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FIELD OF THE INVENTION  
         [0001]    This invention relates to vessels such as swimming pools and more particularly to support systems having buttresses for walls of above-ground swimming pools.  
         BACKGROUND OF THE INVENTION  
         [0002]    The popularity of swimming pools, particularly in residential areas, continues to increase. This increased popularity is based at least in part on the availability of aesthetically appealing above-ground pools, whose durability permits cost-effective purchasing by consumers. Above-ground pools additionally are particularly useful in areas where substantial excavation is either impermissible or undesirable. In densely-populated regions, for example, residential lawns may not be sufficiently large to accommodate the space required for in-ground pools. Moreover, in some cases they may be inadequate to accommodate the equipment necessary to excavate in-ground pools, even if space for such pools exists. Alternatively, above-ground pools may be preferable because of the decreased time typically needed for installation (and, if necessary, removal) or the lesser maintenance requirements and costs often associated with them.  
           [0003]    Many substantially-permanent above-ground pools are generally either circular or oval in shape, with each type comprising multiple vertical walls and a frame. Because of their strength, galvanized steel or other compositions are usually chosen as materials from which the walls are made. Nonetheless, water pressure present at and near the bottoms of filled pools often requires the walls of above-ground pools to be braced for reliable performance. This bracing requirement is particularly pertinent in connection with oval pools, whose elongated side walls are especially vulnerable to collapse from the outward pressure exerted by the water contained therein.  
           [0004]    As a consequence of this vulnerability, existing oval above-ground pools are constructed with braces supporting the lower sections of their side walls. Each brace includes three pieces, denominated an “upright” portion, an “angled” portion, and a “connecting” portion. FIG. 1 illustrates such braces  10  of above-ground pool  14 , whose generally oval shape requires use of multiple vertical side walls  18 . As shown in FIG. 1, upright portion  22  extends upward from bottom  26  of side wall  18 , with connecting portion  28  being either at ground level or buried underground. An end of each of upright portion  22  and angled portion  30  connects to a respective end of connecting portion  28 , while the other end  34  of angled portion  30  attaches to upright portion  22 . The resulting structure resembles the outline of a right triangle, with angled portion  30  constituting the hypotenuse.  
           [0005]    [0005]FIG. 1 details the protruding nature of braces  10 . Such braces  10  frequently extend outward several feet from side walls  18  on both sides of pool  14 , increasing the surface area of the lawn required for installing the pool. This increased surface area can cause difficulties in installing pools in areas subject to covenants or zoning regulations, as insufficient land may remain post-installation to meet setback and other legal or contractual requirements. Braces  10  may also inhibit lawn maintenance adjacent pool  14  and, to some, may detract from the aesthetic appeal of the pool itself. The three-piece structure of each brace  10  additionally increases its associated manufacturing and installing cost, while supporting less than the entire vertical height of a side wall  18 .  
         SUMMARY OF THE INVENTION  
         [0006]    The present invention, by contrast, provides a support system intended to resolve these issues. Particularly suited for vessels such as elongated above-ground pools, the support system includes a set of, typically, one-piece buttresses adapted to support the entire vertical height of one or each of a series of side walls. The flared design of the buttress, furthermore, matches the support it provides the side wall to the outward water pressure present along its height for enhanced reliability, permitting use of fewer buttresses than the number of existing braces that would otherwise be necessary. The one-piece design of the buttress further eliminates some of the manufacturing and installation costs associated with existing braces, while its sleek appearance is more likely to please discerning observers.  
           [0007]    The diminished footprint of the innovative buttress additionally reduces the surface area required for its corresponding pool. Setback and similar requirements thus pose fewer problems than with existing pools, permitting pools incorporating the present invention to be located in smaller (especially narrower) lawns. Consequently, more residential customers in densely-populated areas are able to situate these pools in the lawn space available to them, increasing the market for the pools beyond that existing today. Abolishing the open areas between the angled portions of current braces and the ground additionally avoids many of the difficulties associated with providing lawn care in those areas.  
           [0008]    In some embodiments of the invention, each buttress is a unitary structure whose height approximates that of the side wall or walls of its associated pool. At least one surface of the buttress contacts the side wall along substantially its entire height, supporting the height of the wall continuously against the outward pressure exerted when the pool is filled with water. Because the buttress defined by these embodiments flares along its height it assumes, in side elevational view, the general form of a truncated, solid triangle. Embodiments of the buttress further comprise notched sections to retain the bottom rim of the pool—and therefore help retain the side walls—in place.  
           [0009]    Additionally included in some support systems of the present invention may be elongated cross-members spanning the width of the pool. Often called “omegas”because of their cross-sectional appearance, the cross-members, when present, are buried so that only their upper surfaces are above the ground. Buttresses on each side of the pool may be bolted or otherwise attached to the upper surfaces to retain them in position relative to the ground. Protruding from the upper surface of a cross-member adjacent its ends are one or more tabs, which in use fit into slots in the bottom rim of the pool to maintain its position. The buttresses, side walls, bottom rim, and cross-members thus can interact to preserve the position and structure of the pool relative to the ground. Alternatively, the buttresses may extend below ground level and be bolted, interlocked, or otherwise connected or fitted to the cross-members.  
           [0010]    It is therefore an object of the present invention to provide a system for supporting a vessel designed to be filled with water or similar fluid.  
           [0011]    It is also an object of the present invention to provide a system including one or more buttresses for supporting the side wall or walls of an above-ground swimming pool.  
           [0012]    It is a further object of the present invention to provide a system in which a buttress supports a wall of a pool substantially continuously along the height of the wall.  
           [0013]    It is another object of the present invention to provide a system for supporting pool walls in which the supporting structures extend only minimally beyond the exteriors of the walls.  
           [0014]    It is an additional object of the present invention to provide a system, including one or more buttresses, for supporting a vessel such as an above-ground pool, in which the buttresses comprise notched sections to retain the bottom rim of the pool in position.  
           [0015]    It is yet another object of the present invention to provide a system for supporting an above-ground swimming pool in which buttresses, side walls, the bottom rim, and cross-members interact to maintain the position and structure of the pool relative to the ground. 
       
    
    
       [0016]    Other objects, features, and advantages of the present invention will be apparent with reference to the drawings and remainder of the text of this application.  
       BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]    [0017]FIG. 1 is a perspective view of an oval pool having an existing set of braces.  
         [0018]    [0018]FIG. 2 is a perspective view of an oval pool utilizing a support system of the present invention.  
         [0019]    [0019]FIG. 3 is a side elevational view of a portion of the pool and of a buttress of the support system of FIG. 2.  
         [0020]    [0020]FIG. 4 is a top plan view of the buttress of FIG. 3.  
         [0021]    [0021]FIG. 5 is a side elevational view of the buttress of FIG. 3 together with a surface of a cross-member of the support system of the present invention.  
         [0022]    [0022]FIG. 6 is a perspective view of a portion of the cross-member of FIG. 5.  
         [0023]    [0023]FIG. 7 is a (nominally) front elevational view of the buttress of FIG. 3 together with portions of the cross-member of FIG. 5 and the bottom rim of the pool of FIG. 2.  
         [0024]    [0024]FIG. 8 is a perspective view of an alternative buttress of the present invention.  
         [0025]    FIGS.  9 A-C are (nominally) front elevational views of yet alternative buttresses and cross-members for use as support systems of the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0026]    FIGS.  2 - 5  and  7  illustrate buttresses  38  of the present invention. As shown in FIG. 2, buttresses  38  may be used in connection with pool  14 ′ instead of braces  10 . Doing so can diminish significantly the surface area required for installation of pool  14 ′, permitting pool  14 ′ to be positioned in areas inadequate for placement of pool  14 . As noted earlier, setback and similar requirements additionally pose fewer problems for pool  14 ′ because of its smaller overall size.  
         [0027]    [0027]FIGS. 2 and 3 detail typical locations of buttresses  38  in connection with pool  14 ′. Illustrated in FIG. 2 is a set of buttresses  38  spaced along side  42  of (generally) oval pool  14 ′. Although not shown in FIG. 2, a similar set of buttresses  38  may be spaced along opposite side  46  of pool  14  ′. Because pool  14 ′ is oval, sides  42  and  46  are elongated relative to ends  50  and  54  and subject to greater stresses caused by the pressure of water W within the pool  14 ′.  
         [0028]    This pressure within pool  14 ′ additionally is greatest at bottom  26  of side wall  18  (adjacent ground G) and decreases toward the corresponding top  58  of the wall  18 . To support the entirety of height H of side wall  18 , the above-ground height of buttresses  38  may be substantially similar or identical to height H and, as shown in FIG. 3, most or all of their surfaces  62 A and  62 B (see FIGS. 4 and 7) may contact the side wall  18 . To match more closely the support provided side wall  18  to the pressure of water W as a function of height H, buttresses  38  additionally may be flared in depth as illustrated in FIGS. 2 and 3. Such flaring results in buttress  38  having its minimum depth D 1  at its top  66  and its maximum depth D 2  at its bottom  70  (also adjacent ground G), with the depth increasing substantially continuously between top  66  and bottom  70 . Buttress  38  thus resembles, in the side elevational view shown in FIG. 3, a right triangle.  
         [0029]    Unlike brace  10 , however, buttress  38  of FIG. 3 has solid sides  74 A and  74 B, a solid face  78 , and is truncated at top  66 . Surfaces  62 A and  62 B, moreover, function as flanges of buttress  38 . The result is a unitary structure for buttress  38  that both provides greater and more uniform and continuous support for side wall  18  and has a sleeker profile than braces  10 . Furthermore, for some embodiments of buttress  38 , maximum depth D 2  does not exceed ten inches, an amount significantly less than the distance (typically thirty-six inches) from pool  14  that braces  10  protrude. Other dimensions of an exemplary buttress  38  include height between approximately forty-two and sixty inches, width of approximately four inches, and a minimum depth D 1  of approximately two to four inches. Buttress  38  is usually made of metal such as galvanized steel but may be manufactured of other materials when necessary or appropriate. The face  78 , sides  74 A and  74 B, and surfaces  62 A and  62 B of buttress  38  additionally need not be integrally formed, although so forming them may avoid reducing the strength of the overall structure. Surfaces  62 A and  62 B also need not necessarily be formed at substantially right angles to respective sides  74 A and  74 B as shown in FIG. 4.  
         [0030]    [0030]FIG. 5 illustrates notched section  82  of buttress  38 . In use, buttress  38  may be connected (by bolts or other suitable means) to a cross-member  86  spanning the width of pool  14 ′. Such a cross-member  86  is shown in FIG. 6 and is buried in ground G so that only upper surface  90  is visible, and it is to this surface  90  that buttress  38  connects. Attaching buttress  38  to cross-member  86  in this manner thus retains the buttress  38  in position relative to ground G. Once buttress  38  is positioned, rim  94  (see FIG. 7) may be fitted into section  82  to assist in fixing its placement relative to the ground G. Slots of rim  94  additionally may receive tabs  98  protruding from upper surface  90  of cross-member  86  to complete its positioning. Side wall  18  may then be fitted into rim  94  in conventional fashion to retain it in place. Those skilled in the art will thus recognize that buttresses  38 , side wall  18 , rim  94 , and cross-members  86  of the present invention may be designed if desired to interact appropriately to preserve the position and structure of pool  14 ′ relative to the ground G.  
         [0031]    Shown in FIG. 8 is an alternative buttress  38 ′. Unlike corresponding components of buttress  38 , face  78 ′ of buttress  38 ′ is curved, and surfaces  62 A′ and  62 B′ are formed at acute angles to respective sides  74 A′ and  74 B′. Buttress  38 ′ additionally extends beyond notched section  82 ′ to terminate at lower edge  102 , which in use is buried underground.  
         [0032]    FIGS.  9 A-C detail alternate cross-members  106 A-C. Like upper surface  90  of cross-member  86 , upper surfaces  110  of cross-members  106 A-C are at or near the level of ground G. Similar to buttress  38 ′, furthermore, buttresses  114 A-C extend so that lower edges  118 A-C are buried underground. In the buttress  114 A of FIG. 9A, lower edges  118 A are bent to form flanges  122 , which include apertures in which bolts  126  or other fasteners may be placed. Horizontal sections  130  additionally include apertures for receiving bolts  126 , thereby permitting buttress  114 A to be fastened to cross-member  106 A. By connecting buttress  114 A to horizontal sections  130  rather than vertical sections  134  of cross-member  106 A, bolts  126  are subjected to reduced shear stresses optionally excavating ground G to pour a concrete or other base C beneath horizontal section  130  may enhance the ability of buttress  114 A to support a pool.  
         [0033]    Cross-members  106 B and  106 C instead may include slots  138  or recessed segments  142  for receiving pins or tabs  146  of buttresses  114 B or  114 C. Such slots  138  or recesses formed by segments  142  effectively retain buttresses  114 B or  114 C in position relative to respective cross-members  106 B or  106 C by engaging, or interlocking with, tabs  146  below ground G. Although lower edge  118 B is flanged and lower edge  118 C is not, such edges  118 B-C may be interchanged as necessary or desired. In any case, the result is a relatively secure positioning of a buttress  38 ′,  114 A,  114 B, or  114 C vis-a-vis a cross-member  106 A,  106 B, or  106 C by connecting them underground.  
         [0034]    The foregoing is provided for purposes of illustrating, explaining, and describing embodiments of the present invention. Modifications and adaptations to these embodiments will be apparent to those skilled in the art and may be made without departing from the scope or spirit of the invention.

Summary:
Support systems for vessels such as above-ground swimming pools are disclosed. Each system may include one or more buttresses adapted to support substantially the entire vertical height of the side wall or each of a series of side walls of the pool. The buttresses, which flare along their lengths, closely match the support they provide each side wall to the outward water pressure present-along its height for enhanced reliability. The diminished space required for installation of the disclosed buttresses reduces the surface area required for their associated pool.