Patent Publication Number: US-6991408-B2

Title: Soil replacement product

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is the first application filed for the present invention. 
     1. Technical Field 
     The present invention relates to low weight, non or minimal water retaining, non-biodegradable, soil replacement material contained in a properly constructed and fastened permeable bag. 
     2. Background of the Invention 
     Generally speaking, once existing soil is excavated from a construction site the decision to replace the soil is a difficult one usually requiring engineering analysis. The native soil is sometimes reused but this is generally undesirable if it is not consistent and free draining. In most instances the soil is replaced with imported natural aggregate materials such as stone, gravel, and sand. These imported materials are expensive to transport. They also are labour intensive to install and may require the use of large machinery. On difficult sites with existing structures the work could become very labour intensive. 
     A further limitation with existing soil replacement materials is the lack of long term drainage capacity, possibly increases in the weight compared to the soil replaced, and a lack of insulating ability. In colder climates, the possibility of structural damage due to freezing soil is also not fully eliminated. In the example where a contractor is undertaking a repair on a structure or wall, the contractor is required to combine different construction materials applied in a very strict and complicated manner to try and provide the engineering requirements to insure no further damage to the structure occurs. The drainage, loading and insulation requirements set out by the engineer will likely be expensive and difficult to accomplish. 
     It would be desirable to have a light weight, soil replacement product with a multitude of applications that would provide suitable drainage and reduced loading with some insulating characteristics. It should be easily conformable to the opening into which it is to be charged like other materials. It must also be easier to transport and install to reduce the labour and machinery costs associated with other materials. 
     A final important aspect of a soil replacement product is that it must not exhibit unusual or unacceptable characteristics as compared to other natural soil replacement materials. The multitude of applications for a soil replacement product will allow some flexibility, however the final analysis must insure a reasonable margin of safety is maintained when using any soil replacement product. 
     The present invention is focused upon satisfying the requirements which have been overlooked by prior art techniques by combining a lightweight soil replacement material in a permeable bag. This light weight, non water retaining, non-biodegradable product will provide good, long term water drainage, reduced loading on structures, insulating ability and will insure reasonable margin of safety characteristics similar to existing natural soil replacement materials. 
     SUMMARY OF THE INVENTION 
     One object of one embodiment of the present invention is to provide a lightweight, non water retaining, non-bio-degradable soil replacement product with an improved method of employing the same. 
     A further object of one embodiment of the present invention is to provide a lightweight, non or minimal water retaining, non-biodegradable soil replacement material contained in a permeable bag, comprising:
         a permeable and flexible container composed of a non biodegradable material capable of allowing the passage of moisture there through; and   a lightweight non water retaining, non biodegradable, material disposed within the bag, the bag when filled with the material providing a conformable, soil replacement material to fill an opening.       

     Advantageously, by providing the lightweight material in the bag, the overall weight of the product is significantly reduced compared to a similar volume of natural material, improving the ease of handling and reducing the loading characteristics of the volume of soil replaced. A particularly useful feature of the product is the ability to create air voids which most certainly will provide a resistance to heat flow. This will give the product an R-value or thermal resistance quality which is required in many construction and engineering situations. 
     In respect of the material of which the bag is made, the material which provides the requisite strength will depend on the environment in which the bag is used and can be selected by the designer. 
     A further object of one embodiment of the present invention is to provide a method of filling an area to be backfilled, comprising:
     providing a synthetic permeable and flexible bag composed of a non biodegradable material capable of allowing the passage of moisture there through;   providing light weight, non water retaining, non bio-degradable material disposed within the container;   filling the bag with the material;   sealing the bag; and   positioning a charged bag in the opening to be filled by conforming the bag to the volume of the opening.   

     The ease of use makes the product particularly well suited to a host of applications. The ability to open and reseal the bag would allow for flexible use where the specific size of the space to be filled is variable. As a useful feature, the otherwise closed container having the sealable opening could include a zipper type fastener or conventional bag sealer which would allow for adjustment of the amount of material in the bag. 
     As an option, the individual bags may also be reconfigurable into an assembly by using individual containers connected either end to end or atop one another. In order to maintain the connection, fasteners will be employed such as ties, zippers, heat, tape inter alia. 
     Having thus generally described the invention, reference will now be made to the accompanying drawings illustrating preferred embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of one embodiment of the present invention; 
         FIG. 2  is an enlarged view of the bag shown in  FIG. 1 ; 
         FIGS. 3A through 3C  are perspective views of possible shapes for the lightweight, non water retaining, non-biodegradable soil replacement material; 
         FIG. 4  is a perspective view of an assembly of the filled bags in accordance with one embodiment of the present invention; 
         FIG. 5  is a perspective view of the bags illustrating various opening means; and 
         FIG. 6  is a perspective view of the bag in situ. 
       Similar numerals denote similar elements. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference to  FIG. 1 , numeral  10  globally denotes the overall structure, the arrangement comprising a flexible bag, shown in the example to have an open top  12  and a closed bottom  14 . The container is made from a flexible material and is additionally mesh, an enlarged view of the mesh being illustrated in  FIG. 2  and denoted by numeral  16 . 
     In terms of suitable flexible materials for the container  10 , each will be selected from non biodegradable materials which may or may not include UV stabilization compounds in order to prevent UV degradation. This would be required where the bag is in direct exposure to the sun or some other source of ultra violet radiation. With respect to the material of which the bag is made, suitable polymer materials to fulfill this requirement include polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyester inter alia. In certain circumstance, it may be necessary to use high end or high performance materials such as polyvinyl fluoride film. 
     In order to facilitate water passage and moisture passage, the flexible bag is preferably composed of mesh or otherwise perforated to facilitate or mimic the concept of having a mesh structure. Depending on the intended use of the container, the mesh size may vary substantially from 0.1 mm to 10 mm. As will be appreciated by the user, the mesh pore size will vary depending on the surrounding earth formation and ground hydrology, etc. has high water content or is otherwise exposed to a great deal of drainage, or extremely fine or coarse existing soils. 
     Generally speaking, the size and charging of the flexible bag will vary from one intended use to another. One possibility is to have a unit approximately 8 feet in overall length and approximately 2 feet in diameter. 
     As illustrated in  FIG. 1 , the bag  10  has an open top; this is simply to illustrate the fact that the bag  10  is charged with granular fill material  18 , several examples of shapes of which are illustrated in  FIGS. 3A through 3C . In a similar manner to the bag  10 , the soil replacement material  18  will comprise a polymeric material and those materials that have been indicated suitable for use in the bag construction will also be readily applicable and useful in the formation of the soil replacement material  18 . Although it is not essential, one possible further feature is the provision of apertures  20  in the fill material  18  which may or may not penetrate from one side of the fill material to the other. In the instance where the openings  20  do not penetrate through the entire body, these will function effectively as blind holes and useful to retain moisture for passive evaporation. This will be discussed further in respect of the description for  FIG. 6 . 
     With reference to  FIG. 4 , shown is an assembly of individual containers  10  in the example, each unit  10  is interconnected with a similar unit by fasteners  22 . As suitable examples, the fasteners may comprise tape, ties, hook and loupe arrangements, string or other suitable means of fastening units together. 
     Turning to  FIG. 5 , shown is a further embodiment of the present invention where the container  10  is closed at both ends  12 . In this manner, the container  10  may be opened in a single section and reclosed once the container  10  is charged with filling material  18 . As one possible example, a plastic zipper  24  may be employed as shown in the example. As a further alternative, a conventional resealable opening, typically sold under the trademark Ziploc may be employed on the container for resealing purposes once the same has been charged with the material. 
     Although these examples have been shown with respect to  FIG. 5 , it will be evident that the container  10 , as referenced in  FIG. 1 , may be sealed by simply tying the open top once charged with a suitable tie (not shown), heat sealed, taped or otherwise fixedly secured to provide a seal. 
       FIG. 6  illustrates the containers  10 , both of which are closed and in situ against the walls  26  of a structure. As illustrated, the containers  10  are below the grade, referenced as numeral  28 , of the building. As is known in this field, soil could then be placed against each of the outer surfaces of containers  10  to provide adequate backfill against the walls  26 . 
     As referenced earlier in the specification, the arrangement as illustrated in  FIG. 6  has particular advantage in that the filled containers  10  effectively provide a layer of insulation against the exposed surface of the wall  26 . The exposed surface is only generally shown in  FIG. 6  and referenced by numeral  30 . It will be understood that the in  FIG. 6 , the illustration where the two containers  10  intersect a portion has been left open to simply demonstrate that the two do in fact meet at the corner. 
     In this application, the size of the openings in the mesh container  10  may be varied from one side of the container to the other to prevent the ingress of moisture through the exposed surface  30  of each of the walls  26 . In addition, the backfill within the containers  10  of  FIG. 6  (the backfill is not specifically shown) may be of the version that is apertured in order to trap moisture ingress through the mesh container. In this manner, the exposed surface  30  of each wall  26  is effectively thermally insulated as well as protected from moisture transmission. 
     The non-biodegradable materials may be comprised of recycled plastics as well as virgin plastic and additionally may incorporate other suitable materials made from paper as well as polymeric materials or other suitable recycled composite materials. In terms of the shapes that have been presented for the fill, a specific strength and density of the material selected will, of course, depend on the intended use of the product. 
     With respect to the flexible bag, the material that will be employed will be subject to substantial variation and will be variable in terms of the tensile strength. 
     Although embodiments of the invention have been described above, it is not limited thereto and it will be apparent to those skilled in the art that numerous modifications form part of the present invention insofar as they do not depart from the spirit, nature and scope of the claimed and described invention.