality of ad~acent modules 12 which may be formed as described above and which are all manufactured in standard lengths. There is also shown opposed timber interconnectlon strips or whalers 13 which are located on the front and rear slde of block 11 and which are attached thereto by bolts 14.
Also shown are outwardly e~tending fingers or proJections 15 which may be formed in standard lengths simllar or di~ferent to modules 12. Also shown ls a front lnterconnection strlp or whaler 16 attached to ~ingers 15 by bolts 14. The fingers 15 may also be formed with plastics internal tubes 16A as is the case with modules 12 in the manner described above which may be aligned or oriented wlth each other so as to facilitate the insertion of connection bolts 14 to attach the fingers 15 to block 11. Each module 12 may have an internal core of foam material 17 and an outer shsath of concrete 18. Included in a top wall or layer 23 of sheath 18 are the plastios tubes 16A and reinforcing mesh 22. Located between each finger are recesses 19 .
It will be appreciated that the fingers 15 may be oriented to the longitudinal axis of block 11 at any appropriate angle suitably between five degrees and fifteen degrees for exampleO
However it is preferred that fingers 15 extend at right angles to the longitudinal axis of block 11.
The floating breakwater of the invention may be anchored by any suitable means such as by a rope (preferably formed from ~L2S79~5 8.
nylon) or chain to a stub pile driving into the ground or a heavy waight. Alternatively for more shallow water the breakwater may have attached thereto appropriate support brackets which have rollers angageable in appropriata tracks in anchor piles driven into the ground.
The essence of the invention .is based upon the discovery that by the establishment of a rear continuous block and frontwardly extending fin~ers that the impact of the waves will be broken upon impingement upon the fron-t surfaces 20 of fingers 15 and that when the waves extend into the recesses 19 that they will also implnge upon the opposed side surfaces 21 of recesses 19 so as to form an interference pattern which will result in at least partial cancellati.on o~ the wave trains created. This provides a simple and very effective breakwater system.
It will also be appreciated that the fingers 15 instead of being rectangular as illustrated may adopt any other convenient shape such as trapezoidal, triangular or polygonal. However the rectangular shape is preferred for ease of manufacture. Also the fingers 15 do not have to have the same length as illustrated but may have different lengths if re~uired.
Also in variation of the above, the through bolts may extend longitudinally of the block 11 instead of transversely as shown and the fingers 15 may be attached to the block 11 in any other suitable manner such as by welding of adjacent metal plates or by bolting together ad~acent attachment brackets.
In the modified arrangement as shown in Figures 4-7 there is shown a rear continuous block formed by modules 12A which 9.
are each separa-ted by transverse beams 24, which are attached to front strip 1.6 at 25, -to a pair of intermedlate strips 13A at 26 and to a rear strip 13A at 27.
As best shown in Figure 5 each transverse beam 24 extends in recesses 29 which are ~ormed between abutting modules 12A as shown. In this arrangement each module 12A is provided with a pair of side flanges 28 which abut as shown above an adJacent recess 29.
In Figure 6, instead of through bolts 14 each extending through adjacent modules 12 and 15 as shown in Figures 1-3, it is also appropriate in some cases to use separate through bolts wherein through bolts 14A may be used to interconnect rear strip 13A and intermediate strip 13A through modules 12A and through bolts 14B may be used to interaonnect ront strip 16 and one of the intermediate strips 13A. Thus through bolts 14A and 14B do not connect with each other in the embodiment shown in Figure 6.
Also as best shown in figures 6-7, it is preferred that the width of fingers 15A are approximately e~ual to the spacing 19 between individual fingers 15A.
In the arrangement shown in Figures 4-7 the floatlng breakwater shown is a rigid structure and both the fingers 12A
and modules 15A are inhibited from relative movement especially by the incorporation of beams 24.
The provision of the front strip 16 is mainly responsible for causing wave turbulence and in tests carried out with a full scale prototype strip 16 caused approximately fifty percent of any wave front higher than 15 inches to break and spill over the strip 16 into spaces 19 thus causing a high degree of ~$5'7~'75 10 .
turbulence. Spaces lg also promote turbulence as also is the case with beams 24.
In regard -to reflection of waves in relation to waves incident on the floating breakwater at ninety degrees such waves were ~ound to be reflected by the outer fingers 15A, strip 16 and the rear continuous block ~ormed by modules 12A. In relation to wave incidence at angles other than ninety degrees re1ection of these waves occurred through the agency of end surfaces 20 of ~ingers 15A, side surfaces 30 of fingers 15A, beams 24 and the rear continuous block.
In regard to the relatively lars~e surface area exposed to the water by the present invention, especially in comparison with the a~orementioned conventional concrete pontoons it was noticed that a drag effect was obta~ned which was previously only obtainable with the aforementioned conventional breakwaters formad by a mul-tiplicity of floating tires.
A damping effect was also obtained which could be attributed to the mass of the total structure and in particular the rear continuous block.
Other advantages obtainabls by the floating breakwater o~
the invention are set out below.
Response: Because the buoyancy of the outward extended ~ingers is approximately fifty percent less than the rear continuous block the whole structure does not oscillate about its longitudinal axis as is common with other concrete pontoon floating breakwaters. ~n oscillation of this type tends to allow waves to pass through the breakwater.

~5'7g7~
11 .
Moorin~ Forces: The staggered profile presented to the lncoming waves reduces the forces on the moorings. If the outward extending fingers are so dimensioned to have a length equivalent to a half wave length the pressure forces are out of place by one hundred degrees.
Cost: As all components used for the present invention can be "off the shelf" items in normal use for the construction of regular floating marinas, the cost o~ this breakwater is minlmal.
Maintenance: The concrete encased pontoon type floating marinas have proven to reguire minimal maintenan~e and as the construction of the presant invention is similar the maintenance of this inventlon will also be minimal.
Damage: As there are no articulated ~oints and the whole structure has a controlled flexibility, the power to withstand storm damage of the present invention is better than other floating breakwaters in use.
Combination Floating Breakwater and Marina Berths: Because the structure of the present invention can be made from regular pontoons, the rear continuous block can have regular fingers attached on the leeward side to form marina berths. This further improves the performance of the structure as a wave attenuator and also reduces overall costs of marina berths. The seaward side of the ~loating brea~water can also be used for temporary mooring of boats during calm water periods.

s It will also be appreciated that a plurality of front strips 16 may be used instead of the single strip illustrated and the same applies for intermediate strips 13 or 13A and rear strips 13 or 13A. It also will be appreciated that a plurality of beams 24 may also be utilized which may extend through a respective spacing 19.
While the invention has been particularly shown and described with reference to preferred embodiments thereof it will be understood by those in the art that the foregoing and other changes in form and details may be made therein without departing from the spirit and scope of the invention.

Claims (4)

WE CLAIM:
1. A breakwater comprising a rear continuous block formed by a plurality of modules in abutting relation wherein each module has an internal sheath formed from floatable material and an external core formed from concrete, a rear block interconnection strip contacting each rear surface of said module of said continuous block and a front block interconnection strip contacting each front surface of said modules of said continuous block, a first plurality of elongated fasteners extending through and interconnecting said modules and said front and rear block interconnection strips, a plurality of spaced apart fingers each having a construction similar to the construction of each module disposed in engagement with said front block interconnection strip and extending outwardly away from said rear continuous block, a continuous finger interconnection strip contacting the front surface of each of said fingers and a second plurality of elongated fasteners extending through and interconnecting said strips, said fingers, and said rear continuous block.
2. A floating breakwater as set forth in Claim 1 wherein each of said modules is provided with a pair of oppositely extending side flanges adjacent the upper surface of each module and disposed in engagement with respective flanges of adjacent modules when said modules are disposed in abutting relationship to define said rear continuous block, an elongated beam secured between each pair of adjacent modules beneath said abutting flanges and extending outwardly from said rear continous block in spaced parallel relation to said fingers and means securing said beam to said modules and each of said strips to strengthen said floating breakwater.
3. A floating breakwater as set forth in Claim 2 wherein each of said fingers have an identical width approximately equal to the spacing between individual fingers.
4. A breakwater comprising a continuous block formed by a plurality of modules, a rear block interconnection strip contacting each rear surface of the modules of said continuous block and a front block interconnection strip contacting each front surface of the modules of said continuous block, a plurality of spaced apart fingers disposed in engagement with said front block interconnection strip and extending outwardly away from said continuous block, a continuous finger interconnection strip contacting the front surface of each of said fingers and an elongate beam secured between each pair of adjacent modules and extending outwardly from said continous block in spaced parallel relation to said fingers and means securing the beam to said continuous block to strengthen the breakwater.
CA000517418A 1986-09-03 1986-09-03 Floating breakwater Expired CA1257975A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CA000517418A CA1257975A (en) 1986-09-03 1986-09-03 Floating breakwater

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CA000517418A CA1257975A (en) 1986-09-03 1986-09-03 Floating breakwater

Publications (1)

Publication Number Publication Date
CA1257975A true CA1257975A (en) 1989-08-01

Family

ID=4133855

Family Applications (1)

Application Number Title Priority Date Filing Date
CA000517418A Expired CA1257975A (en) 1986-09-03 1986-09-03 Floating breakwater

Country Status (1)

Country Link
CA (1) CA1257975A (en)

Similar Documents

Publication Publication Date Title
US4979453A (en) Floating dock system
US3969901A (en) Floating breakwaters
US7390141B2 (en) Wave-attenuating system
US4693631A (en) Floating breakwater
US4479740A (en) Erosion control device and method of making and installing same
US5123780A (en) Precast permeable breakwater unit
US5707172A (en) Floating wave attenuators
US5107784A (en) Docking system for boats
US7575396B2 (en) Wave attenuation system
US5429452A (en) Floating break water structure
WO1997032086A1 (en) Sand dune and shore-line erosion prevention system
US4098086A (en) Breakwater
US4406564A (en) Breakwater
US5141359A (en) Zigzag breakwater
US6715958B2 (en) Floating wave attenuator
CN113737714B (en) Construction method of ecological floating breakwater
US5645371A (en) Bulkhead system
US4642000A (en) Anchoring system for concrete floating pier
US5062739A (en) Zigzag breakwater
CA1257975A (en) Floating breakwater
CN211312407U (en) Buoy type breakwater
JP3405605B2 (en) Sea area control method using submerged piles
JPH0415778Y2 (en)
JP3440854B2 (en) Reflected wave reduction structure with double-draft double curtain wall
GB2065569A (en) Floating breakwaters

Legal Events

Date Code Title Description
MKEX Expiry