EXPLOSION RESISTANT WASTE CONTAINER

Abstract

An explosion resistant waste container includes an outer open-topped container and an inner open-topped container with a space therebetween. The outer and inner container are made from portions of compression cylinder members. The space between the two containers is filled with sand.

Description

TECHNICAL FIELD

The present invention relates generally to waste containers, and more particularly to waste containers that can withstand explosive forces and safely direct these forces away from surrounding persons and property.

BACKGROUND OF THE INVENTION

Waste containers are well known. These containers may take a variety of forms for use in a variety of places.

In particular, large waste containers are commonly used in places frequented by the public. For example, these waste containers may be found in airports, government buildings, hospitals, schools, street corners of highly populated cities, and at various public events.

A serious problem concerning these waste containers is that a bomb can be surreptitiously hidden therein and subsequently detonated for the purpose of harming surrounding persons or property. Current waste containers may not be sufficiently strong to withstand the explosions. For instance, current waste containers may either disintegrate or fragment into airborne shards. As a result, many persons within a blast perimeter of the bomb may suffer serious bodily injury or death. Of course, valuables and other property within the immediate area may also be damaged or destroyed.

One type of improved waste container is disclosed in Publication No. U.S. 2003/0213802 A1 published on Nov. 20, 2003, which is the publication of U.S. patent application Ser. No. 10/150,605, filed on May 17, 2002. Although that waste container is satisfactory and effectively reduces the danger of explosions, there still is a need for different embodiments.

Therefore, a further need exists for improved waste containers that maintain their integrity when subjected to explosions and direct explosive forces away from surrounding persons and property.

SUMMARY OF THE INVENTION

The present invention provides an explosion resistant waste container. The waste container includes an outer open-topped container and an inner open-topped container disposed within the outer-open topped container. The space between the two containers can be filled with a rigid or compressible material. The outer open-topped container is made of sufficiently strong materials, for withstanding much of the force of an explosion. In one embodiment, the inner open-topped container is made from a piece or formed pieces of material, such as a rolled coil of steel. In another embodiment, the inner and outer containers are made from portions of cylindrical members of a type and specification constructed to withstand substantial internal pressures and forces.

If a compressible material, such as a foam material, is disposed within the space between the outer container and the inner container, it will allow the inner cylinder to expand if an explosive device is discharged within it. This could help mitigate the damaging force of the explosion. Also, a rigid material, such as concrete, or a semi-rigid material, such as sand, could be utilized in the space and provide a heavier and stronger assembly.

One advantage of the present invention is that it can direct explosive forces away from surrounding persons and property. Another advantage of the present invention is that it can function in a normal manner as a waste receptacle for receiving and storing waste therein.

Other advantages of the present invention will become apparent when viewed in light of the detailed description of the preferred embodiments when taken in conjunction with the attached drawings and appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a perspective view of an explosion resistant waste container according to one embodiment of the present invention.

FIG. 1B is a perspective view of a funnel lid according to an embodiment of the present invention.

FIG. 2A is a perspective view of an inner open-topped container of an explosion resistant waste container according to an embodiment of the present invention.

FIG. 2B is a plan view of a first flat sheet of metal used for forming the inner open-topped container, according to an embodiment of the present invention.

FIG. 2C is a perspective view of a bottom inner plate used for forming the inner open-topped container, according to an embodiment of the present invention.

FIG. 3A is a perspective view of an outer open-topped container of an explosion resistant waste container according to an embodiment of the present invention.

FIG. 3B is a plan view of a second flat sheet of metal used for forming the outer open-topped container, according to an embodiment of the present invention.

FIG. 3C is a perspective view of a bottom outer plate used for forming the outer open-topped container, according to an embodiment of the present invention.

FIG. 4 is a top view of the explosion resistant waste container as shown in FIG. 1A, taken along line 4-4.

FIG. 5 is a perspective view of an explosion resistant waste container being subjected to an explosion.

FIG. 6 is a flowchart showing a method for manufacturing an explosion resistant waste container according to an embodiment of the present invention.

FIG. 7 is a cross-sectional view of a step in the manufacturing process of an explosion resistant waste container in accordance with an embodiment of the present invention.

FIG. 8 is a perspective view of another embodiment of the invention.

FIG. 9 is another view of the waste container shown in FIG. 8, but with the cover or top in an open position.

FIG. 10 is a cross-sectional view of the waste container shown in FIGS. 8 and 9.

FIG. 11 is a plan view of a flat sheet of material used to make a portion of the waste container shown in FIGS. 8 and 9.

FIG. 12 illustrates a spacer member preferably used with the embodiment of the invention shown in FIGS. 8 and 9.

FIG. 13 illustrates an alternate spacer member.

FIG. 14 illustrates a compression cylinder of a type for use with the present invention.

FIG. 15 illustrates another alternate explosion resistant waste container.

FIG. 16 illustrates still another alternate explosion resistant waste container.

DESCRIPTION OF THE PREFERRED EMBODIMENT

In the following figures, the same reference numerals are used to identify the same components in the various views.

Referring to FIG. 1A, there is generally shown an explosion resistant waste container 10 according to one embodiment of the present invention. The waste container 10 is normally used for receiving and storing waste. In addition, the waste container 10 can shield surrounding persons and property from explosions originating therein.

The waste container 10 generally includes an inner open-topped container 12, an intermediate material 14, and an outer open-topped container 16.

The waste container 10 also preferably includes a lid 18 (“cover” or “top”) that is releasably attached to a lip portion 40 of the inner open-topped container or a rim portion 42 of the outer open-topped container 16. The lid 18 may be a hood (as shown in FIG. 1A), a funnel (as shown in FIG. 1B), or any other suitably shaped cover. The lid 18 preferably is made of a heavy-duty polyethylene. However, it is obvious that the lid 18 may be made of metal or other suitable materials.

The lid 18 also can be attached to the reinforcing material 14 of the waste container 10, such as by a tether 44. The tether 44 can be a nylon strap having a first end embedded within the reinforcing material 14 and a second end attached to the lid 18 (as shown in FIG. 1A). Of course, the first end of the tether 44 may instead be attached to either the inner container 12 or the outer container 16 as desired. Furthermore, the second end of the tether 44 may be attached to either an outer portion of the lid (as shown in FIG. 1A) or an inside portion of the lid 18. Rivets or other suitable fasteners may be used to attach the ends of the tether 44 to their respective surfaces.

Referring now to FIG. 2A, there is shown an inner open-topped container 12 of the waste container 10 according to an embodiment of the present invention. The inner container 12 is made of a sufficiently strong material that can be subjected to an explosion without being destroyed or broken apart. Preferably, this material is 11 gauge steel coated with a powder for preventing rust or corrosion that may weaken the strength of the steel. The 11 gauge steel can provide sufficient strength without adding undesired weight to the waste container 10.

Of course, the inner container 12 may be made of various other suitable materials that are strong enough for withstanding explosions. For example, the inner open-topped container may be made of a heavier 7 gauge steel. Also, the container 12 may be made of a nylon or plastic material reinforced with a synthetic fiber, such as KEVLAR.

The inner container 12 preferably includes a cylinder 20 and a bottom plate 22 which is attached at one or more locations to the lower end of the cylinder 20. The cylinder 20 can be formed by rolling a first flat metal sheet 24 (as shown in FIG. 2B) into a coil with overlapping ends 26. The two ends 26A and 26B of the sheet member 24 are positioned so that they tightly overlap one another (as shown in the drawings) creating a slip joint.

Although FIG. 2A illustrates a circular cross-section of the container 12, it will be obvious to one skilled in the art that the cross-section of inner container 12 may be shaped otherwise. For example, the inner container can have multiple sides, or be made of a plurality of sheets or sections welded or otherwise secured together so long as the inner container 12 has sufficient thickness and strength for withstanding the force of an explosion, and has two edges or a joint which allows expansion if subjected to an explosion.

The bottom inner plate 22 (as shown in FIG. 2C) is preferably attached to the lower end of the cylinder 20 at one or more locations. Preferably, it is welded at least at one location along the bottom edge of the cylinder at location 25 which is generally opposite to the slip joint seam 26. The shape of the bottom plate 22 preferably corresponds to the cross-sectional shape of the inner container. Also, the bottom plate should be attached to the inner container only at a sufficient number of locations (or only along one or more edges) to securely hold the two components together, but not restrict expansion of the walls of the container as indicated above if subjected to the force of an explosion.

As best shown in FIG. 1A, the inner container 12 has a lip portion 40 extending upward beyond the reinforcing material 14. A user may wrap a top end of a trash bag around the lip portion 40 for the purpose of securing the trash bag to the container 10. Also, a portion of the lid 18 may be used to pinch the trash bag against the lip portion 40 and assist in holding the trash bag in place.

Referring now to FIG. 3A, there is shown an outer open-topped container 16 of the waste container 10 according to one embodiment of the present invention. Similar to the inner open-topped container 12, the outer open-topped container is made of a material capable of withstanding the forces of an explosion without being destroyed or broken apart, and preferably without experiencing substantial deformation. This material preferably is 11 gauge steel coated with corrosion resistant powder and alternatively may be any other suitable material.

In one embodiment, the outer container preferably is formed by rolling a flat sheet of metal material 34 and then welding together the opposing ends forming a seam 36. In this embodiment, the outer container 16 comprises a cylinder 30 and a bottom plate 32 attached to the lower end of the outer cylinder 30. Once the opposing ends are welded together, the outer cylinder 30 may be re-rolled for providing an improved circular cross-section of the outer cylinder 30. Furthermore, re-rolling the outer cylinder 30 may smooth the outer seam 36 so as to provide a more pleasing aesthetic appearance.

As is known in the art, the outer cylinder 30 may not have a well formed circular diameter after rolling the sheet 34 only one time. In this regard, the outer cylinder may slightly bow radially outward along the seam 36 where the opposing ends of the sheet 34 are joined. Therefore, it may be necessary to re-roll the outer cylinder 20 a second time after welding the opposing ends together so as to allow for an improved circular cross-section.

It will also be obvious to one skilled in the art that the cross-section of the outer open-topped container 16 may be circular, non-circular, or multiple-sided as long as it has sufficient thickness and strength for withstanding the force of an explosion. In other embodiments, the outer container could be made of a plurality of flat plates (e.g. steel sheets) welded together, for example, in a square, hexagon, or octagon cross-sectional configuration.

It is also obvious that the cross-sections of the two containers 12, 16 could be different from each other, so long as sufficient space is left between them for an intermediate material 14. For example, the inner container could have a circular cross-section while the outer container could have a square or other polygon shaped cross-section, or vice versa.

The outer open-topped container 16 also includes a bottom plate 32 that is secured (e.g. welded) to a lower end portion of the cylinder 30. Obviously, the bottom plate 32 may be attached to the lower end portion by any conventional fastening method. The bottom plate 32 preferably has the same size and shape as the cross-section of the outer container.

The outer container 16 is sized for receiving the inner open-topped container 12 therein and leaving a space therebetween. The space between the surfaces of the outer open-topped container 16 and the surfaces of the inner open-topped container 12 can be provided by, for example, one or more positioning elements 28.

The positioning elements 28 can be a plurality of legs or spacer members extending from the first sheet of material 24 (as shown in FIGS. 2A and 2B). The positioning elements 28 may also be a variety of other suitable devices that provide the desired space between the containers 12, 16. For example, the positioning elements 28 may be a plurality of columns integrally formed as part of the bottom outer plate 22. Alternatively, the positioning elements 28 can simply be bricks, blocks, or any other suitable device that offsets the outer surface of the inner container 12 from the inner surface of the outer container 16. Although four leg members are shown in the drawings, it is understood that any number of leg members or spacers could be utilized.

The outer open-topped container 16 may also include an outer plurality of leg members 38 for positioning the waste container 10 in an upright position. Also, these leg members 38 elevate the waste container 10 so as to allow a person to slide a dolly or the like underneath the waste container 10 for transporting it from one location to another. These leg members 38 can be integrally formed as part of the outer cylinder 30. Alternatively, the leg members 38 can be integrally formed as part of the bottom outer plate 32. Of course, the leg members 38 may be coupled to other portions of the outer open-topped cylinder or even completely omitted. Although four members 38 are shown in the drawings, it is understood that any number of leg members 38 can be provided.

Referring now to FIG. 4, there is shown a top view of the waste container 10 of FIG. 1A, as taken along line 4-4. The inner open-topped container 12 is preferably placed within the outer open-topped container 16 such that the inner seam 26 of the inner open-topped container 12 is positioned offset or out-of-phase with the outer seam 36 of the outer open-topped container 16. Arranging the seams 26, 36 in this manner increases the strength of the container 10 thereby increasing the container's resistance to deformation or damage when subjected to an explosion. Preferably, the seams 26, 36 are offset 180 degrees from each other for providing optimal resistance to deformation. Of course, the seams 26, 36 may be offset from each other at other angles. Where either the container or outer container (or both) is made from two or more pieces or sheets of material joined together, it is preferable to orient and assemble the two containers such that none of the seams of the two containers are in radial alignment.

The waste container 10 further includes a material 14 disposed within the space between the inner open-topped container 12 and the outer open-topped container 16. The material 14 can be a compressible material, such as a foam material, and preferably fills or substantially fills the entire space between the inner container 12 and outer container 16. A compressible material allows the inner container to expand if an explosive device is discharged within the waste container. As the inner cylinder expands, the metal material 24, particularly at the slip joint 26, is forced into the foam material, leaving the outer cylinder intact. Of course, the intermediate material 14 may be composed of various other compressible materials which will allow the inner cylinder to expand as noted and therefore absorb the force of any explosive device.

The positioning element 28 preferably provides a clearance of two or more inches between the surfaces of the containers 12, 16. This clearance allows for a sufficient thickness of the compressible material 14. Obviously, the size of the space between the containers 12, 16 and the amount of material 14 may be varied as desired.

It is also possible to utilize reinforcing material, such as concrete, in the space between the two bottom plates 22 and 32. This adds additional weight to the container, which makes it harder for vandals to tip it over or move, and also adds additional strength and integrity to the container which could assist in resisting the force of an explosion. It is also possible to fill the entire space between the inner and outer containers with a non-compressible or semi-compressible material, such as concrete or sand.

FIG. 5 illustrates the waste container 10 being subjected to an explosion. When a bomb is detonated within the waste container 10, most of the explosive forces are directed upwardly and thus away from the surrounding persons and property within a horizontal perimeter of the container 10. The compressible material 14 is utilizd in the container, the material can help absorb some of the explosive force as the inner container expands due to the explosion. In this regard, the outer open-topped container 16 can maintain its shape and structural integrity.

The blast forces may destroy the lid 18 and propel objects within the container 10 relatively straight upward. However, the surrounding persons and property within the horizontal perimeter of the container are sufficiently protected from the explosion.

Referring now to FIG. 6, a flowchart shows a method for manufacturing an explosion resistant waste container 10 in accordance with an embodiment of the present invention. The method is initiated at step 50 and then immediately proceeds to step 52.

In step 52, the inner open-topped container 12 (as shown in FIG. 2) of the waste container 10 is formed. This step is preferably accomplished by first providing one or more metal sheets 24 (as shown in FIG. 2B) and then forming them into the inner container 20. A joint or seam between at least two sheet ends, such as opposing ends 26A and 26B of sheet 24, provide a tightly overlapping relationship forming a slip joint. Then, a bottom inner plate 22 (as shown in FIG. 2C) is welded at one or more locations to a lower end portion of the inner container 20. After forming the inner open-topped container 12, the sequence proceeds to step 54.

In step 54, an outer open-topped container 16 (as shown in FIG. 3A) of the waste container 10 is formed. One or more metal sheets, such as sheet 34, as shown in FIG. 3, is formed or rolled to provide an outer container 30. The opposing ends of the single sheet or plurality of sheets are welded together forming one or more outer seams, such as seam 36. If a round or cylindrically shaped outer container is formed, then the outer cylinder 30 can be re-rolled if necessary to smooth the outer seam 36 and provide the desired cross-section of the outer cylinder 30.

In a preferred embodiment, the inner container 12 can be welded at one or more locations to the bottom plate 32 before the bottom plate 32 is welded to the lower end portion of the outer cylinder 30.

Specifically, the inner container 12 is affixed to the bottom plate 32 with one or more positioning elements 28 placed therebetween. The positioning elements 28 provide the requisite clearance space between the inner container 12 and the outer container 16. The positioning elements 28 preferably comprise a plurality of legs integrally formed as part of the inner open-topped container 12. These legs could also be separately made and welded to the bottom outer plate 32.

Of course, the positioning elements 28 may be other suitable devices for providing a space between the bottom plates of the two containers 12, 16. For example, the positioning elements 28 could consist of a plurality of columns integrally formed as part of the bottom outer plate 32. Furthermore, the positioning elements 28 may simply be bricks or other materials placed between the bottom plates 22 and 32.

The bottom outer plate 32 is positioned within the outer container 16 so as to place the seams 26, 36 in the desired position offset from one another. These seams 26, 36 can be placed 180 degrees out-of-phase, but also may be positioned otherwise as desired. Once the seams 26, 36 are in the desired position, the bottom outer plate 32 is welded to the lower end portion of the outer cylinder 30.

After the outer open-topped container 16 is formed and the inner open-topped container 12 is positioned within the outer open-topped container 16, the sequence proceeds to step 56.

In step 56, material 14 is inserted into the space between the inner and outer containers. In one embodiment, this step is accomplished by simply positioning pieces of a foam material in the clearance space, or pouring an expandable liquid foam material into the space and allowing it to expand and fill out the clearance space. Also, as indicated above, the portion of the clearance space between the two bottom plates could be filled with a concrete material.

As shown in FIG. 7, in one embodiment, the inner open-topped container 12 and the outer open-topped container 16 are tilted at an angle, preferably about 45 degrees, while the material 14 is initially poured into the space between the inner open-topped container 12 and the outer open-topped container 16. Tilting both containers 12, 16 allows the material to fill in all spaces between the containers 12, 16. In particular, tilting the containers 12, 16 assures that the material will fill in the space between the bottom plate 22 of the inner container 12 and the bottom plate 32 of the outer container 16.

The containers 12, 16 are positioned in their upright positions when sufficient material has been poured into the space between them such that the material may begin to spill out of the waste container 10. Once the containers 12, 16 are in the upright position, the remainder of the space is filled with the material 14. Thereafter, the material is cured or allowed to harden so as to strengthen the integrity of the inner open-topped container 12.

Another embodiment of the present invention is shown in FIGS. 8 and 9 and indicated generally by the reference numeral 100. In FIG. 8, the explosion resistant waste container 100 is shown with the cover in the closed position, while in FIG. 9 the cover is shown in its open position.

In general, the waste container 100 includes an outer open topped container member 102, an inner open topped container member 104, and a cover member 106. In this embodiment, the outer container 102 has a substantially square or rectangular-shaped configuration. The shape of the outer container 102 is also shown in the cross-sectional view depicted in FIG. 10.

The inner container 104 is preferably substantially the same as inner cylindrical container 12 as described above with reference to FIGS. 1A and 2A. In this regard, the inner container 104 is preferably formed from a single piece of sheet metal material, such as steel, which is rolled into a cylindrical shape and formed with overlapping ends 104A and 104B.

Also, a bottom plate member (not shown) is positioned and attached to the lower end of the inner container 104, in the same manner as described above with reference to plate member 22.

It is also possible, of course, to provide an inner container having any cross-sectional shape, such as square, hexagonal, octagon, or the like, so long as at least one seam between the plates or parts is formed into a non-fixed overlapping joint.

The outer container member 102 can be formed of a plurality of plate members, such as four plate members, but preferably is formed from a pair of L-shaped or right-angle shaped members which are welded together along two seams. Each of the L-shaped members 110A and 110B can be formed from a single flat sheet of material, as shown in FIG. 11. In this regard, preferably the material is a metal material such as steel in order to provide the requisite durability and integrity to withstand the force of an explosion. Also, as shown in FIGS. 8, 9 and 11, a plurality of feet members 112 and 114 are formed on the flat plate members. When the flat plate members are formed into L-shaped components and two of the components 110A and 110B are welded together, the feet members elevate the outer open topped container 102 from the ground which permits ease of handling.

The cover member 106 is hingedly attached to the outer container 102 by an elongated hinge member 120. The opposite side of the cover member is preferably provided with a latch, or other locking mechanism (not shown) in order to secure the cover to the container and prevent unauthorized opening thereof.

The cover member 106 includes a lower cover member 122 and an outer or upper cover member 124. The lower cover member 122 includes an opening 126 which is situated such that persons discarding trash can insert the waste materials into the inner container 104.

The upper cover member 124 can have any particular size and shape but preferably is curved in a convex manner as shown. This provides a pleasing appearance to the waste container 100.

A plurality of frame members 130 can be positioned on the outside surfaces of the outer container 102. These frame members can be used for advertising and promotion posters, such as, for example, by businesses, communities, and the like.

The space 140 between the outer container 102 and inner container 104 can be filled with any conventional material or materials, such as concrete, sand, or a compressible material, such as a foam material. The material 142 is preferably the same as the material 14 described above with reference to FIGS. 1-7.

Corner spacer members 150 can be positioned in each of the four corners of the rectangularly shaped outer open topped container 102. The spacer members, one of which is shown by itself in FIG. 12, are used to fill in some of the excess space between the square and circular shapes of the two nested containers, and also add additional strength, durability, and integrity to the overall waste container structure. The corner spacer members 150 can be formed of a plurality of pieces of material secured or welded together forming a solid box-like structure 150, as shown in FIG. 12. In the alternative, the corner spacer members can merely be pieces of material secured or welded into the corners of the square-shaped container 102, as shown by the numeral 160 in FIG. 12.

Another preferred embodiment 200 of the present invention is shown in FIG. 15. This embodiment is made from two portions 210 and 220 of compression cylinders. A representative cylinder of this type 230 is shown in FIG. 14. Compression-type cylinders are commercially available for use, for example, in storing compressed gas for industrial or recreational use. They are typically made of metal material, such as steel, and manufactured to be durable and extremely strong for containing and maintaining large pressure forces. The explosion resistant waste container 200 is made from portions of two of such compression-type cylinders of different diameters and sizes. The container 230 is divided into two portions 230A and 230B, each of which can be used for one-half of a completed waste container, such as container 200.

The two container portions 210 and 220 are fitted together in the manner shown in FIG. 15 and described above with respective FIGS. 1-13. One or more supports 225 are positioned between the two portions 210 and 220 in order to space them apart.

The space 240 between the two portions 210 and 220 is filled with a material which assists in strengthening the completed waste container 200. In this embodiment, the preferred material for filling the space 240 is sand. It is believed that sand will aid in absorbing or lessening the force of an explosion which might take place within the inner portion 220.

FIG. 16 shows still another explosion resistant waste container 300 in accordance with the present invention. The inner container member 310 is a portion of a compression cylinder member similar to the container members 210 and 220 discussed above with respect to FIG. 15. The outer container member 320 has a square cross-sectional shape and is made from steel plate members in the same manner as the explosion resistant waste container members 102 with reference to FIGS. 8-10. The space 330 is filled with any of the materials described above, but preferably is filled with a sand material.

While particular embodiments of the invention have been shown and described, numerous variations and alternate embodiments will occur to those skilled in the art. Accordingly, it is intended that the invention be limited only in terms of the appended claims.

Claims

1. An explosion resistant waste container comprising: an outer open-topped container, an inner open-topped container placed within said outer open-topped container leaving a space therebetween, said inner container comprising a portion of a first compression cylinder member; and a sand material placed within said space between said outer open-topped container and said inner open-topped container.

2. The explosion resistant waste container of claim 1 further comprising: at least one positioning element that provides for said space between said outer container and said inner container.

3. The explosion resistant waste container of claim 1 wherein said inner and outer containers are both made from a high strength steel.

4. The explosion resistant waste container of claim 1 wherein said outer container comprises one or more sheets of metal material.

5. The explosion resistant waste container of claim 4 wherein said outer container has a square-shaped cross-section.

6. The explosion resistant waste container of claim 1 wherein said outer container comprises a portion of a second compression cylinder member.

7. The explosion resistant waste container of claim 1 wherein said inner open-topped container includes a lip extending slightly beyond said reinforcing material, said lip intended for securing at least one of a trash bag and a lid thereto.

8. The explosion resistant waste container of claim 1 further comprising: a lid releasably attached to at least one of said outer open-topped container and said inner open-topped container.

9. The explosion resistant waste container of claim 8 further comprising a tether fixedly coupling said lid to either said inner container or said outer container.

10. The explosion resistant waste container as described in claim 1 further comprising a cover member hingedly attached to said outer container.

11. A method for manufacturing an explosion resistant waste container, the method comprising the steps of: (a) forming an inner open-topped container, said inner container comprises a portion of a first compression cylinder member; (b) forming an outer open-topped container sized to receive said inner open-topped container leaving a space therebetween, (c) positioning said inner open-topped container within said outer open-topped container leaving a space therebetween; and (d) filling said space with a sand material.

12. The method of claim 11 wherein positioning said inner open-topped container within said outer open-topped container comprises positioning such that a lip of said inner open-topped container extends slightly above the top edge of said outer open-topped container.

13. The method of claim 11 wherein said outer container comprises a portion of a second compression cylinder member.

14. The method of claim 11 wherein said outer container comprises one or more sheets of metal material.

15. The method of claim 14 wherein said outer container comprises a square-shaped cross-section.

16. The method of claim 11 further comprising attaching a cover member to one of said inner and outer containers.