Sandbag Wall System with United Sandbags

Abstract

A wall-building unit for use in the construction of sandbag-type walls for erosion control, slope stabilization and similar applications comprises an inner bag filled with a fill material and an outer bag extending longitudinally over it so that the bottom of the outer bag is adjacent to and covers the open top edge of the inner bag. The wall-building unit holds more fill material than a conventional sandbag.

Description

TECHNICAL FIELD OF THE INVENTION

The invention pertains to sandbag wall systems for use in erosion control, flood protection, coastal protection, slope stabilization and similar applications.

BACKGROUND OF THE INVENTION

In the art of erosion control, flood protection, coastal protection, slope stabilization and the like, it is known to build stable and effective walls of sandbags, preferably using interconnecting plates to connect the bags together and stabilize the wall. See, for example, international patent publication WO 00/61880 (Kim), dated Oct. 19, 2000. The sandbags used in such systems have hitherto been conventional in design. In a conventional sandbag, the bag fill volume is limited by the fact that the top edge of the bag must be gathered together and tied in order to close the bag. It would be desirable to provide a sandbag configuration in which the bags could be filled to their top edge, thus holding more fill material.

SUMMARY OF THE INVENTION

The invention provides a wall-building unit for use in the construction of sandbag walls, each unit being made of two bags of the type used for sandbags. Each bag has a bag wall, a closed bottom and an open top edge. The first bag is substantially filled with a fill material. The second bag extends longitudinally over the first bag so that the bottom of the second bag is adjacent to and covers the open top of the first bag. In one embodiment, the second bag substantially covers the whole of the first bag, with the open top edge of the second bag being adjacent to the closed bottom of the first bag. In another embodiment, the second bag is shorter than the first bag and covers only part of the first bag, with the top edge of the second bag being positioned longitudinally between the open top edge and the closed bottom of the first bag.

These wall-building units, which hold more fill material than a conventional sandbag, are used in place of sandbags in the construction of retaining walls and erosion control structures.

In this specification, “fill material” means any material that is suitable for use in bags in the construction of walls, including sand, soil, gravel, dry mix concrete (which hardens after wetting and curing) and mixtures thereof, including fill material with seeds for vegetation. The term “sand-bag” as used in this specification means a bag containing any “fill material.” For further clarity, the term is not limited to a bag in which the fill material is sand. The term “wall” as used herein in relation to structures made of wall-building units includes any array of wall-building units that is suitable for the purpose of erosion control (for example along shorelines, riverbanks, etc.), flood control, retaining or stabilizing slopes or embankments, noise barriers, landscaping, and for similar applications.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a prior art sandbag;

FIG. 2 is a perspective view of a wall-building unit according to the invention comprising two bags;

FIG. 3 is a further embodiment of the wall-building unit;

FIG. 4 is an end view on the line 2-2 of FIG. 2; and

FIG. 5 is an end view of a further embodiment of the wall-building unit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The invention provides wall-building units comprising a combination of two bags. A prior art sandbag containing fill material is shown in FIG. 1. Prior art bag 100 has sewn bottom edge 102 and a side edge 104. It is tied closed at top edge 106 by means of a tie 108. In order to be able to fill the bag, the top edge is pulled together in a cinched configuration, as a result of which the bag cannot be filled to its top edge. The shoulders 110 reflect the reduction in fill volume resulting from this closing requirement.

In wall-building unit 120, shown in FIGS. 2 and 4, this loss in fill volume is eliminated. Inner bag 122 has a bag wall 124, a closed bottom 126 and an open top edge 128. The bag wall 124 is sewn closed along longitudinal edge 130. Outer bag 132 is of equivalent structure, with a bag wall 134 sewn along longitudinal edge 136, and a closed bottom 138 and an open top edge 140. The outer bag is positioned to extend longitudinally over the inner bag 122 so that its closed bottom 138 is adjacent to and covers the open top 128 of the inner bag 122. This leaves a space 139 between the two bags which, in practice, is small because the bags are tight fitting. It will be apparent that the inner bag 122 can be filled to its top edge with fill material, since the top edge is not cinched together to close, and the outer bag acts as a cover for the inner bag.

Referring to the embodiment of FIG. 3, it will be seen that the outer bag can be shorter in length than the inner bag. Outer bag 132A is shorter than the inner bag 122 so its top edge 140 is longitudinally intermediate the top edge 128 and the bottom 126 of the inner bag. Optionally, the top edge 140 can be attached to the wall of inner bag 122 by means of tape, velcro, etc.

FIG. 5 shows an embodiment of the wall-building unit 150 in which the outer bag is double walled. Outer bag 151 comprises an outer wall 152 and an inner wall 154. This is formed by two sheets of material (for example geotextile) sewn together along longitudinal seam 136 and their bottom end seam. The outer and inner walls are otherwise unattached, so a pocket or space 142 is formed between them. A pre-seeded sheet 146 is placed in this space, and comprises a sheet of absorbent material with plant seeds affixed or embedded therein. In use, the sheet 146 is positioned adjacent to the outer face of the wall to provide for the growth of vegetation on the wall face as the seeds geminate and their plant roots grow through the bag walls and into the fill material, for example soil, inside the inner bag 122. A pre-seeded sheet 146 can likewise be placed in space 138 between the inner bag and the outer bag in the embodiments of FIGS. 2-4.

To construct a retaining wall using the wall-building units of FIGS. 2 to 5, the wall-building units are arranged in the same ways as are the prior art sandbags of FIG. 1, arrangements that are well-known in the prior art. In addition to holding more fill than the prior art bag, since the wall-building units are effectively double-walled (or triple-walled for the embodiment of FIG. 5) they are very effective at holding fine fill material, such as clay soils that are commonly used as fill materials in wet areas. They are accordingly particularly useful for erosion control walls along shorelines, streams, etc.

As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifications are possible in the practice of this invention without departing from the scope thereof. Accordingly, the scope of the invention is to be construed in accordance with the substance defined by the following claims.

Claims

1. A wall-building unit for use in the construction of walls, comprising:

(a) a first bag having a bag wall, a closed bottom and an open top edge, said bag being substantially filled with a fill material; and

(b) a second bag having a bag wall, a closed bottom and an open top edge, said second bag extending longitudinally over said first bag such that said bottom of said second bag is adjacent to and covers said open top edge of said first bag.

2. A wall-building unit according to claim 1 wherein said open top edge of said second bag is adjacent to said closed bottom of said first bag.

3. A wall-building unit according to claim 1 said second bag has a length that is less than the length of said first bag and said open top edge of said second bag is positioned longitudinally between said open top edge and said closed bottom of said first bag.

4. A wall-building unit according to claim 1 further comprising a pre-seeded sheet between said first bag and said second bag.

5. A wall-building unit according to claim 1 wherein said bag wall of said second bag includes a pocket containing a pre-seeded sheet.

6. A wall comprising a plurality of courses of wall-building units according to claim 1.