STABILIZING MAT AND METHOD OF STABILIZING AN
AREA OF TERRAIN USING THE STABILIZING MAT
Field of the Invention
[0001] The present invention relates to a stabilizing mat and a method of stabilizing an area of terrain using the stabilizing mat, and in particular, a stabilizing mat and method that employ tire treads arranged in a woven pattern.
Background of the Invention
[0002] Geotextiles have become commonplace in the construction of outdoor structures such as roads, embanlcments, railroad beds, and the like. Geotextile fabrics are commonly used to prevent erosion and control vegetation growth. Geotextile fabrics are typically made from engineered fiber materials and are available in both woven and non- woven form.
[0003] Geotextile stabilizing structures are commonly used to help maintain soil stability, particularly in and around roads and railways. The geotextile structures are typically buried below the surface of the terrain that is in need of stabilization. Geotextile structures are also typically made from engineered materials, such as polypropylene, and often take the form of grids and honeycomb arrays. [0004] While such geotextile stabilizing structures have been available for quite some time and have provided a significant improvement in the construction of structures such as roads, embankments, railways, and the like, they tend to be extremely expensive. This in turn has caused the overall cost of installing such structures to skyrocket in recent years.
[0005] It would be desirable to provide a geotextile stabilizing structure that can achieve the requisite terrain stabilization, but at a more reasonable cost. To date, however, no such stabilizing structure has been available.
Summary of the Invention
[0006] It is an object of the present invention to provide a terrain stabilization structure that performs stabilization in an effective manner, but at a more reasonable price.
[0007] In accordance with a first embodiment of the present invention, a stabilizing mat is provided that includes a plurality of warp members extending in a first direction spaced apart from one another a predetermined distance, and a plurality of weft members interleaved with the warp members and extending in a second direction substantially peφendicular to the first direction, wherein the waφ and weft members are formed from tire treads.
[0008] The stabilizing mat in accordance with the present invention overcomes the problems associated with traditional geotextile structures, in that it provides terrain stabilization comparable to commercially available geotextile stabilizing structures, but at a substantially reduced expense. Specifically, since recycled tires can be obtained at negative cost (recyclers often pay for disposal of tires), the stabilizing mat in accordance with the present invention can be offered to civil construction contractors at a very reasonable price compared to geotextile stabilizing structures made of engineered materials such as polypropylene.
[0009] In accordance with another embodiment of the present invention, a method of stabilizing an area of terrain includes the steps of (1) providing a stabilizing mat comprising a plurality of waφ members extending in a first direction spaced apart
from one another a predetermined distance, and a plurality of weft members extending in a second direction substantially peφendicular to the first direction, wherein the weft members and waφ members are interleaved and are formed from tire treads, and (2) burying the stabilizing mat a predetermined distance beneath the area of terrain to be stabilized.
[0010] In accordance with an alternative method of the present invention, the waφ and weft members are provided at the site of the area of terrain to be stabilized, and woven together on site. This latter technique alleviates some of the problems associated with transporting preassembled stabilizing mats. A ten-foot square preassembled stabilizing mat weighs approximately one ton. This weight can present a problem with installing the preassembled mats. In such a case, it may be preferable to weave the waφ and weft members together on site.
[0011] The stabilization structure and method in accordance with the present invention is particularly useful for stabilizing the area under roads and railroad beds. In the case of railroad beds, the stabilization structure prevents the ballast from moving under the influence of passing rail cars and thus preserves the integrity of the bed over extended periods of time.
[0012] The stabilization structure and method in accordance with the present invention is also useful for slope protection in and around roads and highways. Where rocks are used to prevent erosion, the stabilization structure can be placed beneath the rocks to prevent the ground from sagging.
Brief Description of the Drawings
[0013] For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description of a preferred mode of
practicing the invention, read in connection with the accompanying drawings, in which:
Fig. 1 is a top view of a stabilizing mat in accordance with one embodiment of the present invention;
Figs. 2a-2c are cross-sectional views showing the position of the stabilizing mat beneath an area of terrain to be stabilized; and
Fig. 3 is a perspective view showing two installation methods in accordance with the present invention.
Detailed Description of the Preferred Embodiment
[0014] Fig. 1 shows a stabilizing mat 1 in accordance with a first embodiment of the present invention. The stabilizing mat 1 includes a plurality of waφ members 2j- 2n extending in a first direction spaced apart from one another a predetermined distance. The mat also includes a plurality of weft members 3ι-3„ extending in a second direction substantially peφendicular to the first direction. As shown in Fig. 1, the weft members 3 are interleaved with the waφ members 2 to provide a woven mat. The waφ and weft members are formed from tire treads, thus providing a substantial cost savings. The tire treads are formed by cutting a recycled tire at the juncture between the tire tread and the sidewalls. The tire tread has substantial strength since it includes the steel reinforcing belt from the original tire.
[0015] Fig. 1 shows that the waφ and weft members overlie each other at several positions. In the case of preassembled stabilizing mats, it is desirable to secure the waφ and weft members to one another at least at some of the overlying positions. This will ensure that the stabilizing mat stays together during transport, handling and installation.
[0016] While any securing method could be used, it is preferred to use mechanical fasteners 4 (e.g., rivets, screws, nut/bolt assemblies, etc.) at a variety of positions where the waφ and weft members overlie each other. While it is possible to provide a fastener 4 at every such location, it is not deemed necessary in most applications. Other fastening techniques, such as adhesives, could also be used alone or in combination with the mechanical fasteners.
[0017] Fig. 1 also shows that the stabilizing mat includes a first weft member 3ι and a last weft member 3n and the end portions of the waφ members 2 extend beyond at least one of the first and last weft members. This will allow for several stabilizing mats to be joined end to end in the event the area of terrain to be stabilized is greater than the area of an individual stabilizing mat.
[0018] It is also possible for the end portions of the weft members 3 to extend beyond the first waφ member 2 and the last waφ member 2n. This will allow several stabilizing mats to be joined side to side.
[0019] Figs. 2a-2c show an example of how the stabilizing mat 1 is used to stabilize an area of terrain. Fig. 2a shows the terrain as excavated to a predetermined depth. The stabilizing mat 1 shown in Fig. 1 is then positioned at the bottom of the excavated site (Fig. 2b). The excavated site is then filled with appropriate fill material Fl, F2 to cover the stabilizing mat 1. The presence of the stabilizing mat 1 will prevent any substantial movement of the terrain beneath the mat, and thus provide a significant improvement in the stabilization of the surface of the terrain. [0020] Although not shown in the drawings, it is also possible to provide other layers of geotextile fabric either above or below stabilizing mat 1 to perform other functions, such as water/silt separation, and the like. Such a geotextile fabric will
prevent silt migration to the surface of the terrain, which is a significant problem in some applications, such as railroad beds.
[0021] Fig. 3 shows that the stabilizing mat 1 can be preassembled off site and then simply installed as a unit on site. Due to the substantial weight associated with tire treads, however, in some instances the preassembled mats may be too heavy to permit handling and installation on site. In such a case, Fig. 3 also shows that the waφ members can be provided in a roll 10, and the weft members can be provided in a stack 11 pre-cut to a specific length. For example, in the construction of a new railroad bed, the weft members 3 could be provided at a length that corresponds to the width of the excavation site beneath the railroad bed. The waφ members 2 could then be cut from the roll 10 to whatever length that is convenient to handle on site. The waφ and weft members could then be woven together within the excavation area. If the waφ and weft members are woven on site, fastening members may not be necessary, as the waφ and weft members should not experience much movement once buried below the terrain to be stabilized.
[0022] While the present invention has been particularly shown and described with reference to the preferred mode as illustrated in the drawings, it will be understood by one skilled in the art that various changes in detail may be effected therein without departing from the spirit and scope of the invention as defined by the claims. For example, while the stabilizing mat has been described with reference to subterranean use, it could also be used to provide a temporary lateral foundation for cranes and other heavy machinery.