Abstract:
Energy absorbing wall assemblies, structures including energy absorbing wall assemblies, methods of making energy absorbing wall assemblies, and methods of utilizing energy absorbing wall assemblies are disclosed herein. In some embodiments, energy absorbing wall assemblies may include a first self-supporting wall structure, a second self-supporting wall structure, and an energy absorbing filler material positioned between the first self-supporting wall structure and the second self-supporting wall structure. In additional embodiments, methods of making an energy absorbing wall assembly may include assembling a first self-supporting wall structure, and assembling a second self-supporting wall structure defining a space between the first self-supporting wall structure and the second self-supporting wall structure. The methods may further include flowing an energy absorbing filler material into the space between the first self-supporting wall structure and the second self-supporting wall structure.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/303,917, filed Feb. 12, 2010, the disclosure of which is hereby incorporated herein in its entirety by this reference. 
     
    
     BRIEF SUMMARY 
       [0002]    In some embodiments, energy absorbing wall assemblies may include a first self-supporting wall structure, a second self-supporting wall structure, and an energy absorbing filler material positioned between the first self-supporting wall structure and the second self-supporting wall structure. 
         [0003]    In additional embodiments, methods of making an energy absorbing wall assembly may include assembling a first self-supporting wall structure, and assembling a second self-supporting wall structure defining a space between the first self-supporting wall structure and the second self-supporting wall structure. The methods may further include flowing an energy absorbing filler material into the space between the first self-supporting wall structure and the second self-supporting wall structure. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0004]      FIG. 1  shows an isometric view of a portion of an energy absorbing wall assembly, according to an embodiment of the present invention. 
           [0005]      FIG. 2  shows an isometric view of a portion of an energy absorbing wall assembly, such as shown in  FIG. 1 , further including a permeable fence. 
           [0006]      FIG. 3  shows a cross-sectional side view of a precursor assembly for forming a column and panel fence for an energy absorbing wall assembly, such as shown in  FIGS. 1 and 2 , the precursor assembly including a footing, elongated member and a retaining bracket. 
           [0007]      FIG. 4  shows the precursor assembly of  FIG. 3  further including a panel positioned on the footing. 
           [0008]      FIG. 5  shows the precursor assembly of  FIG. 4  further including a first column face positioned against a side of the panel. 
           [0009]      FIG. 6  shows the precursor assembly of  FIG. 5  further including a second column face positioned against an opposing side of the panel. 
           [0010]      FIG. 7  shows the precursor assembly of  FIG. 6  further including a cross-piece positioned over the column faces and coupled to the elongated member. 
           [0011]      FIG. 8  shows the precursor assembly of  FIG. 7  wherein the cross-piece is coupled to the column faces, and wherein the cross-piece and elongated member are put into tension to form a column. 
           [0012]      FIG. 9  shows the column of  FIG. 8  further including a cap positioned over the column faces and the cross-piece. 
           [0013]      FIG. 10  shows an isometric view of a portion of a first column and panel fence and a second column and panel fence positioned for forming an energy absorbing wall assembly as shown in  FIG. 1 . 
           [0014]      FIG. 11  shows an isometric view of a portion of a first column and panel fence, a second column and panel fence, and a chain-link fence positioned for forming an energy absorbing wall assembly as shown in  FIG. 2 . 
           [0015]      FIG. 12  shows a cross-sectional view of a energy absorbing wall assembly, such as shown in  FIG. 1 , having an energy absorbing filler material including used tires positioned between first and second self-supporting wall structures. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    In some embodiments, as shown in  FIG. 1 , an energy absorbing wall assembly  2  may include a first self-supporting wall structure  4 , a second self-supporting wall structure  6  and an energy absorbing filler material  8  positioned therebetween. The second self-supporting wall structure  6  may be positioned substantially parallel to the first self-supporting wall structure  4  and the filler material  8  positioned therebetween may substantially fill an entire space between the first self-supporting wall structure  4  and the second self-supporting wall structure  6 . 
         [0017]    Each self-supporting wall structure  4 ,  6  may be a free-standing structure. Furthermore, each self-supporting wall structure  4 ,  6  may be formed by a wall structure that may be utilized on its own as a functional wall. For example, each self-supporting wall structure  4 ,  6  may be a column and panel fence, such as described in U.S. patent application Ser. No. 12/631,495, filed on Dec. 4, 2009, by the inventor of the present invention and incorporated herein in its entirety by this reference. As the exterior of the energy absorbing wall assembly  2  may be formed by the self-supporting wall structures  4 ,  6  and free-standing fencing may be utilized as the self-supporting wall structures  4 ,  6 , the energy absorbing wall assembly  2  may be aesthetically pleasing and may, thus, be configured with a selected surface finish pattern, texture, color, etc., to provide an appearance that is consistent with that of the surrounding community. In other words, at least one of the first and second self-supporting wall structures  4 ,  6  may be, or at least have the appearance of, a conventional fence. Furthermore, the first and second self-supporting wall structures  4 ,  6  may provide an anti-spalling and anti-ricochet outer surface of the energy absorbing wall assembly  2 . 
         [0018]    Each self-supporting wall structure  4 ,  6  may comprise preformed concrete panels  10  positioned between and held upright by columns  12  anchored to the ground, such as by a footing  14  ( FIGS. 3-9 ), a foundation, or another type of anchor. In some embodiments, the columns  12  of the first self-supporting wall structure  4  may be aligned with columns  12  of the second self-supporting wall structure  6 , as shown in  FIG. 1 . In additional embodiments, the columns  12  of the first self-supporting wall structure  4  may be staggered relative to the columns  12  of the second self-supporting wall structure  6 , as shown in  FIG. 2 . 
         [0019]    In some embodiments, the first and second self-supporting wall structures  4 ,  6  may be substantially identical in construction and height, such as shown in  FIGS. 1 and 2 . This may allow common components, materials, tools and construction methods to be used for each self-supporting wall structure  4 ,  6 . In additional embodiments, the first and second self-supporting wall structures  4 ,  6  may be significantly different in one or more of construction, height, and other aspects (not shown). For example, the first self-supporting wall structure  4  may comprise an outer wall of a building and the second self-supporting wall structure  6  may be a fence spaced from the outer wall of the building (not shown). In some embodiments, a permeable fence  16  may be positioned between the first and second self-supporting wall structures  4 ,  6 , such as shown in  FIG. 2 . Additionally, the permeable fence  16  may extend higher than the first and second self-supporting wall structures. For example, and as illustrated in  FIG. 2 , a chain-link fence may be positioned between and extend above the first and second self-supporting wall structures  4 ,  6 . Additionally, the permeable fence  16  may be positioned adjacent one of the first and second self-supporting wall structures  4 ,  6 . At least a portion of the energy absorbing filler material  8  may be flowable, at least when initially positioned between the first and second self-supporting wall structures  4 ,  6 , and the flowable, energy absorbing filler material  8  may penetrate the permeable fence  16  and surround and substantially encapsulate the lower portion of the permeable fence  16 . 
         [0020]    The energy absorbing filler material  8  may comprise a material that is initially flowable, to facilitate the positioning of the energy absorbing filler material  8  between the first and second self-supporting wall structures  4 ,  6 . After positioning between the first and second self-supporting wall structures  4 ,  6  the energy absorbing filler material  8  may exhibit energy absorbing properties. In some embodiments, the energy absorbing filler material may be a monolithic structure, such as a monolithic collapsible material comprising a relatively brittle cellular matrix encapsulating relatively small, collapsible pockets, such as gas (e.g., air) pockets. For example, the energy absorbing filler material  8  may be a cellular concrete. In some embodiments a cellular concrete may be formed from hydraulic cement, water and pre-formed foam. In additional embodiments, other methods of entraining gas into uncured concrete may be utilized (e.g., gas producing chemical reactants, aspirating nozzles, porous aggregate, aeration, etc.). In some embodiments, a cellular concrete comprising about 40 percent air to about 60 percent air may be utilized. For a non-limiting example, a cellular concrete comprising about 50 percent air may be utilized. The amount of air entrained in the cellular concrete may be varied according to the application that the energy absorbing wall assembly  2  is intended and the configuration and intensity of any kinetic energy that the energy absorbing wall assembly  2  is configured to absorb. In additional embodiments, the energy absorbing filler material  8  may comprise a flowable particulate, such as one or more of sand, dirt, gravel, and other flowable particulates. The energy absorbing filler material  8  may also comprise additional material and structures. In some embodiments, the energy absorbing filler material  8  may comprise discrete energy absorbing structures positioned between the wall structures that may form cavities and voids that may be filled with the flowable material. For example, used tires  18  ( FIG. 12 ) may be stacked between the first and second self-supporting wall structures  4 ,  6 . In view of this, the energy absorbing filler material  8  may comprise a plurality of discrete energy absorbing structures encapsulated in a monolithic energy absorbing material. 
         [0021]    In some embodiments, an energy absorbing wall assembly  2  may be assembled by first assembling first and second self-supporting wall structures  4 ,  6  spaced apart and then filling the space between the first and second self-supporting wall structures  4 ,  6  with an energy absorbing filler material  8 . For example, the first and second self-supporting wall structures  4 ,  6  may be assembled by first positioning footings  14 , then securing elongated members  20  to the footings  14  and positioning an optional retaining bracket  21  about each elongated member  20 , as shown in  FIG. 3 . Next, end portions of the panels  10  may be positioned over the footings  14  and generally aligned with respective elongated members, as shown in  FIG. 4 . The panels  10  may be held in position by temporary braces (not shown) until the columns  12  are assembled. 
         [0022]    After the panels  10  are positioned, a first column face  22  may be positioned adjacent the end portions of the panels  10 , as shown in  FIG. 5 , and a second column face  24  may be positioned adjacent the ends portions of the panels  10  opposite the first column face  22 , as shown in  FIG. 6 . Optionally, if the first and second column faces  22 ,  24  are joined together by a central portion (i.e., the first and second column faces are a single piece) (not shown) the first and second column faces  22 ,  24  may be positioned simultaneously, such as by lowering the first and second column faces  22 ,  24  over the elongated member  20  and footing  14 . 
         [0023]    The lower ends of the first and second column faces  22 ,  24  may be held against the panels  10  by a retaining bracket  21  or by another structure. If a retaining bracket  21  is used, the retaining bracket  21  may comprise a metal bracket that may be deformed or may be rotated, such as by a hammer, to hold the lower ends of the column faces  22 ,  24  firmly against the panels  10 . A cross-piece  26  may then be positioned at the upper end of the column faces  22 ,  24  and, optionally, a retainer  36  may be positioned over the cross-piece  26 , as shown in  FIG. 7 . A first end  38  of the cross-piece  26  may be coupled to the first column face  22 , a second end  40  of the cross-piece  26  may be coupled to the second column face  24 , and an intermediate portion of the cross-piece  26  may be coupled to the elongated member  20 , as shown in  FIG. 8 . A portion of the cross-piece  26  may then be deformed, such as by rotating the bolt  32 , and the cross-piece  26  and the elongated member  20  may be held in tension by the footing  14 , the first column face  22  and the second column face  24 . The tensioned cross-piece  26  may then hold the column faces  22 ,  24  firmly against the panels  10  and apply a longitudinally oriented compressive force to the column faces  22 ,  24 . Upon putting the cross-piece  26  and the elongated member  20  into tension, the column  12  may support the panels  10  and any temporary braces (not shown) may then be removed. Finally, the cap  28  may be positioned over the upper end of the column  12 , as shown in  FIG. 9 . 
         [0024]    In some embodiments, the first and second self-supporting wall structures  4 ,  6  may be comprised of preformed concrete components. The panels  10  may be cast from concrete in a single monolithic piece or as a plurality of pieces assembled together to form the panel. For example, each panel  10  and each may be formed of two monolithic sheets, each sheet cast in a mold, and a face of each sheet may have a finished surface imparted by the mold. The sheets may be assembled back to back, such the faces of the sheets, having the finished surface imparted by the mold, may form the outer surface of the panel  10 . Optionally, each panel  10  may also include reinforcing structures, such as one or more of reinforcing bar (rebar), reinforcing fiber (e.g., glass fiber, steel fiber, synthetic fiber, natural fiber, polypropylene fiber, cellulose fiber, asbestos fiber, carbon fiber, etc.), and reinforcing wire therein and may include materials, such as adhesives and filler material, therebetween. Additionally, each panel  10  may include a hollow cavity therein. As the concrete panels  10  may be lightweight (e.g., hollow, lightweight aggregate, etc.) and may be fiber reinforced, the panels  10  may prevent or reduce spalling and ricochet that may otherwise result from an impact, such as by a projectile, into a conventional concrete structure. 
         [0025]    Additionally, with reference to  FIG. 9 , the column faces  22 ,  24  may be comprised of concrete and may similarly be preformed, such as in a mold. For example, each of the column faces  22 ,  24  may be formed of cast concrete, which may be reinforced, such as with one or more of reinforcing bar (rebar), reinforcing fiber (e.g., glass fiber, steel fiber, synthetic fiber, natural fiber, polypropylene fiber, cellulose fiber, asbestos fiber, carbon fiber, etc.) and reinforcing wire. In some embodiments, each of the column faces  22 ,  24  may not include any exterior or exposed portions that are not formed of concrete. Each column face  22 ,  24  may be cast from concrete in a single monolithic piece or as a plurality of pieces assembled together to form each column face  22 ,  24 , similarly to the panels  10 . Optionally, each column face  22 ,  24  may also include reinforcing structures, such as one or more of reinforcing bar (rebar), reinforcing fiber, and reinforcing wire therein and may include materials, such as adhesives and filler material, therebetween. Additionally, each column face  22 ,  24  may include a hollow cavity therein. As the concrete column faces  22 ,  24  may be lightweight (e.g., hollow, lightweight aggregate, etc.) and may be fiber reinforced (e.g., glass fiber, steel fiber, synthetic fiber, natural fiber, polypropylene fiber, cellulose fiber, asbestos fiber, carbon fiber, etc.), the column faces  22 ,  24  may prevent or reduce spalling and ricochet that may otherwise result from an impact, such as by a projectile, into a conventional concrete structure. 
         [0026]    Although certain concrete panels and concrete column faces have been described, panels and column faces formed of other materials and by other methods may also be used, as will be understood by a person of ordinary skill in the art. 
         [0027]    In addition to assembling the first and second self-supporting wall structures  4 ,  6 , a permeable fence  16 , such as a chain-link fence, may be assembled at a position between the first and second self-supporting wall structures  4 ,  6 , as shown in  FIG. 2 . The permeable fence  16  may be substantially taller than the first and second self-supporting wall structures  4 ,  6  and may be positioned relatively close to one of the first and second self-supporting wall structures  4 ,  6 , such as within a few inches. The permeable fence  16  may be a conventional fence, such as a chain-link fence, and may be assembled according to conventional methods, such as by securing fence posts in concrete footings and attaching a chain-link fencing to the fence posts. Optionally, barbed wire, razor wire or another climbing deterrent  42  may be attached at or near the top of the permeable fence  16 . Additionally, the portion of the permeable fence  16  that is encapsulated within the energy absorbing filler material  8  may facilitate the distribution of energy loads through the energy absorbing wall assembly  2 . For example, a relatively large amount of kinetic energy, such as from a vehicle impact, may be exerted on a relatively small region of the energy absorbing wall assembly  2 , such as upon a single panel  10 . The permeable fence  16  may distribute the kinetic energy from the impact among adjacent portions of the energy absorbing wall assembly  2 , which may facilitate an efficient absorption of the kinetic energy by the energy absorbing wall assembly  2  and may also prevent a breach of the energy absorbing wall assembly  2 . 
         [0028]    After the first and second self-supporting wall structures  4 ,  6  are installed, as shown in  FIG. 10 , and optionally, the intermediate permeable fence  16 , as shown in  FIG. 11 , the energy absorbing filler material  8  may be positioned between the first and second self-supporting wall structures  4 ,  6 . If any discrete energy absorbing structures, such as used tires  18 , are utilized, they may be positioned between the first and second self-supporting wall structures  4 ,  6 , in a series of laterally adjacent vertical stacks, as shown in  FIG. 12 . Optionally, a first self-supporting wall structure  4  may be assembled, structural material, such as used tires  18 , may be stacked one on top of the other, the individual tires oriented horizontally, adjacent the first self-supporting wall structure  4 , then the second self-supporting wall structure  6  may be assembled. Finally, a flowable energy absorbing filler material  8  may be directed between the first and second self-supporting wall structures  4 ,  6  and may substantially fill the remaining space therebetween. 
         [0029]    If the first and second self-supporting wall structures  4 ,  6  include any permeable regions where flowable energy absorbing filler material  8  may flow through, the permeable regions may be sealed to prevent flow of the flowable energy absorbing filler material  8  therethrough. 
         [0030]    In some embodiments, an uncured cellular concrete may be flowed between the first and second wall structures  4 ,  6 , such as by a concrete pump. After the cellular concrete is flowed into the space between the first and second self-supporting wall structures  4 ,  6  the cellular concrete may become cured and provide a monolithic, rigid, cellular structure. 
         [0031]    In additional embodiments, a flowable particulate may be directed into the space between the first and second self-supporting wall structures  4 ,  6 . For example, a flowable particulate comprising one or more of sand, dirt, gravel, and other flowable particulates may be directed into the space between the first and second self-supporting wall structures  4 ,  6 . 
         [0032]    If structural features are positioned between the first and second self-supporting wall structures (e.g., a permeable fence  16 , used tires  18 , etc.) the flowable energy absorbing filler material  8  (e.g., uncured cellular concrete, flowable particulate, etc.) may be flowed around and optionally through such structural features. 
         [0033]    In some embodiments, the energy absorbing wall assembly  2  may be repaired after one or more energy absorption events. After one or more energy absorption events, such as impact with one or more projectiles, the affected regions of the first and second self-supporting wall assemblies  4 ,  6  may be removed. For example, columns  12  in the affected regions may be disassembled, and affected (i.e., damaged) columns  12  and panels  10  may be removed. After removal of the affected columns  12  and panels  10  the underlying energy absorbing filler material  8  may be repaired. In some embodiments, a portion of damaged cellular concrete may be removed to form a cavity in a monolithic energy absorbing filler material  8  and the cavity may be filled with uncured cellular concrete, which may then cure within the cavity. New columns  12  and panels  10  may then be installed to replace the previously removed affected columns  12  and panels  10 . In additional embodiments, a cavity may be formed and one or more flow paths extending from the cavity to an upper surface may be formed in the monolithic energy absorbing filler material  8  while the columns  12  and panels  10  are removed. Then cellular concrete may be flowed into the cavity through the one or more flow paths after the new columns  12  and panels  10  have been installed. Such methods may allow a time efficient and cost effective method of repair to the energy absorbing wall assembly  2  after one or more energy absorption events. For example, an energy absorbing wall assembly  2  may be installed at a site where repeated kinetic energy events may be expected, such as a shooting range or testing facility, and the energy absorbing wall assembly  2  may be regularly and repeatedly repaired. 
         [0034]    The energy absorbing wall assemblies  2  described herein may readily absorb energy, such as from impacts of vehicles or projectiles, from shock waves, such as those resulting from explosives or industrial accidents (e.g., at chemical plants, refineries), or from other kinetic energy sources. In view of this, the energy absorbing wall assemblies  2  described herein may be utilized in a number of applications where energy absorption may be beneficial. In some embodiments, an energy absorbing wall assembly  2  may be utilized as a security wall. As a security wall an energy absorbing wall assembly  2  may provide protection by providing a barrier that may be difficult to penetrate or climb over. The energy absorbing wall assembly  2  may absorb a shock wave and resulting shrapnel directed toward the wall from an explosive detonating near the energy absorbing wall assembly  2 . Additionally, the energy absorbing wall assembly  2  may absorb the impact of a vehicle intentionally rammed into the energy absorbing wall assembly  2 , may absorb the energy of projectiles, such as bullets, and otherwise prevent penetration of the energy absorbing wall assembly  2  by potentially harmful kinetic energy into a protected area behind the energy absorbing wall assembly  2 . In additional embodiments, energy absorbing wall assemblies  2  may be utilized in other applications, such as near roadways to absorb the impact of an automobile veering off of the roadway, or as an exterior wall of a building among other possible applications. 
         [0035]    While the present invention has been described herein with respect to certain embodiments, those of ordinary skill in the art will recognize and appreciate that it is not so limited. Rather, many additions, deletions and modifications to the embodiments described herein may be made without departing from the scope of the invention as hereinafter claimed. In addition, features from one embodiment may be combined with features of another embodiment while still being encompassed within the scope of the invention as contemplated by the inventor.