United States Patent
`Hayes et al.
`
`3,670,504
`15)
`(45) June 20, 1972
`
`54 FABRIC CONTAINMENT
`CONSTRUCTIONS
`72 Inventors: John T. Hayes, Durham; Robert G. Curri-
`er, Roxboro, both of N.C.
`N
`ti
`r
`Aik
`C
`73) Assignee s:
`d
`man Uorporation, New
`
`3,224,466 12/1965 Grover............................ 139/20
`3,299,640 l/1967 Neilsen........................................ 6/3
`3,396,545 8/1968
`Lamberton.
`...6/47
`3,425,228 2/969 Lamberton....
`...61/38
`
`Primary Examiner-Peter M. Caun
`Attorney-Paul & Paul
`
`56)
`
`Feb. 5, 1968
`Filed:
`(22
`(21) Appl. No.: 702,925
`
`ABSTRACT
`57
`A dual-wall fabric is provided, with integrally woven drop
`stitches connecting opposite walls thereof, the fabric being
`adapted to receive a filler material between walls thereof, the
`E.O.E. filler material being preferably cast therein, such as concrete,
`issi Field of search. 77.38, and the fabric walls being of desired materials and weaves to
`61f47; 139/20, 410; 52/2; 66/18 E
`yield desired porosities. One or both of the walls may be con
`a Ws
`structed of a material having a specific gravity less than water,
`o
`to facilitate floating of the same in water. Prior to filling the
`dual-wall fabric with concrete or the like, reinforcing rods
`References Cited
`UNITED STATES PATENTS
`may be interspersed between the connecting drop stitches.
`The dual-wall fabric, or a single-wall fabric may be anchored
`2,209,874 7/1940 Dempsey............................... 139/410
`along beaches, canals and the like, into canopy-like configura
`2,632,480 3/1953
`MacIntyre....
`tions or structures, which structures may be filled with sand or
`as 139/410
`877,201
`111908
`Kellner........................................ 61/3
`other natural fill, the mound or sand bar thus formed being
`1,815,196 71931 French et al....................... 160/17E
`then covered by a concrete-like material. In the case of a dual
`2,185,458
`1/1940
`Giliasso.......................................6115
`wall fabric construction, concrete may be pumped between
`2,657,716 1 1/1953
`Ford.............
`-1399 the fabric walls, to provide a concrete-like outer encasement
`2,939,467 6/1960 Meyer et al.................................. 5212
`for the sandbar or the like thus formed.
`3,008,213 1 1/1961
`Foster et al......
`.139,410 X
`3,188,813 6/1965
`Foster et al.................................. 6115
`4 Claims, 11 Drawing Figures
`
`
`
`
`
`
`
`
`
`
`
`NY/XX
`OS
`X {& KS3
`SNY).
`
`Metromont Ex-1015, p.1
`
`

`

`PATENTED JUN2O 1972
`
`3, S7 O,504
`
`SHEET 1 OF 3
`
`
`
`INVENTORS.
`JOHN T. HAYES
`ROBERT G. CURRER
`
`BY
`
`ATTORNEYS.
`
`Metromont Ex-1015, p.2
`
`

`

`PATENTED JUN2O 1972
`
`3, 670,504
`
`SHEET 2 OF 3
`
`
`
`A/g 7
`
`BY
`
`INVENTORS.
`JOHN HAYES
`ROBERT G. CURRER
`
`(2-6-6-6
`
`ATTORNEYS.
`
`Metromont Ex-1015, p.3
`
`

`

`PATENTED JUN20 1972
`
`3, S7O,504
`
`SHEET 3 OF 3
`
`
`
`BY
`
`INVENTORS.
`JOHN T. HAYES
`ROBERT G. CURRER
`
`(2-6-6-6
`
`ATTORNEYS.
`
`Metromont Ex-1015, p.4
`
`

`

`1.
`FABRC CONTAINMENT CONSTRUCTIONS
`
`3,670,504
`
`5
`
`15
`
`25
`
`35
`
`BACKGROUND OF THE INVENTION
`Dual-wall fabric constructions in themselves, are known in
`the prior art, even those having integrally woven connecting
`threads, such as are used for inflatable mattresses and the like.
`However, the prior art is devoid of any teaching of utilizing a
`dual-walled fabric construction having integral drop-stitch
`thread connections, and which is filled with a filler material,
`preferably of the structural type, such as cast concrete, grout,
`cement or the like, or even plastics or foams. Furthermore, the
`prior art is devoid of any teaching of a dual-walled fabric hav
`ing integral connecting threads, wherein the fabric, in its
`finished form is porous, to permit the passage therethrough of
`moisture from a castable, filler material, such as concrete or
`the like. Still further, the utilization of such dual-walled or
`even single-walled fabrics having specific gravity less than
`water to utilize the effect of the buoyancy of such fabrics in
`water in order to maintain a canopy-like shape of a fabric
`sheet during the filling of the same with a natural fill, such as
`sand, for purposes of constructing sand bars, sea walls, groins,
`coffer dams and the like, is nowhere taught in the prior art.
`With particular regard to the construction of sand bars and
`the like, in many costal areas and the like, soil erosion and
`beach conservation are continuing problems, with sea cur
`rents, tides, etc., continuously sweeping off the natural fill
`from the beach surfaces. In many instances such erosion is
`prevented by sinking pilings and the like, or by dropping
`pilings or tetrapeds into the beach area. However, heretofore,
`sand mounds formed by prior art techniques have not success
`fully built up sand mounds such that the sloping mound sur
`faces have a greater than 25° angle with the seafloor.
`Other beach conservation processes have been proposed,
`but none have been adapted toward quick installation result
`ing from the use of prefabrication techniques, resulting in
`economically installed sand bars and the like of a permanent
`nature.
`
`SUMMARY OF THE INVENTON
`The present invention seeks to obviate and overcome the
`above and other deficiencies in prior art dual-wall fabric con
`structions for structural purposes and erosion control
`techniques, in providing a dual-wall fabric having connecting
`threads integrally woven therewith, which is adapted to
`receive a concrete or similar fill material therein, and which
`permits water drainage therethrough of the concrete during
`setting, with various types of drop-stitch weave constructions
`for desirably balancing stresses, and with reinforcing rods
`being optionally provided.
`The fabric may be constructed to have one or more walls of
`a material, such as polypropylene, which has a specific gravity
`less than that of water, such that the buoyant effect of water
`would normally tend to float the fabric in water. Accordingly,
`by desirably anchoring such a fabric, either of single or of
`dual-wall construction, such that it is sufficiently loose to tend
`to "float', and assume an arcuate shape or configuration, the
`fabric may then be filled either by pumping the fabric with
`sand or other natural fill, or by utilizing a fabric mesh of suffi
`ciently loose construction to permit the passage of sand
`therethrough, whereby the fabric "dome' or the like may be
`filled by the natural motion of sand or other natural fill along
`the sea floor. The anchoring means can comprise concrete
`65
`filled fabric tubes which are connected longitudinally to the
`dome shaped fabric construction, along edges thereof ad
`jacent the sea floor. If the fabric surface is of double-walled
`construction, the same may be pumped full of concrete or the
`like, after the dome shaped construction is filled with sand,
`and after hardening of the concrete, the structure is substan
`tially permanent. If the fabric material of the dome construc
`tion is of single-wall thickness, a concrete or the like over
`covering may be provided for the dome or sand bar thus
`formed.
`
`70
`
`75
`
`2
`These same principles, such as that of utilizing materials
`which have a specific gravity less than water to substantially
`float the same in water, for the purpose of sea-wall construc
`tion, are also within the scope of this invention, whereby a ver
`tical wall may be formed by a sheet of loosely woven mesh,
`which is anchored at one end against the sea floor, whereby
`Sand can gradually accumulate against sides of the sea wall, to
`form a sand bar or the like, the bar being adapted to be then
`made permanent by receiving an over-covering of concrete or
`10
`the like, if desired,
`Accordingly, it is a primary object of this invention to pro
`vide a novel dual-wall fabric having a pair of opposed woven
`fabric layers interconnected by integrally woven dropstitches,
`the dual-walled fabric being adapted to receive concrete or
`the like materials therein, for facilitating the provision of
`desirable structures.
`It is another object of this invention to accomplish the
`above object, wherein the drop stitches are disposed at a
`desirable angular relation with respect to the opposed fabric
`layers, for distributing stresses and pressures in a desirable
`fashion, such stresses and pressures resulting from the filling
`of the dual-wall fabric by a desired filler material.
`It is a further object of this invention to accomplish each of
`the above objects, wherein the fabric layers are of selected
`porosities and specific gravities, for the respective purposes of
`facilitating "breathing" of a cast filler material through the
`fabric walls, and for facilitating a buoyancy of the fabric when
`immersed in a liquid, such as water.
`It is another object of this invention to provide a structural
`member of dual-walled fabric construction having integrally
`woven connecting stitches at desirable angular relationships
`with respect to the opposite walls, wherein reinforcing rods
`are provided interspersed throughout a filler material disposed
`between the fabric walls.
`It is a further object of this invention to provided beach ero
`sion and control structures which may be substantially
`prefabricated and which are relatively easy to install un
`derwater, and which utilize, to a substantial degree, the natu
`40
`ral fill of the seafloor in their construction, but which when in
`stalled, may be readily made permanent.
`It is a further object of this invention to provide substan
`tially permanent beach conservation structures and the like,
`which utilize floatable fabric materials weighted along op
`45
`posite sides to form a dome construction which, when filled
`with sand, may be either covered or ; have an outer surface
`portion thereof pumped full of concrete or the like, to provide
`an artificial sandbar construction.
`It is yet another object of this invention to provide a sea-wall
`50
`construction for collecting natural fill thereabout, which may,
`then be covered with a concrete or cement layer, if desired,
`but which utilizes a buoyancy effect on the material of con
`struction of an anchored sea wall, to maintain the same in a
`vertical plane underwater, during collection of the natural fill
`thereabout.
`It is a further object of this invention to provide a novel
`method for the formation of beach erosion-control structures,
`utilizing constructions which may be substantially
`60
`prefabricated and readily installed and completed in situ.
`Other objects and advantages of the present invention will
`become readily apparent to one skilled in the art upon a
`detailed study of the following brief figure descriptions, the
`detailed descriptions of the preferred embodiment, and the
`drawings and appended claims.
`BRIEF DESCRIPTION OF THE FIGURES
`FIG. 1 is a fragmentary top perspective view of a dual
`walled fabric of this invention, wherein integral connecting
`drop-stitch strands are illustrated disposed at acute angles to
`the opposed fabric walls.
`FIG. 2 is an enlarged fragmentary schematic view of the
`dual-walled fabric of FIG. 1, as it would appear in view taken
`along the line II - II of FIG. 1, looking transverse of the
`
`55
`
`Metromont Ex-1015, p.5
`
`

`

`5
`
`15
`
`3,670,504
`
`3
`4.
`machine direction of weave, with the connecting strands being
`A plurality of connecting strands 18 comprise stitches of the
`of repetitive generally X-shaped configuration, with a portion
`drop-stitch type, the strands 18 being integrally woven into the
`of the view being generally indicative of the appearance of the
`dual-wall fabric 15, and comprising the same material as that
`dual-walled fabric construction when the same is filled with
`of the upper wall or layer 16. Thus, if the material comprising
`concrete or the like.
`the strands which form the upper layer 16 is of polypropylene,
`FIG. 3 is a schematic end view of the dual-walled fabric of
`the connecting strands 18 are also of polypropylene. It will be
`FIG. 1, taken generally in the machine direction along the line
`noted that there is a high density of connecting strands 18
`III - III of FIG. 1, wherein the vertical disposition of the angu
`between the walls or layers 16 and 17, for purposes of dis
`larly disposed connecting strands, as viewed endwise, is
`tributing tensions and pressures, in a manner to be described
`clearly illustrated.
`O
`below.
`FIG. 4 is a view similar to that of FIG. 3, but of a dual-walled
`With particular reference to FIG. 2, it is seen that the
`fabric construction, wherein a plurality of connecting strands
`strands 18, formed by the drop-stitch method, are disposed at
`are aligned, transversely of the machine in side-by-side rela
`acute angles of substantially 45 between the upper and lower
`tion, to yield a tape-like connecting stitch or web construc
`layers 16 and 17, respectively. With reference to FIG.3 also,
`tion.
`it is seen that the strands 18 lie substantially in common
`FIG. S is a view similar to that of FIG. 2, of a drop-stitch
`planes, spaced transversely of the machine, or transversely of
`construction having connecting strands angularly disposed in
`the direction of fabric travel during manufacture. Thus, each
`repetitive X-shaped configuration, to provide connecting
`strand comprises a dropped warp strand, and is connected to
`stitches, of web form, sufficient for withstanding to a large
`or woven around transverse strands in each of the upper and
`20
`degree, pressures which would tend to separate opposed
`lower layers 16 and 17, respectively. With continued
`fabric layers resulting from applying a fill between the op
`reference to FIG. 3, it is seen that the transverse spacing of the
`posed fabric layers, but wherein there are illustrated reinforc
`drop strands 18, 18, 18', etc. across the machine, during for
`ing rods, disposed throughout the connecting strands, between
`mation of the dual-wall fabric 15 may be altered, as desired, to
`the fabric walls.
`increase the transverse density of the drop strands, as desired.
`25
`In FIG. 6 there is illustrated a side view of a dual-walled
`As illustrated at the right side of FIG. 2, the dual-wall fabric
`fabric construction in schematic form, generally similar to that
`15 is filled with concrete 21. It is to be understood that the
`of FIG. 2, but wherein the individual connecting strands are
`term "concrete' is to be construed as being sufficiently broad
`disposed at right angles to each of the opposed fabric walls.
`to encompass cement, grout, mortar, and other similar materi
`In FIG. 7 there is illustrated in side view a preliminary stage
`als. The concrete 21 may be pumped or otherwise placed
`30
`of formation of the fabric constructions of FIGS. 2 and 5, prior
`between the layers 16 and 17 of the dual-walled fabric 15, in
`to separation of the opposed fabric layers.
`wet form, and allowed to set or become "cast' therebetween,
`FIG. 8 is a fragmentary top perspective view of an artifi
`such pumping possibly exerting high pressures tending to
`cially formed sand bar formed of a dual-walled fabric of this
`separate or more greatly space the upper and lower walls or
`invention which is provided with concrete-filled fabric tubes
`layers 16 and 17, respectively. The greater such pressure from
`35
`as anchoring means for the fabric during filling of the space
`pumping concrete 21 into the fabric 15, the more dense
`between the fabric and ocean floor with sand or the like, the
`should be the placement of connecting strands 18. As has
`dual-walled fabric being later filled with concrete or the like,
`been set forth above, it may be desirable to have the upper
`between its opposed walls to result in a permanent structure,
`layer 16 to be less dense than a lower layer 17, with respect to
`with an end portion of similar construction also being illus
`the weave construction, in order that the upper layer 16 may
`40
`trated.
`be more porous, to permit the passage of moisture or water
`FIG. 9 is an enlarged fragmentary sectional view taken
`therethrough as the concrete 21 becomes set or cast. In some
`generally along the line IX - IX of FIG. 8, wherein the dual
`applications, it may be desirable to have both upper and lower
`walled fabric of construction of the bar of FIG. 8 is more
`layers 16 and 17 to be sufficiently porous for this purpose, but
`clearly illustrated.
`in some instances, if the fabric 15 is to be used as an upper
`FIG. 10 is a cross-sectional view, in schematic form, of an
`most covering for an artificial sand bar, such as that of the
`underwater artificial sand bar formation, utilizing a floatable
`type illustrated in. FIG. 8, it is most desirable to have a lower
`fabric of single-walled construction, the bar structure being
`fabric surface 17 of tight weave construction, to retain sand
`otherwise similar to that of FIG. 8.
`particles therein, but to have an upper fabric layer 16 of loose
`FIG 11 is a cross-sectional view of an underwater sea-wall
`weave construction, to contain the concrete therein, but to
`SO
`construction, in schematic form, wherein the sea-wall is main
`permit the passage of excess water therethrough.
`tained in vertical position due to the buoyant effect of the
`It is to be noted that the fill need not be concrete 21, but in
`water thereon, while sand accumulates about the lower
`many instances and applications the filling material may
`anchored end of the sea wall.
`desirably be a suitable hardenable plastic, or foam, such as
`Referring now to the drawings in detail, reference is first
`polyurethane foam. However, regardless of the filling materi
`55
`made to FIG. 1, wherein there is illustrated a dual-wall fabric
`al, foam, plastic, concrete or the like, such will have sufficient
`construction, generally designated by the numeral 15, which
`qualities for immersion of the connecting strands 18 therein.
`comprises spaced upper and lower walls or layers 16 and 17,
`With particular reference to FIG. 4, it is to be noted that a
`respectively.
`plurality of strands 22, 23, 24, 25 and 26 may be aligned in
`The upper wall 16 of the construction 15, as illustrated is
`side-by-side relation, threaded into a repetitive X-shaped side
`60
`preferably of a loose weave construction the fibrous material
`view configuration as illustrated in FIG. 2, if desired, the end
`being of any suitable material, such as nylon, polyethylene, "-
`view configuration of FIG. 4 being particularly illustrative of
`foamed" polypropylene, or "foamed" nylon, but preferably of
`an embodiment whereby several connecting strands 22, 23,
`polypropylene fibers, particularly if the fabric 15 is to be used
`24, 25, 26 are operative, each similar to an individual connect
`underwater, in applications where it may be desirable to verti
`ing strand 18, but wherein the several strands cooperate to
`65
`cally separate the upper layer 16 from the lower layer 17. In
`form a "tape-like' connecting stitch or web between spaced
`the latter instance, the water would have a buoyant effect on
`upper and lower fabric walls 27 and 28, respectively.
`the polypropylene layer 16, due to the specific gravity (0.9) of
`In FIG. 5, there is illustrated a dual-wall fabric, generally
`polypropylene, as compared to that of water (1.0).
`designated by the numeral 30, similar to that 15 of FIG. 2, and
`The lower wall or layer 17 may be of a more tightly woven
`having spaced upper and lower walls or layers 31 and 32,
`70
`fibrous construction, as illustrated, if porosity of this lower
`respectively, interconnected by drop threads or strands 33,
`layer is not desirable, as for example, if the lower layer is to be
`also disposed at acute angles with respect to the upper and
`used for sand containment, as illustrated in FIGS. 8 and 9. The
`lower walls 31 and 32. In the embodiment of FIG. 5, a plurali
`fibrous materials from which the lower layer 17 is constructed
`ty of reinforcing rods 34, 35, 36 and 37, are illustrated
`may be nylon, or similar materials if desired.
`75
`disposed in spaced relation to each of the walls 31 and 32, and
`
`45
`
`Metromont Ex-1015, p.6
`
`

`

`15
`
`35
`
`3,670,504
`S
`6
`retained in such positions by the crossing connecting strands
`fabric fills with concrete 21. Upon setting of the concrete 21,
`33. Thus, a structure such as that 30, may be used for other
`and setting of the concrete which fills the tubular fabric por
`construction purposes, being reinforced with steel or iron
`tions 70, 71 and 76, the sand bar 60 becomes a substantially
`rods, cables or the like, if desired, prior to filling the fabric 30
`permanent construction. It will be apparent, that the length of
`with concrete (not shown) or other filler material. Such rods
`the sand bar 60 may be set as desired, the individual fabric
`may be hollow for carrying power and communciation wires
`strips 65 being capable of manufacture to the desired length of
`and cables, water pipes, steam lines, etc.
`a particular sandbar 60 to be constructed.
`In FIG. 6 there is illustrated another alternative embodi
`In FIG. 10 there is illustrated a fabric construction 80,
`ment of a dual-wall fabric 40 comprising upper and lower
`generally similar to the canopy 64 of FIG. 8, having tubular
`O
`layers 41 and 42, connected by individual or plural strands 43,
`portions 82 and 83 stitched or otherwise secured to opposite
`disposed between the layers 41 and 42, at substantially right
`longitudinal edges thereof, but wherein the fabric material
`angles to the plane of each of the layers 41 and 42, such
`between the tubular portions 82 and 83 comprises a single
`strands 43 being formed by a straight through drop stitch
`thickness sheet of polypropylene or other lighter-than-water
`method, should the same be desirable. The dual-wall fabric 40
`materials, or even a dual-wall fabric if the same is desired. In
`may also be filled with concrete or the like, as desired.
`the embodiment of FIG. 10, the fabric construction 80 if
`In FIG. 7 there is illustrated a basic weave formation 50
`placed into the water 84, with the tubular portions 82 and 83
`used to attain the dual wall fabrics 15 or 30 of FIGS. 2 or 5,
`on the bottom surface or beach floor 85 thereof, and the tubu
`respectively, having opposed layers 51 and 52 connected by
`lar portions 82and83 are again weighted, as by pumping them
`drop strands 53, illustrated at small acute angles with respect
`full of concrete or like filler. The buoyant effect of the water
`20
`to the layers 51 and 52, prior to separation of the layers 51 and
`84 on the polypropylene or other light sheet 81 then permits
`52 an amount such as those layers 31 and 32 of FIG. 5, for ex
`the sheet 81 to take on the form illustrated in FIG. 10, to be of
`ample, and thus prior to the strands 53 taking on the X-shaped
`arcuate construction. The particular weave of the sheet 81
`configuration of the strands 33 of FIG. 5. The strands 53 may
`permits water currents, tidal waters, or the like to carry sand
`be woven with various heights of gage wires 54, depending
`or other natural bottom fill 86 through the loose weave of the
`25
`upon the number of crossings of the gage wires 54 and the
`sheet 81, such that it will gradually fill the void 87 beneath the
`height of the gage. The distance between the fabric layers 50
`arcuate sheet or canopy 81 until the sand takes on an inverted
`and 51 can be any desired height, to attain the desired layer
`U-shaped configuration. If a temporary bar is desired, the
`spacing of FIG. 5, for example. A normal distance between the
`structure may remain as illustrated in FIG. 10, or in the event
`layers 31 and 32 would be within the range 0.5 to 24 inches.
`that a permanent sand bar is desired, the surface 81 may be
`30
`With particular reference to FIG. 8, there is illustrated, in
`then covered with concrete-filled dual-wall fabrics such as the
`final formation, an artificially formed sand bar or the like,
`type illustrated in FIG.2.
`generally designated by the numeral 60, disposed substantially
`In FIG. 11 there is illustrated an alternative construction,
`entirely beneath the upper surface 61 of water 62, as on a
`for forming a sea-wall, wherein a sheet 90 of loosely woven
`beach or the like, having a floor or lower surface 63, of sand or
`polypropylene or other lighter-than-water material is pro
`like natural fill material.
`vided, having secured thereto at a lower end, a tubular fabric
`The bar 60 is adapted for channels, beaches, or the like, and
`construction 9, which when filled with concrete or other
`may have an uppermost portion protruding out of the water
`suitable material and placed on the beach floor 92, beneath
`62, above the surface 61 thereof, as illustrated, if desired. The
`the water 93, tends to anchor the sheet 90 in a vertical posi
`bar 60 is formed by a canopy 64 being provided, of a plurality
`40
`tion, the water having a buoyant effect on the material of con
`of longitudinal portions 65 of a dual-wall fabric 15, (as illus
`struction of the sheet 90. Additionally, another tubular fabric
`trated in FIG. 1) stitched together along seams 66, and along
`member 94 may be provided, secured to the uppermost end of
`opposite longitudinal edges 67 and 68 thereof having tubular
`the sheet 90, which may be filled with polystyrene or other
`fabric portions connected thereto as by stitching, or the like.
`buoyant pellets 95, or the like, to also facilitate maintaining
`Such tubular fabric portions are designated by the numerals
`45
`the sheet 90 in vertical disposition, again utilizing the buoyant
`70 and 71, respectively. At the end of the canopy 64 formed
`effect of the water on the pellets 95 to retain the tubular
`by the plurality of fabrics or sheets 15, is an end cover 72,
`member 94 directed toward the upper surface 96 of the water.
`which also comprises a plurality of fabric portions 73, stitched
`The structure illustrated in FIG. 11 is also operative during
`together along seams 74 and along the arcuate edge 75 at the
`natural currents, tides, and the like, whereby sand or other
`50
`ends of each of the portions 65, to close the end thereof. At
`natural fill 97 is conveyed along the beach surface 92, to accu
`the lowermost end of the end-wall fabric 72, there is provided
`mulate the same on opposite sides of the surface 90, around
`a tubular fabric construction 76, stitched thereto along a edge
`the weighted portion 91, such sand 97 gradually accumulating
`77 thereof, similar to those tubular members 70 and 71
`upwardly, as illustrated, to form a sea wall, which may then be
`stitched along the sides of the canopy 64. Thus, the entire
`made permanent, as by covering the same with concrete-filled
`fabric construction illustrated may be prefabricated, and car
`dual-wall fabric constructions, such as the type illustrated in
`ried to the area of installation, as on a boat or the like, from
`FIG. 2, if desired.
`which is may be dropped into the water 62, onto the sand Sur
`It is to be noted that the various tubular fabric portions 70,
`face 63, the tubular portions 70, 71 and 76, being pumped full
`71, 76, 82, 83, and 91 may be of nylon construction or the
`of concrete or the like, to provide weighted portions, for
`like, where the specific gravity of the same is not critical.
`60
`retaining the canopy 64 in position. Due to the lighter-than
`Also, should it be desired to have vent points in a dual-wall
`water material of construction of the canopy 65, or at least of
`fabric construction, such may be made by inserting a hollow
`the upper surface 16 thereof, the buoyant effect of water
`rubber, or polystyrene, or like ball, between the walls of a
`thereon will tend to fill out the shape of the canopy 64 into a
`fabric, such that, after the dual-wall fabric is grouted, or other
`generally arcuate configuration, as illustrated in FIG. 8, up to
`wise filled with concrete, the ball may be punctured, thereby .
`65
`the height of the water surface 61, at which level the canopy
`providing a hole for securing any desired attachment devices
`fabric would remain until the interior of the canopy 64 is
`to the concrete, such method of making vent points being sub
`stantially less expensive than drilling through concrete.
`pumped full of sand, or is otherwise filled with sand or other
`It is to be particularly pointed out that an advantageous fea
`similar natural fill material 78. After the fill material 78
`“rounds out' the canopy 64, the dual-wall fabric 15, as illus
`ture of this invention resides in the fact that the restrictive
`70
`trated in FIG. 9, may then be pumped full of concrete or the
`length of the drop threads or connecting strands prevents bal
`like, between the two layers 16 and 17, whereby the connect
`looning of the opposite fabric walls during the filling of the
`ing strands 18 will be immersed therein, the water 61 which is
`same with concrete, any of the styrenes, foamable materials
`present between the layers 16 and 17 being forced outwardly
`such as polyurethane, or the like, the strands also being opera
`through the loosely woven or porous layer 16, as the dual-wall
`tive for purposes of balancing the stresses which would tend
`
`55
`
`75
`
`Metromont Ex-1015, p.7
`
`

`

`3,670,504
`7
`toward expansion of the distance between the opposite fabric
`layers. Thus, the more dense the drop threads are, the greater
`will be the ability of the dual-wall fabric to balance stresses
`during filling thereof.
`In those instances where the alkaline content of the
`concrete, grout, etc. is sufficiently high to have a tendency to
`react with polypropylene or the like, thus causing a degrada
`tion of the layer fibers, and particularly of the connecting
`strands, those strands or layer fibers or both may be nylon, to
`eliminate any attendent degradation problem.
`It will be apparent to those skilled in the art that various
`modifications may be made on the various fabric containment
`constructions, and in the several specific applications of the
`same which are illustrated, along with changes in their as
`sembly and environmental applications, all within the spirit
`and scope as defined in the appended claims.
`What is claimed is:
`1. A dual-wall fabric for use in combatting soil erosion, such
`as in the construction of underwater dams, comprising a pair
`of opposed woven fabric layers having drop stitches woven in
`tegrally with and connecting said layers, said opposed layers
`being constructed of materials which have dissimilar specific
`gravity characteristics which are respectively greater and less
`than that of the water with which the fabric is to be used, such
`
`5
`
`8
`that the fabric, when immersed in water and expanded
`between the layers, one said layer is disposed buoyantly up
`permost in the water and the other said layer is spaced by
`gravity from the one said layer.
`2. The dual-wall fabric of claim 1 wherein the first said
`fabric layer is constructed of polypropylene material.
`3. The dual-wall fabric of claim 1 wherein the other said
`fabric layer is of nylon construction.
`4. A method of making an artificial waterbreak for beach
`O
`conservation and the like, comprising the steps of
`1. providing a dual-wall fabric sheet material having con
`necting strands and weighted longitudinal edges in in
`mersed relation, with the weighted edges spaced from one
`another on a below-water surface, a distance less than the
`width of the sheet material,
`2. providing natural fill in the space between the below
`water surface and the sheet material to force water from
`beneath the sheet material and to fully fill the space
`beneath the sheet material,
`and 3. filling the space between the opposite walls of the
`fabric sheet material with a hardenable concrete-like
`material.
`
`15
`
`ck
`
`xk
`
`sk
`
`2k
`
`xk
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`70
`
`75
`
`Metromont Ex-1015, p.8
`
`