Abstract:
A landscape edging system includes an elongate edging strip having first and second mutually perpendicular plate-like members forming an L-shape. The first plate-like member extends coextensively with the second plate-like member and is configured to lie parallel with an upwardly facing surface of a landscaping surface upon which it has been placed. A further plate-like member is oriented either above or below the first plate-like member. Plural fastening members fasten the first plate-like member to the further plate-like member to facilitate clamping of a porous material layer therebetween to facilitate a fixed orientating of the edging strip relative to the landscape surface on which the edging strip has been placed.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Application Ser. No. 61/190,858, filed Sep. 3, 2008, which is incorporated herein by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to an edging strip for use in various landscaping environments, particularly those that do not permit the use of anchors for anchoring the edging strip to a supporting surface directly beneath the edging strip. 
       BACKGROUND OF THE INVENTION 
       [0003]    This invention arose in an environment where vegetation is located on roofs of structures, which applications are known in the field as green roof applications. In these environments, it is often not possible to secure edging strips directly to the building roof for fear of damaging the roofing surface causing leakage of water through the roof into the interior of the building. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]    Other objects and purposes of this invention will be apparent to persons acquainted with apparatus of this general type upon reading the following specification and inspecting the accompanying drawings, in which: 
           [0005]      FIG. 1  is an isometric view of the edging strip embodying the new invention; 
           [0006]      FIG. 2  is a top view thereof; 
           [0007]      FIG. 3  is an edge view of the edging strip; 
           [0008]      FIG. 4  is an isometric view of an arcuate formation of the edging strip; 
           [0009]      FIG. 5  is an isometric view of an inside corner formed by the edging strip; 
           [0010]      FIG. 6  is an isometric view of an outside corner formed by the edging strip; 
           [0011]      FIG. 7  is an isometric view of an edging strip embodying the invention being used with a geo grid fabric; 
           [0012]      FIG. 8  is a side view of a pair of edging strips that are connected end to end; 
           [0013]      FIG. 9  is an alternate environment for the inventive edging strip; 
           [0014]      FIG. 10  is an isometric view of the edging strip embodying the invention and a plate clamping the porous material layer (geo grid) therebetween; 
           [0015]      FIG. 11  is an isometric view of a modified capture plate operatively connected to the edging strip and the porous or geo grid layer; 
           [0016]      FIG. 12  is an isometric view of a further modified capture plate; 
           [0017]      FIG. 13  is an isometric view of a further modified capture plate; 
           [0018]      FIG. 14  is an isometric view of a still further modified capture plate; and 
           [0019]      FIGS. 15-18  are each an isometric view of the respective modified capture plates of  FIGS. 11-14  but with plural upstanding barbs on one face of the respective capture plate. 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    A portion of a section of elongated edging strip  10  made of extrudable or similar formable material, such as but not limited to aluminum, and embodying the invention is illustrated in the drawings. The edging strip  10  has an L-shape which includes a generally horizontal plate-like base leg member  11  and a vertically upstanding plate-like leg member  12  oriented approximately 90° to the base leg. The base leg  11  and the vertical leg  12  have ribbing thereon forming raised sections  13  and recessed sections  14  extending coextensively with the length of each section of edging strip. 
         [0021]    Adjacent the terminal edge  16  of the base leg  11  there is provided a channel  17  defined by upstanding wall sections  18  and  19 . The wall section  18  has a generally horizontally extending flange  21  extending toward the wall section  19  parallel to the plane of the base leg. Similarly, the wall section  19  has a generally horizontally extending flange  22  extending toward the wall section  18  parallel to the plane of the base leg. In this particular embodiment, the floor  23  of the channel  17  has a raised section  13  therein that occupies a majority of the floor space. 
         [0022]    Adjacent the terminal edge  24  of the vertical leg  12  there is provided a channel  26  defined by upstanding wall sections  27  and  28 . The wall section  27  has a generally vertically extending flange  29  extending toward the wall section  28  parallel to the plane of the vertical leg. Similarly, the wall section  28  has a generally vertically extending flange  31  extending toward the wall section  27  parallel to the plane of the vertical leg. In this particular embodiment, the floor  32  of the channel  26  may have a raised section  13  therein that occupies a majority of the floor space dependent upon the size of the profile. 
         [0023]    The bottom facing surface  33  of the base leg  11  and the leftwardly ( FIG. 3 ) facing surface  34  of the vertical leg of the L-shaped edging strip  10  each have serrated surfaces as at  36 . While the serrations may be of any convenient style, the serrations  36  in this particular embodiment are longitudinally extending, closely spaced, scorings  37  or any abrasive configuration. The scorings  37  are oriented on surface segments that are opposite the sides of the channels  17  and  26 . 
         [0024]      FIG. 1  illustrates a plurality of side by side through openings  38  provided in the vertical leg  12  adjacent the juncture with the base leg  11 . The openings  38  each have a cathedral-like window shape, namely, a shape where the bottom edge of the opening is straight, the side edges of the opening are straight and the upper edge portion is arch-like. Furthermore, the cross sectional size of these openings are controlled so that a plurality of them per foot of length will allow a certain volume of water to pass therethrough, such as 15 gallons per minute. 
         [0025]    The base leg  11  is configured with a plurality of material removed therefrom as by a stamping process. More specifically, the base leg  11  includes a plurality of rectangular openings  39  wherein each of the openings abuts the juncture with the vertical leg  12 . Each of the openings  39  is spaced in a lengthwise direction a distance from one another by a base leg section  41  that extends to the distal edge  16 . Each of the openings  39  has a pair of transversely extending slot sections  42  and  43  that each terminate in a V-shaped wall section  44 . The base leg  11  is furthermore provided with transversely extending slots sections  46  and  47  that are aligned with the slot sections  42  and  43 . The slot sections  46  and  47  are open ended at the distal edge  16  of the base leg. The other ends of the slot sections  46  and  47  terminate in a V-shaped wall section  49 . The lateral space between the slot sections  46  and  47  is defined by a base leg section  51 . The transverse distance between the apexes of the V-shaped wall sections  44  and  49  is controlled so as to permit the base leg sections  51  to be manually grasped and flexed upwardly and downwardly relative to the plane of the base leg  11  so as to twist the base leg material to a point of failure allowing the base leg sections  51  to be removed as shown in  FIG. 4 . 
         [0026]    In the embodiment best illustrated in  FIG. 2 , each of the base leg sections  41  has at least one through hole  52 . While the edging strip  10  is capable of use without anchoring spikes or anchors, it is sometimes preferable to insert anchoring spikes or anchors into selected ones of the holes  52  to anchor the edging strip  10  to a supporting surface to prevent movement of the edging strip relative to the supporting surface. 
         [0027]      FIG. 3  illustrates the provision of a waterproof membrane  54  made of a polymer, such as rubber. The membrane  54  is placed onto a roof surface  56  in applications known as “green roof” applications. The edging strip  10  embodying the invention is thereafter placed onto the upwardly facing surface  57  of the membrane  54  so as to cause the upper surface of the membrane to conform to the shape of the serrations  36  to serve the purpose of preventing the edging strip  10  from moving laterally relative to the membrane. 
         [0028]    When some or all of the base leg sections  51  are manually removed in the field as depicted in  FIG. 4 , the vertical leg  12  can be formed into an arc. 
         [0029]    The base design is specifically configured to allow the base leg sections  51  to be removed manually eliminating the need to use a saw or other cutting device on the roof surface which may produce metal shavings, chips, scrap or other debris capable of damaging the integrity of the roof membrane. 
         [0030]    When selected base leg sections  41  and  51  have been manually removed in the field as depicted in  FIG. 5 , the vertical leg  12  can be formed into what is known in the field as an inside angle, an angle of 90° being illustrated in  FIG. 5 . Similarly, the vertical wall  12  can be formed into what is known in the field as an outside angle, an angle of 90° being illustrated in  FIG. 6 . 
         [0031]      FIG. 7  illustrates an application where a conventional geo grid fabric  58  is used in a situation where it is desired to anchor one edge of the fabric (not shown) under the ballast material or to a fixed member and overlaying the opposite edge of the fabric over the upper surface, or under the surface, of the base leg  11  of the edging strip  10  as depicted in  FIG. 7 . In the alternative ( FIG. 10 ), the porous material layer or geo grid material  58  can be clamped between a base (stem)  11  of the restraint  11  and an elongate capture plate  70  extending coextensively with the restraint  11 . Plural self-tapping screws  60  are utilized for drawing the plate  70  and the base  11  together to clamp the porous material layer or geo grid material therebetween. It is to be recognized that the plate  70  can be oriented above the base  11  or below it (as shown in  FIG. 10 ) in order to achieve a stable connection of the geo grid material to the edge restraint  11  so as to provide a stable orientation of the restraint relative to the ground or bed upon which the restraint and porous material layer or geo grid material are place. 
         [0032]    In the alternative, a fastening or capture plate  70  ( FIG. 7 ) can be used to trap or clamp the porous material layer or geo grid fabric to the base leg  11 . A fastening member, such as a conventional nut and bolt, is used by inserting the bolt  59  from the bottom side of the base leg  11  up through a selected hole  52  to penetrate the fabric and a hole in the capture plate  70 . The nut  61  is secured to the bolt  59  to trap or clamp the fabric between the base leg  11  and the fastening plate or member. 
         [0033]    A pair of mutually adjacent ends, such as depicted in  FIG. 8 , of two adjacent edging strips  10  can be secured together utilizing an elongate connector bar  65  which is configured to be received into axially aligned channels  26  in the adjacent vertical legs  12 . If desired, a further elongate connector bar  63  is configured to be received into axially aligned channels  17  in the adjacent base legs  11 . As the ends of the adjacent edging strips  10  are brought together, a tool can be used to deform or cold work one or more deformations into the respective connector bars  62  and  63  and the floors  23  and  32  to interlock the bars and floors together to prevent a relative movement between the connector bars  62  and  63  and the respective channels  17  and  26 . 
         [0034]    Once the edging strips  10  have oriented end to end so that the side of the vertical legs  12  remote from the base legs  11  form a barrier or an edge for growing media for plant life, ballast in the form of non-compactable material in the form of growing media, stone and the like is placed onto the upper surface of the base leg  11  to force the serrations into the material of the membrane  54  that is secured to the roof to cause the edging strip to become incapable of relative lateral movement with respect to roof surface. In installations of this type, the base leg  11  is variable from about 2 inches up to 12 or more inches in length dependent upon specific application and the vertical leg is also variable from about 2 inches up to 12 or more inches in height again dependent upon the specific application requirements. 
         [0035]    This invention also has other applications not associated with green roof applications, such as porous pavement applications. More specifically, to date the approach to retention of porous pavement installation is a heavy poured concrete curb. Although it&#39;s performance is relatively acceptable, this methodology has significant drawbacks.
       1. A porous pavement installation utilizing poured concrete curb takes considerably longer in that the curb must be formed, allowed to cure, followed by removal of the forms. This delay of at least two to three days forces the contractor to either remove his excavation equipment from the site or retain it on site potentially sitting idle. This chronological extension of the installation process unduly increases the cost of the installation.   2. Layered installation of the aggregate materials following the forming of the poured concrete curb creates a delicate balance between effectively vibra-compacting of the aggregate several times using heavy equipment and this vibratory compaction process damaging the concrete curb designed to retain it. The proper amount of time needed to fully cure concrete is not achieved prior to the vibratory layered installation of the aggregate.   3. The nature of porous “open-graded” base materials (crushed stone with no small or fine particles) is that regardless of the initial attempts at compaction, settling will occur over the life of the installation. The drawback to poured concrete curb which is poured over undisturbed or fully compacted adjacent parent material is that it will inevitably result in uneven rates of settling or movement where the pavement surface and poured concrete curb or other restraint requiring anchoring into undisturbed or fully compacted adjacent material meet. An uneven rate of movement may also be caused by frost heave producing movement of the curb or restraint installed or anchored into adjacent material independent of the porous pavement surface.   4. It results in an unsightly heavy border, visually undesirable in many applications.       
 
         [0040]    This system is installed in process following excavation and the majority of the vibratory installation processes;
       1. Significantly lessening the time required for the installation process, resulting in significant cost reductions.   2. Serves as a horizontally integrated system acting in concert with the active function of the system.   3. Floats independently as part of a dynamic system as opposed to a fixed, inflexible, independent perimeter device.   4. The perimeter location of the restraint system is not restricted to the edge of the installation where compacted “open-graded” base material meets the undisturbed adjacent landscape. Perimeter location of my restraint is not necessary for anchoring or securing in place. This freedom to locate the perimeters of the porous paver roadways or walkways at any location over the subsurface water system, be it natural or man made, vastly increases the design flexibility between these two elements.       
 
         [0045]    A free floating Dead Man system that is installed on and captured by non-compactable aggregate materials. 
         [0046]    The interface between an inner retention structure (optional), geotextile grid and an outer restraint that work in concert with each other. 
         [0047]    Conventional Dead Man systems derive their effectiveness by incorporating compactable overbearing materials of sufficient enough depth, weight and compactibility to serve as a continuous lateral/horizontal retention mechanism. In most cases, the inner anchoring structure relies almost exclusively on its ability to retain itself by vertically anchoring itself into undisturbed or significantly compactable disturbed soil. 
         [0048]    This invention sometimes can benefit neither from the weight, depth or compactibility given the relative minimal overlying depth resulting in minimal overbearing weight and inherent non-compactibility of materials used. In addition, the non-compactable nature of the aggregate that my system is installed over negates any effective opportunity for vertical anchoring associated with either the inner or outer restraint structure. 
         [0049]    Effective vertical system stability coupled with horizontal retention and stability in the retention and integrity of the overlying load bearing surface is the ultimate goal. This system achieves this goal within an environment where layers of “open-graded” base material (crushed stone layers with no small or fine particles) of uniform size are load bearing yet porous. The load bearing yet porous nature of the “open-graded” base material prohibits effective anchoring with conventional downward perimeter anchoring such as spikes. The integral functioning of my system effectively interfacing surface material (pavers), “open-graded” base material, geo grid, and restraint allows the macro goal for the installation of rapid downward and horizontal permeability of surface water. 
       Alternate Capture Plate Construction 
       [0050]    Several modifications of the capture plate  70  shown in  FIGS. 7 and 10  are illustrated in  FIGS. 11-18 . 
         [0051]    In  FIG. 11 , the modified capture plate  71  has an upstanding lip  72  along one edge. The porous layer or geo grid layer  58  is placed between the upper surface of the capture plate  71  and the understand of the base leg  11  of the edging strip and an edge  58 A of the porous layer of geo grid layer is wrapped over the edge of the base leg  11  and overlays the upwardly facing surface of the base leg as shown in  FIG. 11 . Plural self-tapping screws  60  are utilized to secure the base leg  11  to the capture plate  71 . The upstanding lip  72  serves to prevent relative movement between the edging strip  10  and the porous layer or geo grid layer.  FIG. 13  is similar to  FIG. 11  except that the lip  72  is separated into multiple upstanding lips  72 A configured to enter the open spaces provided in the porous layer or geo grid layer. In the  FIG. 13  embodiment, the porous layer or geo grid layer does not overlay the upper surface of the base leg  11  of the edging strip. 
         [0052]    In  FIG. 12 , the modified capture plate  81  has an upstanding lip  82  along one edge. The upper edge of the lip  82  has a flange  83  extending generally parallel to a plane containing the capture plate  81  and toward the vertically upstanding leg  12  of the edging strip  10 . The porous layer or geo grid layer  58  is placed between the upper surface of the capture plate  81  and the understand of the base leg  11  of the edging strip and an edge  58 A of the porous layer of geo grid layer is wrapped over the edge of the base leg  11  and overlays the upwardly facing surface of the base leg as shown in  FIG. 12 . Plural self-tapping screws  60  are utilized to secure the base leg  11  to the capture plate  81 . The upstanding lip  82  and flange  83  serve to prevent relative movement between the edging strip  10  and the porous layer or geo grid layer  58 .  FIG. 14  is similar to  FIG. 12  except that the lip  82  and flange  83  configuration depicted in  FIG. 12  is separated into multiple upstanding lips  82 A and flanges  83 A in  FIG. 14 , each configured to enter the open spaces provided in the porous layer or geo grid layer. In the  FIG. 14  embodiment, the porous layer or geo grid layer  58  does not overlay the upper surface of the base leg  11  of the edging strip  10 . 
         [0053]      FIGS. 15-18  each illustrate a modified capture plate that is similar to the capture plates  71  and  81  illustrated in  FIGS. 11-14 . The upper facing surface  86  of each of the modified capture plates  71 A and  81 A have plural upstanding barbs  87  or the like that are configured to intermesh with the porous layer or geo grid layer  58  to further prevent relative movement between the edging strip  10  and the porous layer or geo grid layer  58 . 
         [0054]    It is to be understood that the capture plates can be positioned above the upper surface of the base leg  11  of the edging strip  10  and oriented so that the respective lips project downwardly through the open space in the porous or geo grid layer  58 . Plural self-tapping screws would also be utilized to secure the capture plates to the respective base leg  11  of the edging strip  10 . 
         [0055]    Although a particular preferred embodiment of the invention has been disclosed in detail for illustrative purposes, it will be recognized that variations or modifications of the disclosed apparatus, including the rearrangement of parts, lie within the scope of the present invention.