Note: Descriptions are shown in the official language in which they were submitted.
CA 02496090 2005-02-08
SANDBAG WALL SYSTEM WITH UNTIED SANDBAGS
Technical Field of the Invention
The invention pertains to sandbag wall systems for use in erosion
control, flood protection, coastal pro~:ection, slope stabilization and
similar applications.
Background of the Invention
In the art of erosion control, flood pr~~tection, coastal protection, slope
stabilization and the like, it is known to build stable and effective walls
of sandbags, preferably using interco:lnecting plates to connect the bags
together and stabilize the wall. See, 'For example, international patent
publication WO 00/61880 (Kim), datt:d October 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 pro~ride a sandbag configuration in
which the bags could be filled to theix top edge, thus holding more fill
material.
Summary of the Invention
The invention provides a wall-buildin;; 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 th~~ second bag being adjacent to the
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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.
S
These wall-building units, which hold more fill material than a conven-
tional 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 sf;eds for vegetation. The term
"sandbag" 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 "v~~all" as used herein in relation to
structures made of wall-building units includes any array of wall-build-
ing 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 barrier, landscaping, and for similar
applications .
Brief Description of the Drawings
Figure 1 is a perspective view of a prior art sandbag;
Figure 2 is a perspective view of a wall-building unit according to the
invention comprising two bags;
Figure 3 is a further embodiment of the wall-building unit;
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Figure 4 is an end view on the line 2-2 of Figure 2; and
Figure 5 is an end view of a further f;mbodiment 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
Figure 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 Figures 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 longi~udinal 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.
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Referring to the embodiment of Figure 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 t:op 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.
Figure 5 shows an embodiment of thf; 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 farmed by two sheets of material
(for example geotextile) sewn together along longitudinal seam 136 and
their bottom end seam. The outer an~3 inner walls are otherwise unat-
tached, so a pocket or space 142 is farmed 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 12s;. A pre-seeded sheet 146 can
likewise be placed in space 138 between the inner bag and the outer bag
in the embodiments of Figures 2-4.
To construct a retaining wall using the: wall-building units of Figures 2
to 5, the wall-building units are arran;;ed in the same ways as are the
prior art sandbags of Figure 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 Figure 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.
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As will be apparent to those skilled in the art in the light of the forego-
ing 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.
