Abstract:
A lightweight poured-in-place concrete builiding component and method of construction in which a plurality of spaced apart structural members with outer regions and a retaining layer system create a segmented form into which a lightweight concrete slurry is poured. The retaining layer system includes a lath which extends across the structural members on at least one outer region of the structual members. The lath is configured to simultaneously support a significant amount of the lightweight concrete slurry within a segmented form and allow a small amount to exude through the lath, thereby reinforcing a concrete component once cured. Alternative embodiments include the introduction of a barrier between a significant portion of a lath and concrete slurry to, at least reduce the amount on concrete which exudes-through the lath. Other altnerative embodiments include the introduction of insulative materials to the concrete slurry to enhance the insulative qualitites of a concrete component.

Description:
TECHNICAL FIELD  
       [0001]     This invention relates generally to lightweight concrete used in the construction of buildings and other structures. More particularly, it relates to poured-in-place lightweight concrete walls and horizontal components for use as a floor, ceiling or roof of a building or other structure. Lightweight concrete walls, floors, ceilings or roofs formed in such a manner are easy to construct, build out and finish and when cured, are resistant to impact loads.  
       BACKGROUND ART  
       [0002]     In general, concrete has been used to construct walls and horizontal components such as floors, ceilings and flat roofs. However the construction of each type of slab presents a number of challenges. With respect to wall and floor slabs, the adjacent earth must be stabilized and prepared to receive and hold the concrete slurry to be poured. Without proper stabilization of the adjacent earth, a cured wall or floor slab may shift or crack. Preparation may include trenching and leveling the adjacent earth before pouring. Forms made of wood or steel are used to retain the concrete slurry and are removed after curing. Depending of the function of the concrete wall or floor slab, reinforcing bars are cut, wired together and positioned inside the form in such a manner as to add internal strength to the surrounding concrete slurry once cured.  
         [0003]     Building construction that requires walls, floors, ceilings or roofs is typically carried out through the use of prefabricated modular concrete components or slabs. Such prefabricated modular slabs are typically poured, cured and stored offsite until required at the construction site. Typical prefabricated modular slabs are heavy and pose unique challenges in lifting to the final position at the construction site. An alternative is to pour in place. Similar to pouring a slab on the ground, a form must be constructed to hold a concrete slurry in place until cured. Furthermore, a comprehensive network of supports must be constructed to elevate and support the form and concrete slurry until cured. Thereafter the forms and supports are disassembled and removed from the construction site.  
         [0004]     If insulation is required, the construction process includes the addition of insulative materials in the form of fiberglass batts, blown-in insulation, or the use of foam (sprayed or in board form). If conduits or utility ways are required, then the forming of conduits within the form is required before the concrete slurry is cured. This requires the architect, engineer, and/or builder to plan ahead. As can be appreciated, additions after-the-fact require cutting the concrete or making workarounds, both of which are very expensive.  
         [0005]     In view of the above described deficiencies associated with concrete walls and horizontal components, the present invention has been developed to alleviate these drawbacks and provide further benefits to the user. These enhancements are benefits are described in greater detail hereinbelow with respect to several alternative embodiments of the present invention.  
       SUMMARY OF THE INVENTION  
       [0006]     This invention includes features and components that have been invented and selected for their combined benefits and superior performance as poured-in-place lightweight concrete walls and horizontal components. Each of the individual components work in association with the others and are optimally mated for superior performance.  
         [0007]     Referring now to specific embodiments of the lightweight concrete construction components and several of its applications in the building construction business, additional benefits and advantageous features will be appreciated. One embodiment of the present invention is the formation of a slab (horizontal and/or vertical) between adjacent support members, like studs or joists. The support members are preferably metal and secured to a stem wall or other suitable load bearing structure. A retaining layer system, in the form of a metal lath and barrier is applied to the outer regions of the structural members. Extending the retaining larger system access the outer region of the structural members completes a space into which a lightweight concrete slurry may be poured and thereafter allowed to cure to provide a strong, thermally insulating filler that has the ability to withstand severe impact, up to and including forces generated by storms or even high heeled foot traffic. In another embodiment, only one outer region of the structural members are covered by a retaining layer system. The remaining outer regions of the structural members are spanned by a removable forum, thereby completing a space into which a lightweight concrete slurry may be poured. In yet another embodiment, particular to horizontal components, a retaining larger system is fixed across a lower outer region of adjacent structural members to form space into which a lightweight concrete slurry may be poured.  
         [0008]     In another embodiment, a layer of insulative material is fixed within said lightweight concrete slurry. While described here as a retaining layer system between a pair of structural members, the metal lath and/or the barrier may extend over both sides of a plurality of structural members so as to form an extended retaining layer system support. When the lightweight concrete cures, the exposed face of the retaining layer system or metal lath may be finished with a veneer such as stucco to give the surface an attractive finish. Any forms are removed, and the surface may be finished with a covering.  
         [0009]     Among those benefits and improvements that have been disclosed, other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]     The invention will now be described in greater detail in the following way of example only and with reference to the attached drawings, in which:  
         [0011]      FIG. 1  is a cross sectional view showing a structure with poured-in-place lightweight concrete walls and horizontal components.  
         [0012]      FIG. 2  is a cross sectional view of a floor slab showing a retaining layer system for concrete poured as a slurry between adjacent joists.  
         [0013]      FIG. 3  is a cross sectional view of a ceiling slab showing a retaining layer system for concrete poured as a slurry between adjacent joists.  
         [0014]      FIG. 4  is a perspective view of a floor slab showing a retaining layer system for concrete poured as a slurry between adjacent joists.  
         [0015]      FIG. 5  is a cross sectional view of a horizontal slab with an insulative material positioned between layers of a lightweight concrete slurry.  
         [0016]      FIG. 6  is a cross sectional view of a horizontal slab with a barrier that covers joists and lath.  
         [0017]      FIG. 7  is a perspective view of a horizontal slab with joists, a reinforcing member and a utility conduit.  
         [0018]      FIG. 8  is a cross sectional view of a wall depicting a retaining layer system for concrete poured as a slurry between adjacent studs.  
         [0019]      FIG. 9  is a perspective view of a wall depicting a retaining layer system for concrete poured as a slurry between adjacent studs.  
         [0020]      FIG. 10  is a perspective view of a wall depicting another embodiment of a retaining layer system for concrete poured as a slurry between adjacent studs. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0021]     As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale, some features may be exaggerated to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention.  
         [0022]     Furthermore, elements may be recited as being “coupled”; this terminology&#39;s use anticipates elements being connected together in such a way that there may be other components interstitially located between the specified elements, and that the elements may be connected in fixed or movable relation one to the other.  
         [0023]     The present invention extends the use for lightweight concrete as disclosed in U.S. Pat. No. 5,737,896; a patent which is hereby expressly incorporated by reference for disclosure purposes.  
         [0024]     Referring to  FIGS. 1, 4 , and  9 , poured-in-place concrete components  10  are supported by-a load bearing structure  11 . The upper most horizontal slab  12  depicted in  FIG. 1  is supported by a load bearing wall  14 ; whereas the lower most horizontal slab  12  is supported by a stem wall  11  the walls  14  are supported by a load bearing structure  11 , in this case a stem wall. In both horizontal slabs  12  depicted in  FIG. 1 , support members  20 , in the form of joists, span the distance between load bearing structures  11 . As a wall  14 , support members  20  are in the form of studs which are fixed at one end region to a load bearing structure  11 . Support members  20  can also be in the form of trusses (not shown).  
         [0025]     Support members  20  can be metal, plastic, wood, or a combination thereof. Support members  20  must have sufficient dimensions and configuration to be placed in a pattern between load bearing structures  11  or  14  to reinforce a concrete component  10  for its intended purpose as a wall, floor, ceiling or roof. In a preferred embodiment, support members  20  are constructed out of light gauge metal between approximately 10 and 25 gauge steel and having a “C” cross section. It is further contemplated that the cross section of a support member  20  may be in the form of an “I”, “L”, “T”, rectangle, polygon, arc, circle or a combination thereof. For a one-story residential structure, support member  20  may be formed from 20 gauge steel.  
         [0026]     Each support member  20  may be bolted or otherwise secured to a load bearing structure  11  or  14 . The separation between support members  20  may range between 16″ to 30″ between centers. In a preferred embodiment, the spacing is approximately 28″ to 30″ between centers. Walls  14  and/or load bearing structures  11  act as an end plate to complete the creation of a segmental form  30  between structural members  20 . As shown in  FIG. 7 , reinforcing members  34  can be fixed to adjacent structural members  20  to improve the strength of a horizontal slab  10 . Furthermore, as shown in  FIG. 7 , utility conduits  80  and stubs  82  can be placed within a segmented form  30  to allow the passage of electricity, water, sewage, telephone lines, data communication lines, and the like. It is further contemplated that openings (not shown) can be formed in a concrete component  10  by placing fixed or removable inserts (not shown) with a segmented form  30 , thereby preventing a concrete slurry from occupying the space delineated by the insert.  
         [0027]     Once a segmented form is created, a lightweight concrete slurry is poured and allowed to cure (See  FIGS. 3 and 10 ). Thereafter, conventional coverings like ceiling tiles  70  ( FIG. 3 ) for ceilings or flooring  60  ( FIG. 2 ) for floors or covering  90  for walls ( FIG. 9 ) may be applied. Where a concrete component  10  requires insulation, the insulating fill material included in a lightweight concrete as described in U.S. Pat. No. 5,737,896 can be used. Where additional insulation is required, insulative material  52  like foam board is cut and placed adjacent to at least one lightweight concrete surface of a mixture  50 . In a preferred embodiment, an insulative material  52  is positioned between two layers of lightweight concrete  50  (see.  FIGS. 5 and 6 ).  
         [0028]     To form a segmented form  30 , structural members  20  are disposed within a retaining layer system  36 . A retaining layer system  36  includes a lath  32  which is dimensionally stable when affixed to and spans across at least one exterior region of adjacent structural members  20 . Such dimensional stability allows a retaining layer system  36  to retain at least a significant amount of a lightweight concrete slurry  50  within a segmented form  30 . It is further contemplated that the lath  32  has a plurality of apertures configured to allow a small quantity of a lightweight concrete slurry  50  to exude through, thereby causing securement of the lath  32  to the concrete slurry  50  when cured.  
         [0029]     In another embodiment, retaining layer system  36  includes a lath  32  affixed to one exterior region of adjacent structural members  20 ; and a form structure (not shown) removably fixed to and spanning across an exterior region opposite of the lath  32  to form a segmented form  30 . Once a lightweight concrete slurry cures in a segmented form  30 , form structure (not shown) is removed, exposing a concrete surface. In another embedment, a retaining layer system  36  includes lath  32  affixed across opposing exterior regions of adjacent structural members  20  to form a segmented form  30 . In such an embodiment, no of rm structure is required to retain a significant amount of a lightweight concrete slurry.  
         [0030]     A further alternative embodiment of a retaining layer system  36  includes a barrier  40  disposed between a substantial portion of a lath  32  and a lightweight concrete slurry  50  to significantly reduce (or even eliminate) a lightweight concrete slurry  50  from exuding through lath  32  or from the segmented form  30 . As shown in  FIGS. 2, 3 ,  4  and  9 , barrier  40  is in the form of a layer which extends between adjacent structural members  20 . As shown in  FIGS. 5 ;  7  and  10 , barrier  40  spans across adjacent structural members  20 . As shown in  FIG. 6 , barrier  40  can be disposed between a structural member  20  and a lightweight concrete  50 . It is further contemplated that barrier  40  can be place adjacent to a lath  32  to prohibit a small quantity of a lightweight concrete slurry  50  from exuding through lath  32 . In such an embodiment, lath  32  functions only to retain and form a lightweight concrete slurry  50  as it cures. It is further contemplated that in such an arrangement, lath  32  and barrier  40  could be removed after curing. Barrier  40  can be manufactured from metal, plastic, wood, composite materials and/or any other materials which eliminates or at least reduces the amount of lightweight concrete slurry  50  which could exude through lath  32 . Additionally, barrier  40  can be manufactured from materials which protect structural members  20  from moisture within adjacent lightweight concrete,  50 . Furthermore, barrier  40  can be manufactured from insulative materials to further provide insulative, qualities to a concrete component  10 .  
         [0031]     Lath  32  can be in the form of a plurality of strips fixed adjacent to each other to form a plurality of apertures (not shown). In a preferred embodiment, lath  32  is in the form of a sheet having a plurality of apertures (See  FIGS. 4, 7 ,  9  and  10 ). Whether lath  32 , is in strips or sheets, apertures are configured to primarily provide dimensional stability and secondarily allow the passage of a small quantity of a lightweight concrete slurry  50  from a segmented form  30 . Such apertures can be circular, rectangular and/or polygonal. In a preferred embodiment, metal lath typically used as an underlying structure for receiving stucco can be included in a retaining larger system  36 .  
         [0032]     A preferred segmented form  30  is constructed from a retaining layer system  36  which includes a metal lath  32  typically utilized as an underlying structure for receiving stucco on an otherwise flat surface such as a cinder block wall. A retaining, layer system  36  is placed at an outer region of structural members  20  to form a segmented form  30  to receive and confine appropriately mixed lightweight concrete  50  between structural members  20  in a poured-in-place manner. A retaining layer system  36  can be screwed or otherwise held in place against structural members  20 .  
         [0033]     Where structural members  20  are horizontal, typically there is no need for the retaining layer system  36  to confine the lightweight concrete at an upper region of a segmented form  30 . Where the structural members  20  are vertical, a segmented form  30  is created by placing structural members  20  within a reatining layer system  36  with at least one lath  36  positioned to retain a significant portion of a lightweight concrete slurry  50 . Attachment of lath  36  is achieved by screwing or otherwise holding it against structural members  20 . An alternative contemplates formation of a segmented section  30  by screwing or otherwise holding a lath  36  against an outer region of structural members  20  and opposite to a tradional form structure removably fixed to another outer region of structural members  20 . Once cured, the form structure is removed to expose a surface of the lightweight concrete  50 .  
         [0034]     The consistency of the lightweight concrete mixture  50  allows it to flow around features like utility conduits  80 , studs  82  or reinforcing members  34  within a segmental form  30 . Furthermore, the consistency of the lightweight concrete slurry  50  allows some exuding through a lath  32 . Such exuding makes lath  32  an integral part of a concrete component and further provides structural strength not unlike traditional reinforcing members placed within a concrete form.  
         [0035]     The use of lightweight concrete to replace traditional insulation in buildings provides significant benefits. One such benefit is the provision of a structure having walls, floors, ceiling and/or roofs made substantially of concrete. Previous construction using concrete panels required their fabrication off-site, then erection of the panels using a crane or other suitable lifting equipment to erect complete walls of the cured concrete panels into place. The method of forming lightweight concrete components-in-place according to the present invention obviates the need for heavy lifting equipment since the concrete  50  may be mixed in small batches before being poured into segmental forms  30 . It is possible for the lightweight concrete mixture  50  to be poured in stages to allow limited heights of concrete to set and form a base for the next insertion of insulative material  52 , upon which the next quantity of lightweight concrete mixture  50  will be poured (See  FIGS. 5, 6  and  10 ). Such an approach eliminates or at least reduces the likelihood of an insulative material  52  moving out of position.  
         [0036]     Using the poured-in-place construction method according to the present invention, creates a solid concrete component like a wall, ceiling, floor or roof, which is reinforced by structural members  20 , lath  32  and reinformcing members  34  (where used). Such a wall, floor, ceiling, or roof is non-flammable and possesses considerable strength. Once cured, the lightweight concrete slurry  50  and lath  32  provide a surface capable of resisting the strongest of impact forces, including forces generated by weather and/or foot traffic. With such attributes, structures erected with reinforced components using the methods of the present invention are ideally suited for low cost and affordable construction with concrete.  
         [0037]     These and other variations which will be appreciated by those skilled in the art are within the intended scope of this invention as claimed below. As previously stated, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various forms.