Abstract:
Materials and structures for absorbing energy. The materials and structures are well suited for arresting aircraft and other vehicles, although their purposes need not be so limited. Also detailed are packaging and other solutions for maintaining system integrity, especially (but not exclusively) when foam glass or other aggregate is employed and stabilizing the location of the aggregate is desired.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 13/604,787, filed on Sep. 6, 2012, the entire contents of which are hereby incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to aggregates, materials, and other structures and more particularly, but not necessarily exclusively, to vehicle arresting systems in which aggregates, materials, or other structures are used to absorb energy to effect vehicle arrests. 
       BACKGROUND OF THE INVENTION 
       [0003]    Commonly-owned U.S. Pat. No. 7,597,502 to Allen, et al. (the “Allen Patent”), discloses use of compressible material such as ceramic or phenolic foam or cellular concrete to assist in arresting vehicles. The compressible material may, if desired, be formed into blocks or beds of particular compressive gradient strength. Fabric, film, or other wrappings may surround at least portions of the blocks, with “[a] basic function of [the wrappings being] to aid in maintaining structural integrity” of blocks “during non-emergency conditions, while being subject to tearing, breakage or other partial or complete disintegration during an arresting incident.” See Allen Patent, col. 4,11. 43-48. 
         [0004]    U.S. Patent Application Publication No. 2012/0057931 of Narmo (the “Narmo Application”) similarly discloses use of foamed glass aggregate for vehicle arrestments. Systems of the Narmo application include beds filled with foam glass aggregate as well as “top cover[s].” As defined in the Narmo Application, a “top cover” comprises “any cover . . . which will prevent the aggregate mass [from being] contaminated or filled with air-borne particulates, subject to plant growth, or [subject to] other environmental impacts which [interfere] with the performance of the foamed glass aggregate mass.” See Narmo Application, p. 2, col. 2, ¶ 0028. 
       SUMMARY OF THE INVENTION 
       [0005]    Unclear is whether any “top cover” of the Narmo application will be satisfactory to maintain structural integrity of its corresponding aggregate bed. The present invention thus provides partial or complete “packaging” and other solutions for maintaining bed integrity, especially (but not exclusively) when glass or other aggregate is employed. As a non-limiting example, moldable bags may contain aggregated particles, with the bags being capable of being assembled into a bed. Alternatively, particles may be embedded in an adhesive or other binder, encased by a box, or anchored to a roof, ceiling, or other structure. 
         [0006]    At least one version of the invention may include geotextile covers and generally vertically-extending anchors. In this embodiment, particles of foam glass or other material may form a bed covered in whole or part by a geotextile cover in the form of mesh or a net, for example. Vertical rods or other structures may serve as anchors, connecting the cover to the foundation of the bed or elsewhere as appropriate. Such anchors may be made of breakable or deformable material so as not unduly to impede vehicle arrestments. 
         [0007]    In other versions of the invention, at least some of the particles may be placed within boxes or bags (whether moldable or not). If the bags are adhered or attached to covers and foundations of beds, the bags themselves may help anchor the covers in lieu of, or in addition to, rods or other structures. Preferred bags may be formed of open-net, frangible material, although other types of materials may be employed instead. 
         [0008]    Whether or not bagged, aggregate may be placed within cubicles or other structures having floors and, if desired, upstanding walls. In at least some embodiments of the inventions, upper edges of walls may be folded to create flanges to facilitate attachment to covers. Such a structure reoriented one-hundred eighty degrees (i.e. positioned upside-down) may have its flanges attach to foundations. In some cases aggregate may be adhered to the floors of the cubicles or other structures. 
         [0009]    Alternatively or additionally, loose aggregate may be mixed with adhesives or binders to form bricks or other integrated units. Such adhesives preferably are non-cementicious, with presently-preferred binders including chemically bonded phosphate ceramic (CBPC), asphalt, or polymeric mixes (e.g. epoxy) with filler components such as fly ash, slag, ground glass, etc. Sizes and shapes of the units may change as needed for satisfactory installation; the units may be stacked as part of a bed with or without gaps between them, and adjacent units may, but need not necessarily, be adhered or attached to each other. They likewise optionally may be placed within cubicles or other structures and adhered to their floors. 
         [0010]    Moreover, any such mixing of loose aggregate and binders may occur in situ if appropriate. This sort of “cast in place” technique could expedite bed formation, with the mixing occurring on site and the mix immediately being poured (as, e.g., slurry) into beds. Thereafter, it may set or cure in the beds. Casting may occur in one or more layers, with or without fabric or other dividers between layers. 
         [0011]    Alternate deformable materials may include other types of open-cell or closed-cell ceramics in lieu of foam glass. If needed, structures including open-cell ceramics may, for example, be coated or otherwise covered with water-impermeable (or water-resistant) material. One such coating itself may be non-porous ceramic; alternatively, other coatings or coverings may be employed. Yet another deformable material may be or include aerated autoclaved concrete (AAC), phosphate-bonded cellular composite, alkali-activated cellular fly ash, or cellular polymers. 
         [0012]    Solar- or other-powered heating systems including heating elements, channels, conduits, or vents may be included in or adjacent to beds in certain cold climates. For airports lacking jet service (so beds will not be subject to jet blast), loose or bagged aggregate or other material may be used either without any covering or with low-strength netting or coatings. Alternatively, the aggregate or other material may be covered by asphalt—in essence as a continuation of the runway, albeit with the asphalt being of sufficiently low strength to assist in effecting vehicle arrestment as needed. Beds may be self-draining or include drain piping or tunnels and may include expansion joints if needed. 
         [0013]    It thus is an optional, non-exclusive object of the present invention to provide energy-absorbing materials and structures. 
         [0014]    It is another optional, non-exclusive object of the present invention to provide materials and structures for effecting vehicle arrests. 
         [0015]    It is also an optional, non-exclusive object of the present invention to provide “packaging” and other solutions for maintaining bed integrity when aggregate is employed as energy-absorbing material. 
         [0016]    It is a further optional, non-exclusive object of the present invention to provide techniques for casting energy-absorbing materials in place. 
         [0017]    It is, moreover, an optional, non-exclusive object of the present invention to provide supports, cubicles, or other structures for energy-absorbing materials. 
         [0018]    Other objects, features, and advantages of the present invention will be apparent to those skilled in the relevant art with reference to the remaining text and the drawings of this application. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]      FIG. 1  is a schematicized representation of an exemplary bed of the present invention. 
           [0020]      FIG. 2  is a schematicized representation of an exemplary bed of the present invention. 
           [0021]      FIG. 3  is a mock-up of exemplary components of a bed of the present invention. 
           [0022]      FIG. 3A  is a perspective view of exemplary components of a bed similar to those of  FIG. 3 . 
           [0023]      FIG. 3B  is a cross-sectional view of bed components of  FIG. 3A . 
           [0024]      FIG. 4  is a mock-up of exemplary components of a bed of the present invention. 
           [0025]      FIG. 4A  is a cross-sectional view of bed components similar to those of  FIG. 4 . 
           [0026]      FIG. 5  is a schematicized representation of exemplary components of a bed of the present invention. 
           [0027]      FIG. 6  depicts an exemplary loose material adhered with or to a binder or support to form a unit. 
           [0028]      FIG. 6A  provides another depiction similar to  FIG. 6 . 
           [0029]      FIG. 7  depicts an exemplary loose material adhered with a binder and positioned within a cubicle. 
           [0030]      FIG. 7A  provides another depiction similar to  FIG. 7 . 
           [0031]      FIGS. 8A-B  are schematicized representations of a unit including (only) an upper covering or coating ( FIG. 8A ) or both upper and side coverings or coatings ( FIG. 8B ). 
           [0032]      FIG. 9  is a schematicized representation of a third exemplary bed of the present invention. 
           [0033]      FIGS. 10A-B  are schematicized top ( FIG. 10A ) and plan ( FIG. 10B ) views of an exemplary bed of the present invention. 
           [0034]      FIGS. 11A-B  and  12 - 13  are schematicized views of exemplary techniques for casting materials in place. 
           [0035]      FIGS. 14A-C  are schematicized views of exemplary components of a bed of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0036]      FIG. 1  illustrates, in schematic form, an exemplary bed  10  of the present invention. Bed  10 , and any other bed mentioned herein, may extend above-grade, below-grade, or both above- and below-grade as desired. Shown in  FIG. 1  is grade or surface S, with at least part of bed  10  extending above the surface S. If bed  10  is designed (at least principally) for effecting arrests of fixed-wing aircraft, surface S advantageously may be a runway or taxiway. 
         [0037]    Bed  10  may contain at least deformable material  14 , roof or cover  18 , and anchors  22 . Material  14  may be or comprise aggregate in the form of foam glass particles as per the Narmo application. Alternatively or additionally, material  14  may be or comprise other permanently or temporarily deformable material. Material  14  beneficially does not sustain fire, consistent with guidelines of the U.S. Federal Aviation Administration. 
         [0038]    Absent cover  18 , at least some material  14  forming bed  10  may be exposed to jet blast, wind, or other conditions that may cause scattering of the material  14 . Accordingly, cover  18  may serve to confine material  14  existing at or above grade. Cover  18  beneficially is deformable when subjected to weight of a to-be-arrested vehicle; a presently-preferred—but not exclusive—form of cover  18  may be a geotextile such as a plastic net whose mesh is smaller than the majority of any loose particles forming material  14 . 
         [0039]    One or more anchors  22  may serve to secure cover  18  in position relative to material  14 . Anchors  22  may attach or adhere to cover  18  and extend generally vertically through bed  10  to the ground or other foundation supporting bed  10 , mooring the cover  18  to the foundation. As depicted in  FIGS. 14A-C , possible anchors  22  may comprise lengths of plastic pipe  26  and optional quick-release or breakaway connectors  30  and discs  34 . Pipe  26  preferably deforms when subjected to weight of a to-be-arrested vehicle so as not to impede an arrest, while discs  34 , if present, may help stabilize anchors  22  from moving inside the aggregate due to vibrations or other forces. 
         [0040]    Illustrated in  FIG. 2  is an alternate bed  100  of the present invention. Like bed  10 , bed  100  may include material  14  and cover  18 . It likewise may include anchors  22  if desired. Unlike bed  10 , however, bed  100  may include bags  38 , boxes, or other containers of material  14  rather than, or in addition to, loose aggregate. Containing material  14  in this manner should reduce sliding or other undesired movement of the material  14 . Moreover, if bags  38  extend from the foundation of bed  100  to cover  18 , as shown in  FIG. 2 , they may be adhered or attached to the foundation and cover  18  as additional or alternative anchors. Although  FIG. 2  illustrates each bag  38  as extending the height of bed  100 , multiple shorter bags  38  may be connected together to extend over that height instead. 
         [0041]      FIG. 3  details a mock-up of an exemplary support structure  42  for material  14 . Structure may include base  46  and upstanding walls  50 , the latter of which intersect to form cubicles  54 . Loose aggregate of material  14  may be placed within the cubicles  54  to reduce further opportunity for the material  14  to move undesirably within a bed. Additionally, walls  50  may include flanges  58  to facilitate attachment to cover  18 .  FIG. 4  illustrates a similar structure  42 ′ in which material  14  is contained both within a bag  38  and a cubicle  54 , the combination of which yet further reducing undesired movement of the material  14  within a bed. 
         [0042]    Material  14  may comprise a mixture of, for example, aggregate and binder solidified to form an integrated brick, block, or unit  62 . Alternatively, material  14  may be glued or otherwise adhered to base material  66  to form an integrated unit  62 ′ (see  FIG. 6 ). In either circumstance, units  62  (or  62 ′) may be stacked as part of a bed, without or without gaps between individual units  62  (or  62 ′).  FIG. 5  shows units  62  stacked with gaps. Although two rows of units  62  are illustrated, more or fewer may be included in a bed. Similarly, although multiple units  62  of uniform size and shape are depicted in  FIG. 5 , size or shape (or both) of an individual unit  62  may differ from that or those of adjacent or nearby units  62 . Units  62  also may be adhered or attached to one another at points of contact, although such adhering or attaching is not mandatory. 
         [0043]    In one version of unit  62 ′ of  FIG. 6 , material  14  preferably is foam glass, while base material  66  preferably is asphalt. Of course, persons skilled in the art will recognize that other materials may be used instead. Because even units  62  and  62 ′ may be further confined to maintain bed integrity,  FIG. 7  shows exemplary units  62  within cubicles  54  of support structure  42 ′. 
         [0044]    Units  62  or  62 ′ may be coated on any or all of top, side, or bottom surfaces to improve various characteristics (see  FIGS. 8A-B ). In particular, waterproofing coatings may be beneficially added to units  62  or  62 ′. Such coatings could be ceramics, plastics, or otherwise as appropriate. Alternatively, wafers of such materials may be adhered or attached to the units. Indeed, foam glass itself (albeit preferably of higher density) could be used as a ceramic coating or wafer. 
         [0045]      FIG. 9  depicts yet another bed  200  lacking any cover  18 . Rather, bed  200  may be formed by spreading asphalt across surface S and adhering material  14  or containers thereof such as bags  38  to the asphalt. Although cover  18  is not required in connection with bed  200 , it nonetheless may be present if desired. 
         [0046]      FIGS. 10A-B  schematically depict bed  300 . In addition to material  14 , bed  300  may include elements or components for its heating. These elements or components may be especially beneficial when bed  300  is installed in cold climes, as extreme temperatures conceivably could impact performance characteristics of the bed  300 . 
         [0047]    Any type of heating may be utilized with bed  300 .  FIGS. 10A-B , however, illustrate one exemplary technique for non-electrical heating of the bed  300 . Consistent with this technique, one or more pipes  70  with vents could be installed in a foundation and communicate with a source  74  of forced hot air. As the forced hot air moves through the pipes, it heats bed  300  from the foundation upward (as the hot air exiting the vents rises). Accumulated snow and ice melted by the hot air may then travel downward and exit the area of bed  300  by suitable sloping of the surrounding terrain. If material  14  is not sealed, the hot air may exit bed  300  via fissures or gaps in the material  14 . By contrast, if material  14  is sealed, an exit might need to be created for the hot air. 
         [0048]    Rather than bagging, boxing, or otherwise containing material  14  in advance of forming a bed, material  14  may be cast in place in some instances.  FIGS. 11A-B  and  12 - 13  schematically illustrate some casting-in-place methods, with slurries of material  14  being dumped or sprayed into a bed, for example. In any of these methods, material  14  may be fixed into a monolithic structure, or formed into multiple layers, or formed into multiple blocks, or otherwise formed, with or without fibers, fabric, or other materials or substances interspersed therein. 
         [0049]    The foregoing is provided for purposes of illustrating, explaining, and describing embodiments of the present invention. Further modifications and adaptations to these embodiments will be apparent to those skilled in the art and may be made without departing from the scope or spirit of the invention. Indeed, multiple revisions may be made to embodiments identified in this application consistent with the concepts of stabilizing materials used as part of vehicle-arresting systems. Any terms of direction and relative positioning (e.g. upper, lower, upward, etc.) are used to identify nominal or preferred, rather than absolute, relationships of components and may be modified as appropriate. Finally, the contents of the Allen Patent and the Narmo Application are incorporated herein in their entireties by this reference.