Patent Abstract:
A structural wall section having a sandwich like structure, which includes an external vertical panel and an internal vertical panel spaced apart in a parallel relationship, further including of a vertical insulating layer. Between the panels there is a space, “core” which includes a vertical layer of concrete, the layer of concrete contains vertical steel reinforcements, a support structure for the internal panel, and a rigid spacer wherein said spacer is positioned horizontally between the external panel and the support structure of the internal panel. The outer surface of the external panel is covered with a coating layer.

Full Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to the field of insulated walls for building, more particularly, to insulated load bearing walls and the construction thereof.  
       BACKGROUND OF THE INVENTION  
       [0002]     The field of wall structure elements has provided many building solutions in the form of various sandwiched wall structures. The main parameters to consider in the construction of such a wall are: 1) load capacity, 2) insulation, 3) thickness, 4) cost, and 5) complexity to build. For example U.S. Pat. No. 4,998,394 provides such a wall structure which claims to provide solutions for the above-mentioned parameters. However, the load capacity of the wall disclosed in said patent is insufficient for the construction of high rise building. Furthermore, the need for additional insulation layers, creates a relatively thick wall. U.S. Pat. No. 5,845,445 describes an insulated concrete from which also has insufficient load bearing capacity and relatively poor insulating capabilities. There are many types of such wall structures; however all have at least one insufficiency with respect to the parameters mentioned above.  
         [0003]     In 1914 in Sweden the foamed concrete was invented by adding aluminum powder to cement, lime, water, and silica sand, which caused the mixture to expand dramatically. The Swedes allowed this “foamed” concrete to harden in a mold, and then they cured it in a pressurized steam chamber-an autoclave to create autoclaved aerated concrete (AAC, also called autoclaved cellular concrete—ACC). At a density of roughly one-fifth that of conventional concrete and a compressive strength of about one-tenth, AAC is used in load-bearing walls only in low-rise buildings. The material is also fairly friable and must be protected from weather with siding or coating. On the positive side, it insulates much better than concrete and has very good sound absorbing characteristics.  
         [0004]     Accordingly, there is a long felt need for a wall structure with improved load bearing capability, good insulation properties, minimal thickness, low cost and simple to assemble.  
         [0005]     It is therefore an objective of the present invention to provide a wall structure which provides the above-mentioned properties.  
         [0006]     It is yet a further objective of the present invention to provide a method for constructing such a wall.  
         [0007]     Other objectives of the invention shall become apparent as the description proceeds.  
       SUMMARY OF THE INVENTION  
       [0008]     The present invention provides a structural wall section having a sandwich like structure comprising an external vertical panel and an internal vertical panel spaced apart in parallel relationship, further comprising of a vertical insulating layer wherein between said panels there is a space, “core” comprising 
    a vertical layer of concrete wherein said concrete layer contains vertical steel reinforcements, a support structure for the internal panel,     and a rigid spacer wherein said spacer is positioned horizontally between the external panel and the support structure of the internal panel,     wherein the outer surface of the external panel is covered with a coating layer.    
 
         [0012]     Optionally, the wall comprises horizontal tie elements which secure the outer coating of the external panel to the core.  
         [0013]     Further optionally, the wall structure comprises strips which connect between sections of the wall and pegs which reinforce the wall structure to the ceiling and/or floor. Further provided by the present invention, is a method for forming a wall structure comprising of the following steps, which may be carried out in various sequences wherein the casting of the concrete must always be the final step. 
    a) positioning the external panel,     b) constructing and positioning the support structure on which the internal panel is supported, wherein said structure is constructed at a given distance and parallel to the external panel such that there is a hollow space between the external panel and the internal panel,     c) vertically positioning a steel reinforcement in the hollow space between the external panel and support structure of said internal panel,     d) installing the rigid spacers,     e) covering the outside surface of the external panel with a coating layer,     f) positioning a vertical insulation layer within the core     g) mounting the internal panel on the support structure,     h) casting concrete into the hollow space between the external panel and internal Panel.    
 
         [0022]     Optionally, wherein horizontal tie elements are employed for securing the coating layer to the core, said tie elements are installed in the process of applying said coating.  
     
    
     BRIEF DESCRIPTIONS OF THE DRAWING  
       [0023]      FIG. 1  is a cross sectional view of the wall structure.  
         [0024]      FIG. 2  is a sectional view of the wall structure.  
         [0025]      FIG. 3  is a top plan view of a corner of the wall structure.  
         [0026]      FIG. 4  is a sectional view of the wall structure. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0027]     The following description is illustrative of embodiments of the invention. The following description is not to be construed as limiting, it being understood that the skilled person may carry out many obvious variations to the invention.  
         [0028]     The present invention provides a load bearing wall structure which is constructed in a layered manner wherein insulating and reinforcing elements are sandwiched between an external coated panel and an internal panel.  
         [0029]     In accordance with a particular embodiment of the invention, with reference to FIGS.  1  to  4 , there is provided a wall structure comprising;  
         [0030]     An outside coating layer ( 1 ). Said layer protects the external panel ( 2 ) from mechanical damage and may further provide insulation against permeation of water and humidity. The primary functions of the outside surface are decorative, protection and insulation. Any material which may impart said functions is suitable for use as the outside coating layer. Non-limiting examples of suitable coating materials include stone, marble, mortar, wood, aluminum, glass, porcelain and ceramics.  
         [0031]     The external panel ( 2 ) can be constructed of various types of materials which are suitable for bearing the coating layer and functioning as a concrete forming panel. Non-limiting examples of suitable materials for the external panel include gypsum board, rock sheet, wood panels and the like. According to a preferred embodiment of the invention, the external panel is constructed of building blocks. Non-limiting examples of suitable blocks include concrete and AAC, e.g. Ytong® building blocks. More preferablyan AAC block. Thus, providing improved thermal and sound insulation. The external panel ( 2 ) may be constructed of blocks of various sizes depending on the technical requirements of the structure.  
         [0032]     According to an embodiment of the invention wherein the external panel is not constructed of blocks, there may be a need to insert a vertical layer of insulating material within the core. Non-limiting examples of suitable insulating materials include polymeric materials such as foaming polystyrene.  
         [0033]     The internal panel ( 3 ) is supported on a support structure ( 4 ). Non-limiting examples of suitable materials for said internal panel include rock sheet, gypsum board, wood panel and polymeric materials. The support structure ( 4 ) and internal panel ( 3 ) are positioned parallel to the external panel ( 2 ) and at a distance such that a hollow space is formed between the internal panel ( 3 ) and external panel ( 2 ) into which the concrete is cast ( 8 ). The distance between the internal panel ( 3 ) and external panel ( 2 ) is adjusted according to the structural requirements. The support structure ( 4 ) is preferably constructed of horizontal and vertical beams. Non-limiting examples of suitable materials for said support structure include steel, aluminum or wood, preferably steel.  
         [0034]     The steel reinforcement ( 5 ) can be of various forms suitable for providing structural strength to the wall structure. Preferably, the steel reinforcement ( 5 ) is a network of steel rods interweaved. Said network is positioned at a fixed distance, parallel to the external panel ( 2 ) and within the hollow space in the core of the wall. The fixed distance between the steel reinforcement ( 5 ) and the external panel ( 2 ) is maintained by rigid spacers ( 6 ), which are positioned horizontally between said external panel ( 2 ) and the steel reinforcement ( 5 ). The length of the spacers ( 6 ) is adjusted to the required distance between the external panel ( 2 ) and steel reinforcement ( 5 ). Said spacer ( 6 ) can be made of metal, wood, plastic or any suitable material for this purpose. According to yet a further embodiment of the invention the steel reinforcement may be in the form of steel beams positioned vertically within the core and optionally connected by other steel connectors.  
         [0035]     According to a further embodiment of the invention, the tie elements ( 7 ) which are preferably made of steel, are connected at one end to the outside coating layer ( 1 ) and at the other end to the internal panel ( 3 ) and/or support structure ( 4 ). The function of said tie elements ( 7 ) are to secure the outside coating layer ( 1 ) to the core of the wall structure.  
         [0036]     Various types of concrete ( 8 ) may be used for casting into the hollow space, as may be appreciated by the skilled artisan. Preferably, the characteristics of the concrete are such that it is free flowing, self leveling, rapid hardening with negligible retardation, improved anti-segregation properties and excellent workability. Such concrete is also known in the art as Self Compacting Concrete (SCC). Said properties are important for ensuring that the concrete when cast, flows freely to fill all of the hollow space such that there are no voids where the concrete did not settle in. Furthermore, said properties are important for providing a wall structure of the required technical features, e.g. strength.  
         [0037]     According to a further preferred embodiment of the invention, the wall structure may be constructed to include an opening e.g., window or door, by creating the required size opening in the external panel, support structure and internal panel and then building a frame on the internal perimeter of the opening. Thus, when the concrete is cast to the hollow space it will not seep through the opening. Said frame may further function as door post or mounting frame on which the door or window is mounted.  
         [0038]     According to a specific embodiment of the invention, with reference to  FIG. 2 , the wall structure further comprises a strip ( 9 ) which connects between sections of the external panel. Said strip ( 9 ) provides reinforcement to the wall structure and provides improved insulation. Said strip ( 9 ) is preferably of rigid material. Non-limiting examples of suitable materials for the strip are cement board, gypsum board and the like.  
         [0039]     According to yet a further embodiment of the invention with reference to  FIG. 4 , the wall structure comprises a peg ( 10 ) which reinforces the floor and/or ceiling of the building to the wall. Said peg ( 10 ) is embedded in the ceiling/floor and connects to the wall structure. The peg ( 10 ) may connect to any part of the wall structure, e.g. to the concrete ( 8 ) or preferably into the external panel ( 2 ). The peg ( 10 ) may be of any suitable material, e.g. steel, wood, preferably steel.  
         [0040]     Optionally, the wall structure further comprises insulating material ( FIG. 4 ;( 11 ),( 14 )) in the seam between the ceiling/floor and the wall structure. Thus, providing improved insulation. Non-limiting examples of insulating materials are polystyrene and polyurethane.  
         [0041]     The side of the ceiling/floor which faces the outer side of the structure may be coated with an external coating ( FIG. 4 ;( 12 )).  
         [0042]     According to an optional embodiment of the invention, the seam between the ceiling and the internal panel of the wall structure is hidden by a decorative molding ( 13 ). The seam between the floor and the wall structure is hidden by the floor sub-base ( 15 ) on which the flooring finish ( 16 ) is mounted.  
         [0043]     The overall thickness of the complete wall structure is dependent upon the dimensions of the elements of the wall and the distances between them, all of which may be adjusted to the functional and structural requirements. The thickness of the wall structure is preferably between 10 cm to 50 cm. As may be appreciated by the skilled artisan, at certain wall thicknesses reinforcements may be required.  
         [0044]     In accordance with a particular aspect of the invention, with reference to  FIGS. 1-4 , there is provided a method for constructing wall structures comprising of the following steps; 
    a) positioning the external panel ( 1 ),     b) constructing and positioning the support structure ( 4 ) on which the internal panel ( 3 ) is supported, wherein said structure is constructed at a given distance and parallel to the external panel ( 2 ) such that there is a hollow space ( 8 ) between the external panel ( 2 ) and the internal panel ( 3 ),     c) vertically positioning a steel reinforcement ( 5 ) in the hollow space between the external panel ( 2 ) and support structure ( 4 ) of said internal panel,     d) installing the rigid spacers ( 6 ),     e) covering the outside surface of the external panel ( 2 ) with a coating layer ( 1 ),     f) mounting the internal panel ( 3 ) on the support structure,     g) casting concrete into the hollow space ( 8 ) between the external panel ( 2 ) and internal Panel ( 3 ).    
 
         [0052]     Optionally, wherein horizontal tie elements ( 7 ) are employed for securing the coating layer ( 1 ) to the core, said tie elements ( 7 ) are installed in the process of applying said coating.  
         [0053]     According to a preferred embodiment of the invention the external panel ( 2 ) is constructed of building blocks, preferably of AAC blocks. Thus, the function of the vertical insulation layer is imparted onto the AAC blocks which display improved insulating properties. Accordingly, the need for a separate insulating layer is obviated. According to the present embodiment the external panel provides all three functions of a concrete forming panel, bearing the outer coating layer and insulation.  
         [0054]     Optionally, wiring, plumbing and other building elements may be installed in the wall before the final installation of the internal panel ( 3 ) and the casting of the concrete ( 8 ).  
         [0055]     Optionally, upon completing the casting of the concrete and subsequent drying thereof, the inside surface of the internal panel ( 3 ) is coated with a coating such as paint, wall paper or any suitable finish.  
         [0056]     According to a specific embodiment of the method of the present invention, with reference to  FIG. 2 , a strip ( 9 ) which connects between sections of the external panel is inserted into the external panel ( 2 ) in a longitudel orientation, hence, providing insulation and rigidness to the seams of the wall structure. The strip ( 9 ) is installed by making a cut along the outer profile of the external panel of the wall sections, which are to be connected, and then sliding the strip into the cut. Non-limiting examples of suitable materials for the strip are cement board, gypsum board and the like.  
         [0057]     According to yet a further embodiment of the method of the present invention with reference to  FIG. 4 , the wall structure is reinforced to the floor and/or ceiling of the building by a peg ( 10 ) which is embedded in the ceiling/floor and connects to the wall structure. The peg ( 10 ) may be inserted such that it connects to any part of the wall structure, e.g. to the concrete ( 8 ) or preferably into the external panel ( 2 ). The peg ( 10 ) may be of any suitable material, e.g. steel, wood, preferably steel.  
         [0058]     Optionally, insulating material ( FIG. 4 ; ( 11 ), ( 14 ) may be applied to the seams between the ceiling/floor and the wall structure. Thus, providing improved insulation. Non-limiting examples of insulating materials are polystyrene and polyurethane.  
         [0059]     While the steps of the present method have been described in a particular order, it is within the scope of the present invention to alter the order of the construction steps. Further more, certain steps may be carried but at various locations, and not necessarily at the construction site. For example the coating layer of the external panel may be applied prior to transferring the external panel to the construction site.  
         [0060]     The present wall structure and method for the construction thereof are advantageous in that they provide a wall with load bearing capability, improved insulation and at a relatively minimal wall thickness. The use of AAC blocks of improved insulation compared to conventional concrete blocks obviates the need for further insulation layers in the wall, hence maintaining minimal wall thickness. Furthermore, the incorporation of the reinforcement in the concrete core imparts load bearing capabilities to the wall, thus rendering the wall suitable for the construction of high rise building as well. The use of gypsum board for the inside surface provides for easier and faster finishing and further obviates the need for plastering the walls as in conventional building. The present wall structure and method of construction facilitate the incorporation of pre-fabricated building elements into the construction process. The flexibility in the construction steps provides a building process which is faster than conventional methods and has less rate determining steps which may impede the process.  
         [0061]     While embodiments of the invention have been described by way of illustration, it will be apparent that the invention may be carried out with many modifications, variations and adaptations, without departing from its spirit or exceeding the scope of the claims.  
         [0062]     It should be understood that some modification, alteration and substitution is anticipated and expected from those skilled in the art without departing from the teachings of the invention. Accordingly, it is appropriate that the following claims be construed broadly and in a manner consistent with the scope and spirit of the invention.

Technology Classification (CPC): 4