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CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application claims the benefit of U.S. provisional patent application Ser. No. 61/068,274 filed on Mar. 6, 2008. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present application is directed to a new design of architectural concrete structure and to a wall system formed by a plurality of such structures. Concrete blocks are used extensively in building construction in a wide variety of designs. Prior art blocks and block systems for forming walls include the following U.S. Pat. Nos. 2,647,392; 2,701,464; 4,018,018; 4,075,808; 4,514,949; 4,854,097; 6,032,424; and 6,223,491. 
         [0003]    Concrete blocks are heavy to handle and do not provide good insulating characteristics. U.S. Pat. No. 4,854,097 discloses a building block having improved insulating characteristics in which at least a part of the volume within the concrete is filled with highly insulating foam. 
         [0004]    It is an object of the present invention to provide a an architectural concrete structure and a system for forming walls or other structures in which the components have good insulating characteristics and has a large central, open passageway to provide a structure having lower weight than would be expected for the size of the component formed and having good insulating characteristics. 
         [0005]    Other objects and advantages of the present invention will become apparent to those skilled in the art upon a review of the following detailed description of the preferred embodiments and the accompanying drawings. 
       SUMMARY OF THE INVENTION 
       [0006]    The invention is directed to an architectural concrete structure and a wall system formed with a plurality of architectural concrete structure wherein each block has first and second cement sections spaced apart and joined together with steel reinforcing bars and tubular members filled with cement. The first and second sections have parallel outer wall surfaces and inner wall surfaces which taper outwardly in an upward direction. Foam insulation is secured to each of the tapering wall surfaces, which insulation members define a tapered passageway extending through the length of the structure. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is a perspective view showing two architectural concrete structures of the present invention with the upper structure resting upon the lower structure. 
           [0008]      FIG. 2  is a side elevational view partially in section. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0009]    Referring to the drawings there is shown in  FIG. 1  two architectural concrete structures  10  of the present invention including an upper structure stacked upon a lower structure  10 . The structure  10  extends along a longitudinal path from a first end  34  to a second end  36  and includes a first section  12  of poured Portland cement or concrete and a second section  14  of Portland cement or concrete. The first section  12  and second section  14  are spaced apart from one another and each has an upper surface  16  and a lower surface  18  extending between the first end  34  and second end  36 . The first section  12  includes a flat outer wall surface  20  extending longitudinally along a path parallel to axis A from the first end  34  to the second end  36  and extending in height from the lower surface  18  to the upper surface  16 . The second section  14  has an outer wall surface  20  which also extends from the first end  34  to the second end  36  and in height from the lower surface  18  to the upper surface  16 . Axis A defines the central longitudinal axis of the concrete  10 . The outer wall surfaces  20  are parallel to each other. 
         [0010]    As can be seen in  FIG. 1 , the first section  12  and the second section  14  each has an inner wall surface  22 , each of which is disposed at an angle flaring away from one another as they extend upwardly from the lower surface  18  toward the upper surface  16 . The included angle between the respective inner wall surfaces  22  and the lower surface  18  is approximately 75°±10°. Such inner wall surfaces  22  extend between the first end  34  and second end  36  of their respective first section  12  and second section  14 . Preferably the respective inner wall surfaces  22  extend upwardly from their respective lower surfaces  18 , flaring outwardly away from each other but do not extend completely to the respective upper surfaces  16 . 
         [0011]    Positioned in interfacial contact with each of the inner wall surfaces  22  is a flat sheet of rigid foam material for providing insulation for the block  10 . The first flat insulation member  28  and the second flat insulation member  30  each extends upwardly from the lower surfaces  18  of their respective first section  12  and second section  14  to an upper edge  51  slightly below the respective upper surfaces  16  at the termination of their respective adjacent inner wall surfaces  22 . With this construction, there is provided a ledge  40  of cement or concrete between the top edges  51  of each of the first flat insulation member  28  and second flat insulation member  30 . The presence of the respective ledges  40  assists in retaining the first and second flat insulation members  28  and  30  snuggly against their respective inner wall surfaces  22  and prevents direct contact against such upper edges  51  of the first and second flat insulation members  28  and  30  by the structure  10  positioned above it, as shown in  FIG. 1 . 
         [0012]    The foam material could be one of a number of well known plastics but preferably is one having an R-value in the range of R5.6 to R8 per inch of thickness such as polyisocyanurate or polyurethane, for example. Foam polystyrene could also be used for those situations in which a lower R-value is acceptable. 
         [0013]    As can be seen in  FIG. 1 , the first and second flat insulation members  28 ,  30  define an open passageway  32  which is wider in the area adjacent the upper surface  16  than in the area adjacent the lower surface  18 . The passageway  32  extends from the first end  34  to the second end  36 . 
         [0014]    A pair of ⅜ inch reinforcing bars  38  extends across the passageway  32  and through apertures  42  in the respective first and second flat insulation members  28 ,  30  slightly below the ledges  40 . The reinforcing bars  38  extend into the cement or concrete of the respective first and second sections  12 ,  14  and have down turned elbows  45  for secure engagement to such sections  12 ,  14 . 
         [0015]    Also, spanning the passageway  32  in an area approximately midway between the upper surfaces  16  and lower surfaces  18  is a length of polyvinylchloride (PVC) pipe  44  having a diameter (for example about 3″) sufficiently large to receive therein cement as it is being introduced into a mold for forming the block  10 . The PVC pipe  44  extends through apertures  46  in the respective first and second flat insulation members  28 ,  30  and extends a short distance into each of the respective first and second sections  12 ,  14 . The reinforcing bars  38  and the PVC pipe  40  are positioned in the respective apertures  42  and  46  of the first and second flat insulation members prior to pouring cement or concrete in the mold used for forming the architectural concrete structure  10 . Upon pouring the cement into the mold cavity, the elbows  45  of the reinforcing bar  38  will be encased by the cement and the open ends of the PVC pipe  44  will receive cement sufficiently to completely fill the PVC pipe  44  as shown in the breakaway section of the pipe in  FIG. 1 . 
         [0016]    As will be appreciated, in addition to providing reinforcing, the reinforcing bars  38  maybe used for gripping and lifting the blocks  10 . 
         [0017]    There is also provided reinforcing mesh  48  and wires for supporting the mesh during the step of pouring concrete in the mold as shown in  FIG. 2 . For example, the reinforcing mesh  48  could be 18 gauge wire and spaced apart 6″ vertically and horizontally. 
         [0018]    If desired, the first section  12  could be poured with concrete of one color and the second section  14  could be poured with a different color thereby permitting a decorative pattern to be formed when constructing a wall simply by having some blocks  10  laid with the first section  12  facing outwardly and other blocks  10  laid with the second section  14  facing outwardly. In addition, various designs or architectural features can be molded or formed on the first section  12  and second section  14 . Also grout or mortar can be positioned in the joint between adjacent structures to peal the interface and to provide for a fluid tight use between the structures. 
         [0019]    The above detailed description of the present invention is given for explanatory purposes. It will be apparent to those skilled in the art that numerous changes and modifications can be made without departing from the scope of the invention. Accordingly, the whole of the foregoing description is to be construed in an illustrative and not a limitative sense, the scope of the invention being defined solely by the appended claims.

Summary:
An architectural concrete structure and a wall system formed with a plurality of architectural concrete structure wherein each block has first and second cement sections spaced apart and joined together with steel reinforcing bars and tubular members filled with cement. The first and second sections have parallel outer wall surfaces and inner wall surfaces which taper outwardly in an upward direction. Foam insulation is secured to each of the tapering wall surfaces, which insulation members define a tapered passageway extending through the length of the structure.