Improved connection device for fixing expanded cell confinement structures and procedures for manufacturing the same

Abstract

A connecting device for securing two expanded cellular confinement structures includes: an insertion element; an integral stem extending perpendicularly from the insertion element; and an integral handle extending perpendicularly from the stem at one end of the stem away from the insertion element. One or more prongs may protrude from the insertion element. The device may have a washer between the handle and the insertion element. The handle may be curved or polygonal.

Description

Improved connection device for fixing expanded cell confinement structures and procedures for manufacturing the same Technical field This description relates to connecting devices for expanded cell confinement structures for the confinement of fill material. In particular, this description relates to improved connectors with burrs and procedures used to fasten at least two expanded cell confinement structures together. Background A cell confinement structure serves to increase the load-bearing capacity, stability, and erosion resistance of the backfill materials placed within the system's cells. One commercially available system is the Geoweb® plastic band confinement structure sold by Reynolds Presto Products, Inc., Appleton, Wisconsin. Geoweb® cells are made of high-density polyethylene strips joined by welds on their faces in a side-to-side relationship at alternating spacing, so that when the strips are stretched in a direction perpendicular to the strip faces, the resulting band section has a honeycomb appearance, with sinusoidal or wavy cells. Geoweb® sections are lightweight and are shipped in their folded form for ease of handling and installation. Geoweb® systems have been described in U.S. patents. 6, 395, 372; 4, 778, 309; 4, 965, 097; y 5, 449, 543. Cell confinement structures are typically arranged adjacent to one another and then connected. In the past, these sections have been connected using staples, wires, cable ties, etc. These methods are labor-intensive and time-consuming to construct. In many implementations, these types of connections are difficult to use due to the specific terrain or site conditions. Most of the time, these types of connection systems require generator power and air-driven compressors. The power requirement can further complicate matters, given the environment or terrain where such cell confinement systems are typically located.The unit cost per connection can be quite high in smaller projects, as the fixed costs associated with supplying generators and air compressors are similar in both small and large installations. Furthermore, some of these connection devices provide relatively weak structural connections and are not durable. In some implementations, this is not a problem. However, in many applications, speed is critical, and the availability of power equipment is a challenge. Reynolds Presto Products developed a connection device for cell confinement structures, described in document US 8, 092122. While this connection device solves many of the problems described above, improvements are desirable. Summary of the description In one aspect, a connecting device is provided for fastening two expanded cell confinement structures. The connecting device includes: an insertion member having first and second opposing insertion ends and an insertion member extension between them; an integral stem generally extending perpendicularly from the insertion member extension and separated from each of the first and second insertion ends; an integral handle member generally extending perpendicularly from the stem at one end of the stem away from the insertion member; the handle member having first and second handle ends and a handle member extension between them; the stem being separated from each of the first and second handle ends; and a plurality of burrs projecting from the insertion member. The plurality of burrs protrudes from the insertion member towards the handle member. The insertion member extension includes an outer face facing away from a remaining portion of the connecting device; an inner face facing the handle member; and the plurality of burrs protruding from the inner face of the insertion member extension toward the handle member. The stem intersects the inner face; and the plurality of burrs includes at least two burrs projecting from the inner face on each of the opposite sides of the insertion member extension. In many examples, the first and second insertion ends join the outer face and the inner face. In exemplary embodiments, the first insertion end has a first flat end face; and the second insertion end has a second flat end face. Some implementations include the outer face having a first angled section; a second angled section; and a straight middle section extending between the first angled section and the second angled section; the first angled section extending from the first insertion end to the middle section at a non-zero angle; and the second angled section extending from the second insertion end to the middle section at a non-zero angle. In exemplary embodiments, the inner face has a first portion and a second portion; the first portion being between the first insertion end and the stem; the second portion being between the second insertion end and the stem; the plurality of burrs includes at least two burrs extending from the first portion towards the handle member; and the plurality of burrs includes at least two burrs extending from the second portion towards the handle member. Exemplary embodiments may include a first burr on the first portion adjacent to the first insertion end; and a first burr on the second portion adjacent to the second insertion end. In some examples, the first portion is a straight extension between the shank and the first insertion end; and the second portion is a straight extension between the shank and the second insertion end. One or more embodiments may have the first portion including a first straight section extending from the stem; and a first beveled section angled away from the first straight section downwards to the first insertion end at a non-zero angle; and the second portion including a second straight section extending from the stem; and a second beveled section angled away from the second straight section downwards to the second insertion end at a non-zero angle. In some implementations, a first burr on the first portion is adjacent to the first insertion end; a second burr on the first portion is between the first straight section and the first chamfered section; a first burr on the second portion is adjacent to the second insertion end; and a second burr on the second portion is between the second straight section and the second chamfered section. Many examples include a stem having a stem length between the insertion member and the handle member; the stem length being greater than the length of both the first straight section and the second straight section. In some examples, the length of the stem is less than half the length of the handle member and the insertion member. Many examples included a larger distance between the inner and outer face of the insertion member extension of at least 5 times the height of the burrs. In one or more embodiments, the handle member, the insertion member, and the stem are a single, solid piece. In one or more embodiments, the handle member extension includes first and second rounded lugs projecting therefrom. In one or more embodiments, the first and second lugs project from the insertion member at the first and second handle ends, and the handle member extension is straight between the first and second lugs. In exemplary embodiments, the connecting device has a longitudinal axis bisecting the device that extends through each of the insertion member, the handle member, and the stem; and each burr in the plurality of burrs has at least one chamfered surface terminating in a point. In one or more embodiments, each beveled surface of the burrs extends along a plane that intersects the longitudinal axis. Many implementations include each beveled surface of the burrs that extends along a plane intersecting the longitudinal axis on: the stem, the handle member, or in the space above the handle member and away from the insertion member, when the connecting device is oriented with the handle member vertical and the insertion member lower. In exemplary embodiments, the connecting device is symmetrical around the longitudinal axis. In another aspect, a kit is provided. The kit includes: a plurality of unit cell bands made of elongated plastic strips joined together in separate areas; the strips forming cell walls; defining at least some of the cells with open slots that can be aligned with open slots in adjacent unit cell bands in cell overlap regions, the cell overlap regions having opposite first and second sides; and a plurality of connecting devices usable for fastening adjacent unit cell bands together across the slots in the cell overlap regions; each connecting device including: an insertion member having opposite first and second insertion ends and an insertion member extension between them;the insertion member being positioned on the second side of the cell overlap region; a plurality of burrs projecting from the insertion member and being positioned towards the first side of the cell overlap region; an integral stem generally extending perpendicular to the insertion member extension and separated from each of the first and second insertion ends; the stem being positioned through the cell overlap region by extending through aligned grooves; and an integral handle member generally extending perpendicularly from the stem at a stem end away from the insertion member; the handle member having first and second handle ends and a handle member extension between them; the stem being separated from each of the first and second handle ends;and the handle member being able to be placed on the first side of the cell overlap region.; Brief description of the drawings FIG. 1 is an exploded perspective schematic view of a cell confinement system and connecting devices, prior to end assembly, using principles according to this description; FIG. 1A is an exploded perspective schematic view of a cell confinement system and connecting devices, prior to side assembly, using principles according to this description; FIG.2 is a perspective view of two cells that are part of an expanded cell confinement structure before they are connected to each other; FIG.3 is a perspective view of two expanded cell confinement structures connected together using connecting devices constructed according to the principles of this description; FIG. 4 is a perspective view of an embodiment of a connecting device, constructed according to the principles of this description; FIG. 5 is another perspective view of the connecting device of FIG. 4; FIG.6 is a top plan view of the connecting device of FIGS.4 and 5; FIG.7 is an end view of the connecting device of FIG.6; FIG. 8 is another end view of the connecting device of FIG. 6, representing the opposite end to that shown in FIG. 7; FIG.9 is a perspective view of a second embodiment of the connecting device constructed according to the principles of this description; FIG.10 is another perspective view of the connecting device of FIG.9; FIG.11 is a top plan view of the connecting device of FIG.9; FIG.12 is an end view of the connecting device of FIG.9; FIG.13 is another end view of the connecting device of FIG.9, representing the opposite end to that shown in FIG.12; FIG.14 is a schematic perspective view of a stage of use of the connecting device together with a prestressing rod; FIG.15 is a schematic perspective view of another stage of use of the connection device with a prestressing rod; FIG.16 is a schematic perspective view of another stage of use of the connection device with a prestressing rod; FIG.17 is an enlarged view of an outline of portion A of the connecting device of FIG.6; FIG.18 is an enlarged view of an outline of portion B of the connecting device of FIG.6; FIG. 19 is an enlarged view of a portion of the connecting device in FIG. 4; and FIG. 20 is a schematic perspective view depicting the connecting device of FIG. 4 that connects two expanded cell confinement structures that are being tested to determine their performance on a tensile testing machine. FIG.21 is a perspective view of an alternative connecting device, which is not part of the claimed subject matter; FIG.22 is a bottom perspective view of the connecting device of FIG.21; FIG.23 is a front view of the connecting device of FIG.21; FIG.24 is a top plan view of the connecting device of FIG.21; FIG. 25 is a front view of the connecting device of FIG. 21, but showing a variation in the insertion member; FIG.26 is a perspective view similar to FIG.3, but showing the connecting device of the FIGS. 21-25; FIG. 27 is a perspective view of another embodiment of a connecting device, constructed according to the principles of this description; FIG.28 is a bottom perspective view of the connecting device of FIG.27; FIG.29 is a front view of the connecting device of FIG.27; FIG.30 is a top plan view of the connecting device of FIG.27; FIG. 31 is a front view of the connecting device of FIG. 27 but showing a variation in the insertion member, which is not part of the claimed subject matter. Detailed description Figures 1 and 1A depict a cell confinement system 14. In the particular implementation shown, the cell confinement system 14 includes first and second unit cell bands 18. The first cell band is shown in Figure 20, while the second cell band is shown in Figure 22. In the embodiment shown, the cell confinement system 14 further includes at least one connecting device 24 for fastening the first band 20 and the second band 22 together. Figure 1 shows system 14 before the first and second bands 20 and 22 are connected end-to-end. Figure 1A shows system 14 before the first and second bands 20 and 22 are connected side-by-side (laterally). Each of the expanded cell confinement structures 18 has a plurality of plastic strips 26 that are joined together, one strip to the next, at alternating and equally spaced joining areas 28 to form cell walls 30 of individual cells 32. When the plurality of strips 26 are stretched in a direction perpendicular to the strip face, the strips 26 bend sinusoidally and form cell bands 20 and 22 in a repeating cell pattern. Each cell 32 has a cell wall 30 that is made up of a strip 26 and a cell wall 30 made of a different strip 26. In this embodiment, the strips 26 define openings 34. The openings 34 can be used to receive prestressing rods to reinforce the bands 20 and 22 and improve the stability of the band installations by acting as continuous integral anchor members to prevent unwanted displacement of the bands 20 and 22. The openings 34 also help to allow the interlocking of aggregates while maintaining sufficient wall stiffness for the construction site backfill. Optimized opening sizes and patterns are described in U.S. Patents 6,395, and 372, incorporated by reference in this invention. Figure 2 shows two cells 32. The cells 32 in Figure 2 differ slightly from the representation in Figure 1, as the strips 26 do not contain all the openings 34 as depicted in Figure 1. The openings 34 can be used optionally, depending on the implementation. Figure 2 depicts open slots 36 defined by the cell walls 30 in the strips 26. The slots 36 are used to cooperate with the connecting device 24 in order to fasten adjacent strips 20, 22 together. Figure 3 shows the cell confinement system 14 with the first band 20 and the second band 22 fixed together by the connecting device 24. In the embodiment of Figure 3, at least one connecting device 24 is used, and as shown, a plurality of connecting devices 24 are used. Figure 3 specifically shows two connecting devices 24. The openings 34 are omitted from Figure 3 for clarity. Still with reference to FIG. 3, a cell overlap region 38 is shown. In particular, two cell overlap regions 38 are shown. The cell overlap region, as shown, includes an open slot 36 of the first unit cell strip 20 aligned with the open slot 36 of the second unit cell strip 22. The cell overlap region 38 defines a first face 40 and an opposing second face 42. It can be observed that the connecting device 24 penetrates or passes through the overlap region 38, with part of the connecting device 24 on the first side of the overlap region 38, while another part of the connecting device 24 can be observed as ghost lines on the second side 42 of the overlap region 38. An example of this will be described later. Reference is made to FIGS. 4-8. FIGS. 4-8 represent an exemplary embodiment of the connecting device 24. In the embodiment shown, the connecting device 24 includes an insertion member 44. The insertion member 44 has opposing first and second insertion ends 46 and 47, and an insertion member extension 48 between the first insertion member end 46 and the second insertion member end 47. A first length is defined by the distance between the first insertion member end 46 and the second insertion member end 47. The insertion member extension 48 includes an outer face 54 oriented opposite a remaining portion of the connecting device 24. While many embodiments are possible, where shown, the outer face 54 has a straight, generally flat, middle section 55, usually centered on a stem 64. The outer face 54 further includes a first angled section 56 and a second angled section 57. The middle section 55 extends between the first angled section 56 and the second angled section 57. The first angled section 56 extends from the first insertion end 46 to the middle section 55 at a non-zero angle (FIG. 6) , which may be 60° or less; 45° or less; 30° or less; for example, 15-25°, or approximately 20°. The second angled section 57 extends from the second insertion end 47 to the mid-section 55 at a non-zero angle β (FIG. 6), which may be 60° or less; 45° or less; 30° or less; for example, 15-25°, or approximately 20°. In preferred arrangements, the angle of the first angled section 56 and the second angled section 57 are the same. The insertion member extension 48 includes an inner face 66 oriented towards a handle member 70. The insertion member extension 48 is on an opposite side as the outer face 54. As can be seen in Figures 5 and 6, the stem 64 intersects with the inner face 66. The first and second insertion ends 46 and 47 join the outer face 54 and the inner face 66 in this embodiment. Although many different forms are possible, in the embodiment shown, the first insertion end 46 has a first flat end face 67, and the second insertion end 47 has a second flat end face 68. Still with reference to FIGS. 4-8, an exemplary connecting device 24 includes, as mentioned above, an integral stem 64 extending from the extension member 48 of the insertion member and separated from each of the ends 46, 47 of the first and second insertion members. A variety of implementations are possible. In the embodiment shown, the stem 64 generally extends perpendicularly from the extension 48 of the insertion member. The stem 64 has a length defined as between the insertion member 44 and a handle member 70, which is described below. The length of the stem 64 is less than the length of the insertion member 44, as shown in one example. In the embodiment shown, the connecting device 24 includes, as mentioned above, the handle member 70. Preferably, the handle member 70 is integral with the stem 64. The handle member 70 extends from the stem 64 at one end of the stem 64 away from the insertion member 44. In the example shown, handle member 70 has first and second handle ends 72 and 73. Between the first handle end 72 and the second handle end 73 is a handle member extension 74. In the embodiment shown, the stem 64 is separated from each of the first and second handle ends 72, 73. The handle member 70 has a defined length between the first handle end 72 and the second handle end 73. While many designs are contemplated, in the particular embodiment illustrated, the length of the handle member 70 is greater than the length of the insertion member 44. In one example, the length of the stem 64 is less than half the length of the handle member 70 and the insertion member 44. These relative dimensions cooperate with the groove 36 and allow for quick and convenient attachment of the first and second bands 20, 22. In exemplary embodiments, the length of member 70 of handle is not greater than 100 mm, typically 30-80 mm, for example, 45-55 mm. In the embodiment shown, the length of the handle member 70 is at least 10 percent greater than the length of the insert member 44. This relative geometry helps ensure that the connecting device 24 remains in place within the groove 36 and does not come loose. In the embodiment shown, the handle member extension 74 includes first and second lobes or lugs 76 and 77 projecting therefrom. The lobes or lugs 76 and 77 project from the insertion member 44. In the embodiment shown, the first and second lugs 76 and 77 are rounded and are uniform with the first and second handle ends 72 and 73. The handle member extension 74 is shown as straight between the first and second lugs 76 and 77. According to the principles of this description, the connecting device 24 includes a plurality of burrs 200. The burrs 200 protrude from the insertion member 44 and into the handle member 70. Although many different arrangements are possible, in the example shown, the plurality of burrs 200 protrude from the inner face 66 of the insertion member extension 48 and towards the handle member 70. Reference is made to FIGS. 17 and 18, which show an enlarged portion of the insertion member 44 in sections A and B of FIG. 6. The plurality of burrs 200 includes at least one burr 204, 205 projecting from the inner face 66 on opposite sides of the insertion member extension 48. By the expression "opposite sides of the insertion member extension", it means opposite sides of the extension 48 from where the stem 64 intersects the intersection 48. In many preferred embodiments of the invention, the plurality of burrs 200 includes at least two burrs 204, 206 (FIG. 17) on one side of the stem 64, and two burrs 205, 207 (FIG. 18) on the opposite side of the stem 64 protruding from the inner face 66 of the insertion member extension 48. The inner face 66 has a first portion 211 and a second portion 212. The first portion 211 is between the first insertion end 46 and the stem 64. The second portion 212 is between the second insertion end 47 and the stem 64. The plurality of burrs 200 includes at least one burr 204 and, in this example, two burrs 204, 206, extending from the first portion 211 into the handle member 70. The plurality of burrs 200 includes at least one burr 205 and, in this example, two burrs 205, 207, extending from the second portion 212 into the handle member 70. As can be seen in FIGS. 17 and 18, the first burr 204 in the first portion 211 is adjacent to the first insertion end 46. Similarly, the first burr 205 in the second portion 212 is adjacent to the second insertion end 47. The first portion 211 includes a straight section 214 extending from the stem 64. Similarly, the second portion includes a straight section 215 extending from the stem 64. In the embodiment of FIGS. 4-8, 17, and 18, the first portion 211 includes a first beveled section 218 angled away from the first straight section 214 and downward to the first insertion end 46 at a non-zero angle 260 (FIG. 17). The angle 260 may be, for example, less than 60°; less than 45°; less than 30°; approximately 10-25°; and preferably, approximately 20°. In FIG. 18, the second portion 212 includes a second beveled section 219 that is angled away from the second straight section 215 and downward to the second insertion end 47 at a non-zero angle 262. The non-zero angle 262 may be less than 60°; less than 45°; less than 30°; between 10 and 25°; and preferably approximately 20°. The angle 262 will be approximately the same as the angle 260 of the first beveled section 218. As will be described later in connection with the embodiment of FIGS. 11-13, in other embodiments, the first portion 211 and the second portion 212 may be straight between the stem 64 and the first insertion end 46. Similarly, the second portion 212 may be straight between the stem 64 and the second insertion end 47. That is, in the embodiment of FIGS. 11-13, there are no chamfered sections 218, 219. Stem 64 has a stem length between insertion member 44 and handle member 70. In this example, the stem length is greater than the length of the first straight section 214 and the second straight section 215. The first burr 204 in the first portion 211 is adjacent to the first insertion end 46, while the second burr 206 is between the first straight section 214 and the first beveled section 218. The first of the burrs 205 in the second portion 212 is adjacent to the second insertion end 47, while the second burr 207 in the second portion 212 is between the second straight section 215 and the second beveled section 219. The 200 burrs can have a variety of shapes and sizes. Typically, the larger distance between the inner face 66 and the outer face 54 shown in dimension 222 in FIG. 17 is at least five times the height h1 of burr 204 and the height h2 of burr 206. Burrs 205 and 207 also have heights h1 and h2. In the example shown, the height h1 of burr 204 and burr 205 is the same, while the height h2 of burrs 206 and burr 207 is the same. In many exemplary embodiments, the heights h1 and h2 are equal, although many different geometries could be used. In this example, the height of each of h1 and h2 is less than 0.254 cm (0.1 inches), greater than 0.0508 cm (0.02 inches) and typically 0.127-0.2286 cm (0.05-0.09 inches), preferably about 0.1905 cm (0.075 inches).In some examples, the heights h1, h2 will be approximately 3-10%, typically approximately 4-6%, or approximately 5%, of the overall length of the insertion member 44. In the exemplary embodiment shown, burrs 204 and 205 are similar in shape, while burrs 206 and 207 are similar in shape. Exemplary usable dimensions for these burrs 200 are shown below. Regarding burrs 204 and 205, which are located adjacent to end faces 46 and 47, burrs 204 and 205 have at least one chamfered surface 230 (burr 204) and 231 (burr 205). The chamfered surface 230 and 231 intersects a vertical surface 232 and 233. In the example shown, the vertical surfaces 232 and 233 are generally orthogonal to the respective chamfered section 218 and 219. The beveled surface 230, 231 intersects with the vertical surface 232, 233 at a terminal point 234, 235. Each of the chamfered surfaces 230, 231 forms a ramp and is angled with respect to the end faces 46, 47. Each chamfered surface 230, 231, in this embodiment, extends along a plane (the edge of the plane being shown in dashed lines in 264, 266 in FIGS. 17 and 18) that intersects a longitudinal axis 240 (FIG. 6) The longitudinal axis 240 bisects the device 24 and extends through each of the insertion member 44, the handle member 70 and along the stem 64. In the exemplary embodiment shown, each chamfered surface 230, 231 extends along a plane that intersects the longitudinal axis 240 in the vicinity of the stem 64, the handle member 70 or in the space adjacent to (above) the handle member 70 and away from the insertion member 44, when the connecting device 24 is oriented with the handle member 70 in the most vertical position and the insertion member in the lowest position. The beveled surface 230, 231 is at an angle to a plane containing the end surface 46, 47 at angle 242, 243. The angle 242, 243 can be a variety of angles and, in the embodiment shown, varies between 20-80°, for example 25-45°, and is shown at 30°. The burrs 206, 207 similarly have a chamfered surface 244, 245 that intersects the vertical surface 246, 247 at the terminal tip 248, 249. The chamfered surface 244, 245 extends along a plane (the edge of the plane is shown as dashed lines in 268, 270 in FIGS. 17 and 18) that intersects the longitudinal axis 240. In the preferred embodiment of the invention shown, the chamfered surface 244, 245 intersects the longitudinal axis 240 in the vicinity of the shank 64, the handle 70, or in a space (above) the handle 70 and away from the insertion member 44, when the connecting device 24 is oriented with the handle member 70 vertical and the insertion member 44 lower. The beveled surface 244, 245 can be at a variety of different angles, the angle shown in 250, 251 being with respect to the bevel section 218, 219.The angle 250, 251 is not a right angle and is greater than 180°; less than 270°; in a range of 120-150°, preferably approximately 135°. Next, with reference to FIG. 19, each of the burrs 204, 205, 206, 207 has an inside radius, with respect to the insertion member 44, shown in 270, 271, 272, 273, respectively. While a variety of sizes are possible, and they can vary between each one, in this example, the inside radius 270, 271, 272, 273 is approximately the same, within a range of 0.0254 cm–0.0762 cm (0.010 in–0.030 in), typically approximately 0.0381–0.0635 cm (0.015–0.025 in) or approximately 0.0508 cm (0.020 in). In relation to the length of the insertion member 44, the measurement of the inner radius 270, 271, 272, 273 is greater than 0.75%; less than 5%; and typically about 1-1.5% or about 1.3% of the length of the insertion member 44. With reference again to FIG. 6, the connecting device 24 can be manufactured using a variety of techniques. Preferably, the connecting device 24 is made from a single solid piece, such as injection-molded plastic, including high-density polyethylene or polypropylene. In other embodiments, the connecting device 24 could be made from a metallic material, either molded as a single piece or by joining multiple parts. Still with reference to FIG. 6, in this embodiment, the connecting device 24 is symmetrical with respect to the longitudinal axis 240. Other arrangements are possible. Returning now to the embodiment of FIGS. 9-13, an alternative connecting device is shown in 24. The connecting device 24 is the same as the device 24 described above (and therefore uses the same part numbers), with the exception of the first portion 211 and the second portion 212 (FIG. 11). The first portion 211 is straight between the stem 64 and the first insertion end 46. Similarly, the second portion 212 is straight between the stem 64 and the second insertion end 47. That is, in the embodiment of FIGS. 11-13, there are no chamfered sections 218, 219. Returning to FIG. 3, it can be observed that, during use, the connecting device 24 will have the handle member 70 on one side 40 of the overlap region and the insertion member 44 on the other side 42 of the overlap region 38. The stem 64 extends through the overlap region 38. The procedures for using the connecting device 24 are described later. In use, the connecting device 24 (which includes 24) can be used to fix two expanded cell confinement structures together. The procedure includes aligning two expanded cell confinement structures 18 such that at least one open slot 36 defined by the first band 20 is aligned with at least one slot 36 defined by the second band 22 to form the overlap region 38. The connecting device 24 (or 24') is provided. The connecting device 24 (or 24') is used by inserting the insertion member 44 from the first side 40 of the overlap region 38 through the aligned opening grooves 36 of the overlap region 38. This provides the insertion member 44 on the second side 42 of the overlap region 38 with the plurality of burrs 200 protruding from the insertion member 44 into the second side 42 of the overlap region 38. It provides the handle member 70 on the first side 40 of the overlap region 38. It provides the stem 64 extending through the overlap region 38. The procedure also includes rotating handle member 70 to rotate the connecting device 24 within the overlap region 38. This helps to lock the connecting device 24 within the grooves 36. An example of the use of a prestressing rod 110 in relation to the connector device 24 of FIGS is shown. 4-8 as shown in FIGS. 14-16. In FIG. 14, the prestressing rod 110 is illustrated as wrapped around the handle member 70 in the wrap 112. The prestressing rod 110 is positioned beneath the handle member 70 and is wrapped over one side of the handle 70. The prestressing rod 110 continues to wrap around the upper portion of the handle 70 to form a cross wrap. In FIG. 14, it can be observed how the insertion member 44 is inserted or engaged in the grooves 36 of two adjacent bands 20, 22, either end-to-end or edge-to-edge. The prestressing rod 110 can also be observed extending through the grooves 36 of the bands 20, 22, although the grooves 36 are not visible in FIG. 14. FIG. 15 shows the complete coupling of the connector device 24 through the slots 36. It can be observed that the burrs 200 press against the band 22. In FIG.Figure 16 illustrates the final stage of rotating the connector device 24 to lock the connector device 24 into the slots 36. Comparing FIGS. 15 and 16, it can be observed that the connector device 24 rotates approximately 90 degrees. The 24, 24 connection device can be used in a kit that includes a plurality of expanded cell confinement structures 18 and a plurality of the 24, 24 connection devices usable for connecting the cell confinement structures. During use, the grooves 36 will be non-circular, for example, elliptical, elongated circular, or circuit-shaped. In one embodiment, the grooves 36 are shaped like two semicircles separated by a rectangle, one side of which is equal to the diameter of the semicircle. When in use, this shape will have a major axis and a minor axis. The aspect ratio of the usable grooves 36, as a ratio of the minor axis to the major axis, is approximately 3:11. When compared to the dimensions of the connecting device 24, the major axis of the groove 36 has a length that is 85–95%, for example, 92%, of the length of the insert member 44. The minor axis of the groove 36 will be 20–30%, for example, approximately 25%, of the length of the insert member 44. In addition, the minor axis of slot 36 will be approximately 101% of the width or thickness of the connecting device 24. Experimental The connector device 24 (FIGS. 4-8) was analyzed, along with the connector device 24 (FIGS. 9-13) and the prior art connector device described in US patent 8,092,122 (burr-free). The devices were placed in the slots 36 of the cell confinement structures 18 and subjected to a tensile load, i.e., a pulling force. The test procedure used a modified version of ASTM D4885 to evaluate the performance of the connecting devices by subjecting test specimens to tensile loading using a Curtis "secure grip" tensile testing machine. The specimens were prepared by inserting a connector through the slots of two pieces of cell-confining material, and then folding the cell-confining material pieces and inserting them into opposing clamps of the tensile testing machine. A new connector and new pieces of cell-confining material were used for each test run. Figure 20 illustrates an assembled test specimen, such as the connecting device 24 in Figure 4, in the tensile testing machine 300.The specimens were clamped across their entire width in the clamps of a constant-rate extension tensile testing machine operating at a prescribed extension rate, applying a uniaxial load to the specimen until failure. The machine was equipped with a device to record the tensile force and the amount of grip separation with an accuracy of ±2%. In addition to the tensile force and separation, the type of failure was also recorded, noting whether the connector broke, slipped through the groove, or tore through the confining material. The following results were obtained: results: As demonstrated by the results, the connecting device 24 (FIGS.4-8) performed best, failing at a resistance of 144.51 kg (318.6 lbs), which was better than the connecting device of the prior art. Device 24 outperformed device 24. Both device 24 and 24 outperformed the connecting device of the prior art. Connecting device 24 (FIGS.9-13) failed at a resistance of 136.80 kg (301.6 lbs). As demonstrated above, the embodiments of the present invention address a common failure mode of connecting devices, namely, slippage through a groove. In many prior art devices, a connector may slip due to, for example, an inferior design. Additionally, many prior art devices remain intact but slip out of coupling with the geocell. The embodiments of the present invention address the loss of coupling with a geocell by increasing the pull-out strength of the connector. In some embodiments, the present invention is a connector that has a pull-out strength of more than 134.26 kg (296 lbs) when measured using a modified version of ASTM D4885 as described above in relation to the test system shown in Figure 20. Additional realizations and alternative designs, FIGS.21-31 Figures 21-31 show additional embodiments for the connecting device 24. The alternative design of Figures 21-26, which is not part of the claimed subject matter, is shown in Figure 424, while the embodiment of Figures 27-30, as well as the alternative design of Figure 31, which is not part of the claimed subject matter, are shown in Figure 624. The connecting device 424, 624 has many elements in common with the connecting device 24, and these will use common part numbers, but the description of each element will not be repeated here. Rather, the description of those common elements is incorporated here by reference. The connecting device 424, 624 has an insertion member 44. In the embodiment of Figure 25 and Figures 27-30, the insertion member 44 includes burrs 200, as shown and described with respect to Figures 27-30. 4-19, above. In the alternative design of FIGS. 21-26 and FIG.31, which is not part of the claimed subject matter, the insertion member 44 does not include burrs along the inner face 66. Rather, the inner face 66 is burr-free and is shown in 466. In this embodiment, the inner face 466 has a first angled section 474 and a second angled section 476. A first mid-section 478 extends between the first angled section 474 and the stem 64. A second mid-section 480 extends between the second angled section 476 and the stem 64. The mid-sections 478 and 480 are shown as generally flat and parallel to the mid-section 55 on the outer face 54. The first angled section 474 extends from the first insertion end 467 to the first mid-section 478 at a non-zero angle, which may be 60° or less; 45° or less; 30° or less; for example, 15–25°, or approximately 20°. The second angled section 476 extends from the second insertion end 468 to the second mid-section 480 at a non-zero angle, which may be 60° or less; 45° or less; 30° or less; for example, 15-25°, or approximately 20°.In preferred arrangements, the angle of the first angled section 474 and of the second angled section 476 are the same. The inner face 466 is oriented towards the handle member 70. The stem 64 intersects with the inner face 466. The first and second insertion ends 467 and 468 form a bridge between them in order to join the outer face 54 and the inner face 466, in this embodiment. The connecting device 424, 624 has a stem 64 and a handle member 70. The handle member 70 has variations of device 24, and will be described further below. Figure 23 shows the connecting device 424 with a central longitudinal shaft 482, which generally bisects the connecting device 424 through the insertion member 44, the stem 64, and the handle member 70. Similarly, Figure 29 shows the connecting device 624 with a central longitudinal shaft 682, which generally bisects the connecting device 624 through the insertion member 44, the stem 64, and the handle member 70. The connecting device 424, 624 is symmetrical about the longitudinal shaft 482, 682. The connecting device 424, 624 further includes a washer section 490. The washer section 490 is located between the handle member 70 and the insert member 44. The washer section 490 helps to contain the initial material in the cell confinement system 14 and prevents the material from migrating first through the open slots 36. Additionally, the washer section 490 is aesthetically pleasing. The washer section 490 can be made with many different appearances than those shown, but the one shown is considered attractive. In the exemplary embodiment shown, the washer section 490 is illustrated as cylindrical with a diameter perpendicular to the longitudinal axis 482, 682. Washer section 490 has a first surface 492 and a second surface 494 opposite it. There is a lateral surface 496, generally perpendicular to the first surface 492 and the second surface 494, and extending between the first and second surfaces 492, 494, and 496. The second surface 496 forms an outer periphery 498. In this example, the outer periphery 498 is circular. The first surface 492 and the second surface 494 can be parallel, and are generally flat (with variations), in many examples. The first and second surfaces 492, 494, and 494 can be perpendicular to the stem 64. At least a portion of the outer periphery 498 extends radially farther from the longitudinal axis 482, 682 than a radial outermost portion of the handle member 70. In many cases, the outermost dimension of the washer section 490 is equal to or greater than an outermost dimension of the handle member 70. In the example shown, the outermost dimension of the washer section 490 is greater than an outermost dimension of the handle member 70. Extending from the first surface 492 is the handle member 70. In this embodiment, the handle member 70 has a wall 500 extending from the first surface 492 of the washer section 490. The wall 500 can generally extend perpendicularly from the first surface 492. In the example shown, the handle member 70 with the wall 500 projects from the first surface 492 of the washer section 490 and without any portion of the stem 64 between the first surface 492 and the handle member 70. The wall 500 can have many different shapes. In the alternative design shown in FIGS. 21-26, which is not part of the claimed subject matter, the wall 500 is a single vertical member 512 with a free end 510 opposite the first surface 492 of the washer member 490. The vertical member 512 extends between the opposite lateral ends 514, 516 of the wall, which are perpendicular to the first surface 492. The free end 510 extends between the lateral ends 514, 516. In the alternative design shown in FIGS.21-26, which is not part of the claimed material, the wall 500 has one or more curved surfaces, whereas in the embodiment of FIGS.27-30 and the alternative design of FIG.31, which is not part of the claimed material, the wall 500 may have straight segments (described below). In FIG. 24, which is not part of the claimed subject matter, the wall 500 has a curved surface 502 and a curved surface 503. These curved surfaces 502 and 503 help give the wall 500 an S-shape between the ends 514 and 516. Many variations in the shape of the wall 500 are possible. In this example, the radius of curvature for the curved surfaces 502 and 503 is designed to allow convenient gripping and turning by a human hand. Furthermore, the wall 500 is designed to be attractive and eye-catching, as many variations in appearance are possible. While many variations are possible, the radius of curvature for the curved surfaces 502 and 503 can be in the range of 2.66 to 3.04 cm (1.05 to 1.2 in).For example, when sized within this range, one of the curved surfaces 502, 503 fits comfortably in most human thumbs and works particularly well during the installation process for use by an installer's right hand. The handle member 70 in the alternative design of FIGS. 21-26, which is not part of the claimed subject matter, further includes a plurality of ribs 506 projecting from opposite sides 508, 509 of the wall 500. The ribs 506 extend longitudinally, generally parallel to the longitudinal axis 482. The ribs 506 extend from a terminal end 510 of the wall 500 to the first surface 492 of the washer section 490. Although there may be many variations, in this example, there are between 8-15 ribs (for example, approximately 12) 506, spaced apart, on each side 508, 509 of the wall 500.The 506 ribs help to improve and enhance the grip of a human hand on the 470 handle member. The height of the wall 500 extends from the first surface 492 to the terminal end 510. The height can have many variations and, in this example, it can be greater than a stem length 64 but less than half the length of the insertion member 44. In exemplary embodiments, the outermost dimension of the washer section 490 is equal to or greater than an outermost dimension of the handle member 70, both in directions parallel and perpendicular to the central longitudinal axis 482 of the handle 70. In practice, this will ensure complete coverage of the receiving I-groove 36 when the device 424, 624 is inserted and rotated between 0 and 90 degrees to make a connection between two adjacent bands 20, 22. In the embodiment of FIGS. 27-30 and the alternative design of FIG. 31, which is not part of the claimed subject matter, the wall 500 has a plurality of connected straight sections 630 having generally flat and planar surfaces enclosing an interior 632. Many variations are possible, and in the example shown, the straight sections 630 form a polygon 634, which includes a regular polygon. The exemplary polygon 634 shown is a hexagon 636. The straight sections 630 can receive a tool, such as a wrench or a suitably shaped hexagonal socket, which can be used to turn the handle member 70. Inside polygon 634 (632), there may be an additional insert 638 (FIG. 30), recessed from the plane of the first surface 492. Insert 638 may be centered within polygon 632 and have a polygonal shape. While variations are possible, in this example, insert 638 has the same shape as wall 500. In the example shown, insert 638 is shaped like a hexagon 640. A tool can be inserted into insert 638 to rotate handle 70. The connecting device 424, 624 can be used in the system of FIG. 26, analogously to that described for FIG. 3. As can be seen, the washer section 490 is positioned against and covers the open slots 36 on the first side 40 of the cell overlap region 38. This helps prevent the migration of soil or other materials through the slot 36. In some applications, such as use with retaining walls, the connecting device 424, 624 having the washer section 490 is used only for the portion of the retaining wall that is externally visible, as it contributes to the attractiveness and beauty of the wall. In that case, the portions that are not visible can use prior art connecting devices according to US 8092122; or, alternatively, according to FIGS. 4-19. The connecting device 424 can be used in a fastening procedure to expanded cell confinement structures, as described above with respect to connecting device 24. In this case, the insertion step includes pressing the washer section 490 against the first side 40 of the overlap region 38. There is also the turning step of the handle member 70, where the handle member 70 includes the wall 500 projecting from the washer section 490. The handle member 70 can also be turned using a tool acting on polygon 634 or on insertion 638. The connecting device 424, 624 may form part of a kit for the system of FIG. 26. The connecting device 424, 624 is provided so that the washer section 490 is provided to be placed against and cover the open slots 36 on the first side 40 of the cell overlap region 38. The 424, 624 connection device can be made from a variety of materials, including non-metallic materials such as plastic (HDPE, polypropylene, etc.). The 424, 624 device can be manufactured by molding, such as injection molding. The above provides a complete description. Many implementations are possible.

Claims

1. A connecting device (24) for securing two expanded cell confinement structures (18); the connecting device (24) comprising: (a) an insertion member (44) having first and second opposing insertion ends (46, 47) and an insertion member extension (48) between them; the insertion member extension (48) including an outer face (54) oriented opposite a remaining portion of the connecting device (24), and an inner face (66) oriented toward an integral handle member (70); (b) an integral stem (64) generally extending perpendicularly from the insertion member extension (48) and being separated from each of the ends (46,47) first and second insertion ends; intersecting the stem (64) and the inner face (66); (c) the integral handle member (70) extending from the stem (64) at an end of the stem (64) away from the insertion member (44); and (d) a plurality of burrs (200) projecting from the insertion member (44), the plurality of burrs (200) including at least two burrs (204, 206; 205, 207) projecting from the inner face (66) on each of the opposite sides of the extension (48) of the insertion member toward the handle member (70).

2. A connecting device (24) according to claim 1, wherein: (a) the first and second insertion ends (46, 47) join the outer face (54) and the inner face (66); (b) the first insertion end (46) has a first flat end face (67); and (c) the second insertion end (47) has a second flat end face (68).

3. A connecting device (24) according to claim 2,where: (a) the outer face (54) includes a first angled section (56); a second angled section (57); and a straight middle section (55) extending between the first angled section (56) and the second angled section (57); (i) the first angled section (56) extending from the first insertion end (46) to the middle section (55) at a non-zero angle (β); and (ii) the second angled section (57) extending from the second insertion end (47) to the middle section (55) at a non-zero angle (β).

4. A connecting device (24) according to claim 2, wherein the inner face (66) has a first portion (211) and a second portion (212); (a) the first portion (211) being between the first insertion end (46) and the stem (64); (b) the second portion (212) being between the second insertion end (47) and the stem (64); (c) the plurality of burrs (200) including at least two burrs (204,206) extending from the first portion (211) into the handle member (70); and (d) the plurality of burrs (200) including at least two burrs (205, 207) extending from the second portion (212) into the handle member (70).

5. A connecting device (24) according to any one of claims 1-4, wherein the handle member (70), the insertion member (44), and the stem (64) are a single, solid piece.

6. A connecting device (24) according to any one of claims 1-5, wherein: (a) the handle member (70) has first and second handle ends (72, 73) and a handle member extension (74) between them; the stem (64) being separate from each of the first and second handle ends (72, 73); and (b) the handle member extension (74) includes first and second rounded lugs (76, 77) projecting therefrom.

7. A connecting device (24) according to claim 6, wherein the lugs (76,77) first and second protruding from the insertion member (44) at the first and second handle ends (72, 73), and the handle member extension (74) is straight between the first and second lugs (76, 77).

8. A connecting device (24) according to claim 1, further comprising: (a) a longitudinal shaft (240) extending through each of the insertion member (44), the handle member (70), and the stem (64); and (b) a washer section (490) between the handle member (70) and the insertion member (44); (i) the washer section (490) having a first surface (492) and an opposing second surface (494); (ii) a lateral surface (496) extending between the surfaces (492,494) first and second; the lateral surface (496) being along an outer periphery (498); and (iii) at least a portion of the outer periphery (498) extending radially from the longitudinal axis (240) at a distance equal to or greater than a radial outermost portion of the handle member (70).

9. A connecting device (24) according to claim 8, wherein at least a portion of the first surface (492) and of the second surface (494) of the washer section (490) is perpendicular to the handle member (70).

10. A connecting device (24) according to any of claims 8 and 9, wherein an outermost dimension of the washer section (490) is equal to or greater than an outermost dimension of the handle member (70).

11. A connecting device (24) according to any of claims 8-10, wherein the handle member (70) has a wall (500) extending from the first surface (492) of the washer section (490),11. A connecting device (24) of claim 11, wherein the wall (500) of the handle has the form of a regular polygon (634).

12. A connecting device (24) of claim 8, wherein the handle member (70) has a wall (500) extending from the first surface (492) of the washer section (490), the wall (500) having one or more curved surfaces (502, 503).

13. A connecting device (24) of claim 8, wherein the handle member (70) has a wall (500) extending from the first surface (492) of the washer section (490), the wall (500) having one or more curved surfaces (502, 503).

14. A connecting device (24) of any of claims 12 and 13, further including a plurality (506) of ribs projecting from sides (508,509) opposite the wall (500).

15. A kit comprising: (a) a plurality of unit cell bands (18) made of elongated plastic strips (26) joined together in separate areas (28); the strips (26) forming cell walls (30) (32); at least some of the cells (32) defining open slots (36) that can be aligned with open slots (36) of unit cell bands (18) placed adjacently in cell overlap regions (38), the cell overlap regions (38) having first sides (40) and second sides (42) opposite each other; and (b) a plurality of connecting devices (24) usable for fastening together unit cell bands (18) placed adjacently across the slots (36) in the cell overlap regions (38); each of the connecting devices (24) which includes: (i) an insertion member (44) having ends (46,47) opposing first and second insertion members and an insertion member extension (48) between them; the insertion member (44) being positioned on the second side (42) of the cell overlap region (38); (A) a plurality of burrs (200) projecting from the insertion member (44) and being positioned towards the first side (40) of the cell overlap region (38); (ii) an integral stem (64) generally extending perpendicularly from the insertion member extension (48) and being separated from each of the ends (46,47) first and second insertion; (A) the stem (64) being positionable through the cell overlap region (38) extending through aligned grooves (36); and (iii) an integral handle member (70) generally extending perpendicularly from the stem (64) at one end of the stem (64) away from the insertion member (44); and (A) the handle member (70) being positionable on the first side (40) of the cell overlap region (38).

Images