Liquid containment pool wall using polymer sheeting

Abstract

A liquid containment vessel or pool having a wall constructed of thermoplastic polymers. Most pool walls are manufactured from steel or aluminum which are prone to deformation and corrosion. Polymer sheets or banding can be used to replace customary pool walls, offering a tough, strong, lightweight, corrosion resistant and easily installed material that can be manufactured from recycled plastics. When oriented, laminated, woven, corrugated, or layered, the strength of the polymer sheeting or banding increases further, allowing the present invention to be adapted for use in a variety of applications.

Claims

1. A liquid containment vessel comprising: (a) a vessel base having a perimeter; (b) a rigid polymeric containment wall composed entirely of oriented polymeric sheet material and having an exposed exterior surface and an interior surface, said containment wall being secured about an entirety of the perimeter of the vessel base to form the liquid containment vessel; (c) a water-retaining liner disposed within the containment wall; and (d) a support frame, said support frame encasing and reinforcing the exposed exterior surface of the containment wall.

2. The liquid containment vessel of claim 1, wherein said oriented polymeric sheet material is made from oriented polyethylene terephthalate (PET).

3. The liquid containment vessel of claim 1, wherein said oriented polymeric sheet material is made from oriented polystyrene.

4. The liquid containment vessel of claim 1, wherein said oriented polymeric sheet material is made from oriented polypropylene.

5. The liquid containment vessel of claim 1, wherein said oriented polymeric sheet material is made from oriented polyethylene.

6. The liquid containment vessel of claim 1, wherein said oriented polymeric sheet material is corrugated.

7. The liquid containment vessel of claim 1, wherein said oriented polymeric sheet material is installed in concentric layers within the vessel base.

8. The liquid containment vessel of claim 1, wherein said oriented polymeric sheet material is installed in multiple single layers within the vessel base.

9. The liquid containment vessel of claim 1, wherein said containment wall is comprised of multiple plies of said oriented polymeric sheet material that have been laminated to form a rigid polymeric sheet.

10. The liquid containment vessel of claim 1, wherein said containment wall is comprised of multiple strips of said oriented polymeric sheet material that have been laminated to form a rigid polymeric sheet.

11. The liquid containment vessel of claim 1, wherein said containment wall is comprised of multiple strips of said oriented polymeric sheet material that have been woven to form a rigid polymeric sheet.

12. The liquid containment vessel of claim 1, wherein one or more bands of oriented polymer encircle the containment wall on the exposed exterior surface.

13. The liquid containment vessel of claim 1, wherein one or more bands of oriented polymer encircle the containment wall on the interior surface.

14. The liquid containment vessel of claim 1, wherein one or more layers of foil are laminated to the rigid containment wall.

15. The liquid containment vessel of claim 1, wherein one or more layers of woven or non-woven mesh are laminated to the rigid containment wall, the mesh selected from the group consisting of stainless steel, fiberglass, polymer, basalt fiber or carbon fiber.

16. The liquid containment vessel of claim 1, wherein the containment wall is coated with a material selected from the group consisting of ink, paint, varnish or decorative webbing.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) FIG. 1 provides a perspective view of a standard liquid containment vessel.

(2) FIG. 2 provides a perspective view of the polymer pool wall in a coiled form that has been made from multiple strips of material.

(3) FIG. 3A provides a perspective view of a plurality of oriented polymer strips encircling the exterior surface of the containment wall to provide reinforcement.

(4) FIG. 3B provides a perspective view of a multiple layers of oriented polymer strips encircling the exterior surface of the containment wall on a bias to provide reinforcement.

(5) FIG. 4A provides a top view of the coiled polymer sheeting.

(6) FIG. 4B provides a perspective view of a spiral installation of the polymer sheeting on the pool base

(7) FIG. 5A provides a side view of the lamination process

(8) FIG. 5B provides a side view of the final laminated product

(9) FIG. 6A is a side view of a pressure or impact point on a non-oriented polymer sheet

(10) FIG. 6B is a side view of a pressure or impact point on an oriented and laminated polymer sheet

(11) FIG. 7 provides a perspective view of the corrugation process

REFERENCE NUMERALS

(12) 5 Containment Wall 10 Support Frame 15 Hydrostatic Pressure 20 Vessel Base 25 Oriented Polymer Sheeting 30 Laminate Material 35 Adhesive 40 Laminating Pressure Rolls 45 Finished Laminated Material 50 Corrugating Rolls 55 Finished Corrugated Material 60 Coiled Material for Installation 65 Exposed Seam 70 Pressure or Impact Point 75 Waterproof Liner 80 Oriented Polymer Reinforcing Bands

DETAILED DESCRIPTION OF THE INVENTION

(13) Referring now to FIG. 1, a typical pool or liquid containment vessel is comprised of a containment wall 5 reinforced by a support frame 10 and resting on a vessel base 20. A water-retaining liner or membrane (not shown) may be placed over the containment wall 5 and vessel base 20 to create a water tight barrier.

(14) Liquid within the containment vessel exerts hydrostatic pressure 15 on the containment wall 5 as shown in FIG. 1; this pressure increases proportionally with the depth from the water surface. Pressure applied from motion within the pool such as diving, wave action and hydraulic shock can exceed the static water column pressure by several orders of magnitude. Consequently, the containment wall 5 must be made of a material having sufficient tensile strength, burst strength and creep resistance to accommodate these forces.

(15) The preferred embodiment is comprised of a containment wall 5 constructed from at least one sheet of rigid oriented polymer 25 such as PET. The plurality of chains within the material may be oriented axially or biaxially through conventional manufacturing means. The oriented polymer should be mechanically drawn at a draw ratio between 2:1 and 6:1 to achieve the material properties required for this application. The direction of orientation may also be adjusted to achieve a material with the desired burst strength, creep resistance, tensile strength, and toughness. Thickness of the polymer sheet may also be modified to improve these material properties.

(16) In another embodiment, single or multiple sheets or layers of non-oriented polymer pool wall may be used provided that the material has the requisite thickness, layering or positioning to withstand at least 1.25 times the static water column pressure exerted on a liquid containment vessel having a sixty inch depth.

(17) The containment wall 5 may alternatively may be formed by arranging multiple smaller strips of oriented polymer 25 and fusing them to each other or to one or more plies of polymer to form a sheet of the desired size as shown in FIG. 2. These materials may be fused by any common manufacturing method such as sonic or laser welding.

(18) In another embodiment, the containment wall 5 may be comprised of multiple smaller strips of oriented polymer 25 that are woven together to form a sheet of material.

(19) In yet another embodiment, one or more oriented polymer reinforcing bands 80 may be added to the containment wall 5 as shown in FIGS. 3A and 3B. These bands may encircle the exterior of the containment wall 5 much like hoops on a barrel to increase the strength of the containment vessel. Alternatively, the bands 80 may be affixed to the interior of the containment wall 5. The bands 80 may be secured to the containment wall 5 by any number of means including but not limited to plastic welding techniques, adhesive application or the use of mechanical fasteners.

(20) The bands 80, if used, will ideally be placed substantially parallel to one another and they may, but need not be, placed such that they are substantially parallel to the ground as shown in FIG. 3A. Multiple layers of banding may be used as shown in FIG. 3B and oriented in different directions. The bands 80 may also be woven together to further enhance their reinforcing strength. The spacing and widths of the bands 80 may vary based on the strength requirements for the particular application. The cross-sectional profile of the band may take any one of a number of shapes including but not limited to rectangular or bell-shaped profiles. It should be noted that the use of bands 80 may eliminate the need for a support frame 10 in applications requiring minimal strength provided that the material properties of the oriented polymer sheeting 25 and bands 80 are suited to the forces that will be exerted on the liquid containment vessel.

(21) Referring now to FIGS. 4A and 4B, the containment wall 5 is ideally manufactured in rolls or coils, allowing for easy installation. The containment wall 5 is unwound from the coil 60 and one or more overlapping sheets are placed the vessel base 20 to construct the containment wall 5. Concentric layering of containment wall 5 material will further strengthen the wall, offering increased impact resistance, creep resistance and durability. Because the seams are not exposed there are fewer points of failure in the containment wall 5. The single exposed seam 65 will be located on the exterior of the concentric layers. This seam may be fastened by any method or means that fixes the pool wall in a secure position.

(22) Polymeric sheet material may be used alone or in combination with a secondary sheet material create the containment wall 5 to enhance UV resistance, creep resistance, impact resistance and tensile strength. Additionally, decorative coatings, ink, paint, varnish or printed webbing may be applied to enhance the appearance and durability of the pool wall. The polymeric sheet material may be laminated or affixed to one or more layers of metallic foil, mesh, or plastic. Adhesive 35 may be introduced between the polymeric sheet material 25 and the laminate material 30 and be routed through pressure rolls 40 to create a finished laminate material 45 as shown in FIGS. 5A and 5B. The addition of one or more of these layers will increase the tensile strength and impact resistance of the pool wall. Similar means may be used to adhere multiple layers of polymer sheeting to enhance the strength of the containment wall 5.

(23) Mesh, if used, may be woven or non-woven and made out of any suitable material such as stainless steel, fiberglass, polymers, basalt fiber or carbon fiber. Laminated sheets of this nature are known to enhance material properties and will protect the containment wall 5 from tearing, ruptures, bursting and collapse. See FIG. 6A illustrating a pressure or impact point 70 penetrating a polymer sheet 75. FIG. 6B depicts oriented polymer sheeting 25 having impact resistant sufficient to prevent the pressure or impact point 70 from piercing the laminate material 30.

(24) Polymer or laminated polymer sheets may be corrugated using corrugating rolls 50 having a wave-like, square-edge, semi-circular or similar alternating shape, provided that such corrugations do not create an accordion effect on the material. See FIG. 7. Corrugations are commonly used in steel and are known for increasing the compressive strength of the base sheet material. Corrugations will similarly increase the tensile strength of polymer and laminated polymer sheets and will provide dimension to the sheet thickness, increasing its stiffness and allowing for easier installation. Ideally the corrugations in the material will be uniform and evenly spaced, allowing concentric layers of the pool wall to lock into one another. In addition, impact resistance will increase, the likelihood of warpage will decrease and a more durable containment wall will result in a corrugated containment wall 55.

(25) The polymeric sheet material used to create the containment wall 5 can be made using any one of a number of known plastic materials having sufficient strength to withstand at least 1.25 times the static water column pressure exerted on a liquid containment vessel having a sixty inch depth. The properties of PET make it a suitable plastic for use in this application. Because it is often made of recycled plastics, it is readily available, economical, and environmentally friendly; however, it should be recognized that a number of plastic materials may be used.

(26) While the above description contains many specifics, these should be considered exemplifications of one or more embodiments rather than limitations on the scope of the invention. As previously discussed, many variations are possible and the scope of the invention should not be restricted by the examples illustrated herein.