WO2008089414A1

WO2008089414A1 - Building panel for walls, roofs and floors, buildings made therefrom and construction techniques using such panels

Info

Publication number: WO2008089414A1
Application number: PCT/US2008/051446
Authority: WO
Inventors: Errett Everon Elmer; Janusz Andrzej Krysinski; Jan Urbanowicz
Original assignee: Errett Everon Elmer; Janusz Andrzej Krysinski; Jan Urbanowicz
Priority date: 2007-01-19
Filing date: 2008-01-18
Publication date: 2008-07-24

Abstract

A building panel for walls, floors and roofs has an inner region defined by a pre- stressed concrete panel, metal or plastic studs or other construction articles. The region is at least partially filled with expanded concrete. In a preferred construction the expanded concrete includes up to about 80% of its holding capacity for air.

Description

BUILDING PANEL FOR WALLS. ROOFS AND FLOORS. BUILDINGS MADE THEREFROM AND CONSTRUCTION TECHNIQUES USING SUCH PANELS

BACKGROUND OF THE INVENTION

1. Field of the Invention

[0001] The present invention relates to generally to building construction and, more particularly to building panels assembled one to another in constructing buildings and, still more particularly, to concrete building panels and the construction of buildings using such panels.

2. Description of the Related Art

[0002] Building construction involves numerous competing desires and objectives for builders and building owners alike. It is desirable for buildings to be strong, durable and long lasting. However, it is also desirable for construction of buildings to be efficient, quick and completed at a reasonable and acceptable expense. Combining these and other competing factors is a challenge for both builders and building owners. [0003] Different construction techniques have been and are used, and construction techniques can vary from one region to another region, from one builder to another builder, and from one type of building to another type of building. However, regardless of the region, builder or type of building, value is achieved by maximizing the competing interests as much as possible.

[0004] Known construction techniques include the piece-by-piece fabrication of a frame, which can be of metal, wood or other materials, and the subsequent application of both interior and exterior surfaces. It is known to perform these tasks on site, as the building is erected. The process can be time consuming and expensive. While some so- called "prefabricated" construction techniques are known, they are not universally accepted, and to some builders and building owners prefabrication has a connotation of lower quality. Further, some of the known prefabrication techniques simply involve the construction of discrete building components off site using standard techniques of piece- by-piece fabrication of a frame and subsequent application of both interior and exterior surfaces. The added efficiency of constructing off site under controlled conditions with standardized materials, sizes and the like can yield some cost savings, but the process remains labor intensive. Cost-reducing construction techniques and products that do not compromise quality can provide advantages for builders and building owners. [0005] In some situations, rapid construction of buildings is of great value. For example, when a city or region has suffered catastrophic losses from natural phenomena such as tornadoes, hurricanes, fire, earthquakes, tsunamis and the like it is necessary to construct quickly many buildings of different types and purposes, including residential structures; public buildings such as schools, police and fire stations, governmental offices, public service buildings and the like; commercial buildings and industrial buildings. Recovery of the individuals and the community as a whole is enhanced if the reconstruction occurs quickly, allowing the resumption of normal personal and social activities. However, rapid construction of buildings is of less advantage if quality is compromised.

[0006] In areas that frequently experience potentially catastrophic natural phenomena, such as tornadoes, hurricanes, earthquakes, tsunamis and the like, it is desirable to construct new buildings with decreased vulnerability to damage from such events. Construction techniques and products that improve construction efficiency without compromising quality also can provide advantages for builders and building owners. [0007] Low cost yet durable construction is also of importance in poor and developing regions. Quality, yet affordable construction can be a valuable component to the development or recovery of a community.

[0008] Accordingly, what are needed are building components, construction techniques and buildings made therefrom that combine features of strength, durability, rapid construction and low cost for use in buildings of all types, including residential, public, commercial and industrial buildings.

SUMMARY OF THE INVENTION

[0009] The present invention provides building panels that can be made in a variety of sizes with known construction components such as pre-stressed concrete slabs or standard frame components and are filled with expanded concrete, thereby providing at least rough finished surface interior and exterior walls, roofs and floors with insulated interiors. The panels can be used for walls, floors and roofs and can be suitable for buildings of all types.

[0010] In one aspect of one form thereof, the present invention provides a building panel for walls, roofs and floors with at least one boundary article defining a region, expanded concrete filling at least a portion of the region; and the at least one boundary article providing means for connecting adjacent building panels

[0011] In another aspect of another form thereof, the present invention provides a process for constructing at least one of a wall, a roof and a floor of a building, with steps of forming a panel having a region defined by one of pre-stressed concrete, metal and plastic; filling at least a part of the region with expanded concrete; curing the expanded concrete; transporting a plurality of such panels to a construction site; positioning the plurality of panels adjacent one another in at least one of a wall, a floor and a roof of a building being constructed; and connecting adjacent panels in the at least one of a wall, a floor and a roof to each other. [0012] In still another aspect of still another form thereof, the present invention provides a building with a plurality of wall panels and a plurality of roof panels, each panel of the pluralities of panels having at least one boundary article defining a region; expanded concrete filling at least a portion of the region; and the at least one boundary article providing means for connecting adjacent panels of the pluralities of panels. [0013] An advantage of the present invention in one form is providing a building panel in different sizes and adaptable for different uses including use in walls, floors and roofs. [0014] Another advantage of the present invention in another form is providing a building panel that is strong and durable, and that can be installed in a building structure efficiently.

[0015] Still another advantage of still another form of the present invention is providing a strong, durable, non-flammable building panel suitable for use in buildings of all types. [0016] Still another advantage of the present invention in still another form is providing a building structure using panel construction having strength, durability and fire resistance.

[0017] Still another advantage of the present invention in yet another form is providing a method of constructing buildings including the connection of adjacent prefabricated panels in walls, floors and roofs.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein: [0019] Fig. 1 is a fragmentary cross-sectional view of a building in accordance with the present invention using building panels of the present invention;

[0020] Fig. 2 is a cross-sectional view of one of the building panels shown in Fig. 1;

[0021] Fig. 3 is a cross- sectional view of the building panel shown in Fig. 2, the view having been taken along line 3-3 of Fig. 2;

[0022] Fig. 4 is a cross-sectional view of adjacent building panels according to another embodiment of the present invention;

[0023] Fig. 5 is a cross-sectional view of the building panels shown in Fig. 4, the view having been taken along line 5-5 of Fig. 4;

[0024] Fig. 6 is an enlarged fragmentary cross-sectional view of a building panel of the present invention, the panel being shown under fabrication;

[0025] Fig. 7 a fragmentary view of a building panel of the present invention; and

[0026] Fig. 8 is a fragmentary cross-sectional view of a building in accordance with the present invention using building panels of the embodiment shown in Fig. 4.

[0027] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate embodiments of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.

DETAILED DESCRIPTION OF THE INVENTION

[0028] Referring now more specifically to the drawings and to Fig. 1 in particular, a fragmentary cross-sectional portion of a building 10 is shown. Building 10 includes wall panels 12, floor panels 14 and roof panels 16, each provided in accordance with the present invention. Adjacent wall panels are connected by surrounding beams 18 that are also used for connecting adjacent wall and floor panels. Surrounding beams 18 also are used for connecting adjacent wall panels 12 with roof panels 16. Adjacent roof panels 16 are connected by connecting beams 20, as are adjacent floor panels 14. [0029] In the exemplary embodiment of Fig. 1, wall panels 12, floor panels 14 and roof panels 16 have a similar base construction, but with potentially different surface finishes. Each panel 12, 14 or 16 includes a known concrete slab 30 (Fig. 2), sometimes referred to as a "U-panel," having a boundary including sides 32 and an interconnecting web 34. Sides 32 are provided along and surround the edge of web 34, and extend substantially at right angles to web 34 at one face thereof. Web 34 is of thickness less than the height of sides 32 such that a defined region or cavity 36 is provided outwardly of one face of web 34 and between the sides 32 extending outwardly thereof. A plurality of ribs 38 project into cavity 36 defined by slab 30, which is open above web 34 and between the sides 32. In the exemplary embodiment shown, two ribs 38 are provided; however, it should be understood that more or fewer ribs 38 can be used. In small panels, ribs may not be necessary. Further, it should be understood that sides 32, web 34 and ribs 38 can be formed as a monolithic body during the fabrication of slab 30. Cavity 36 is filled with expanded concrete 40.

[0030] Slab 30 is formed of concrete, and maybe reinforced concrete, and preferably is prestressed concrete. In reinforced concrete, the tensile strength of steel is combined with the compressive strength of concrete to form a structural member that is strong in both compression and tension. In a preferred prestressed slab 30, high-strength steel tendons 42 are stretched across a casting form before the concrete slurry is poured therein. After the concrete has cured, the tendons are released from the mold fixture, and the tendons induce compressive stresses to balance tensile stresses placed on the member during use. The methods of manufacturing concrete slabs, reinforced concrete slabs and prestressed concrete slabs are well known to those skilled in the art and will not be described in further detail herein. Further, the form and configuration of slab 30 shown is merely exemplary, and other shapes and configurations thereof also can be used. [0031] Expanded concrete is known for other uses. Expanded concrete, also sometimes referred to as "cellular concrete," incorporates a significant volume of air into the concrete slurry before curing, so that voids or pockets are established in the cured concrete, for purposes other than building panels. It has been known to use between about 30% and 50% air in expanded concrete, based on the total air holding capacity of the concrete. In one preferred construction of the present invention up to about 80% air is incorporated into the expanded concrete for panels of the present invention. Accordingly, a network of voids, pockets or air bubbles 44 is created in the slurry and remains as the slurry cures and hardens. There are known techniques for injecting or creating air bubbles 44, including mechanical injection in the slurry and bubble generation from chemical additives provided in the slurry to create foam. Further, it should be understood that the voids in the finished concrete can be a network of irregularly shaped pockets, some interconnecting with others, and not simply a plurality of discrete regularly shaped bubbles or voids. For clarity, only some but not all bubbles or voids 44 have been designated with reference numerals in the drawings.

[0032] To improve strength and stability of the aerated expanded concrete, a fibrous material can be added. Fibers 46 can be natural or synthetic, and preferably are lightweight. Polypropylene fibers are suitable. For clarity, only some but not all fibers 46 have been designated with reference numerals in the drawings.

[0033] In one acceptable construction, the pre-stressed panel is made from slurry that includes Portland cement in an amount of about 25% by weight, sand in an amount of about 50% by weight and gravel in an amount of about 25% by weight. Water is added to form slurry from which the slab is formed in conventional manner. Steel reinforcement or prestressing tendons are provided in the slab. The manner of construction for pre- stressed slab 30 is known to those skilled in the art. A known slab 30 has an overall width of up to about 4 feet and a common overall length of about 8 feet to about 12 feet. Still longer slabs of 20 feet to about 40 feet also can be used. The thickness of slab 30 from the outer surface of web 34 to the opposite edge of sides 32 can be standard sizes, such as about 6 inches to about 20 inches. The thickness of web 34 is about 1.5 inch to about 2.5 inch. U-shaped concrete slabs of various standard construction sizes can be used.

[0034] The fill of expanded concrete provided in cavity 36 includes slurry formed with about 80% by weight Portland cement type 30, and 15% by weight fly ash. Approximately 5% Silica Fume SFlOO from Master Builders is added. A super plasticizer such as EUCO 37 is added in an amount of about 50 grams per 10 liters of water used to mix the dry components and form slurry. Further, an accelerator such as EUCO Accelerator H-E is added in an amount of about 100 grams per 10 liters of water in the slurry. Approximately 1 kilogram of polypropylene fiber is added per cubic meter of the expanded concrete. The slurry is aerated with between at least about 40% to about 80% of the total air carrying capacity of the slurry. Aeration with between about 40% and about 70% of the total air carrying capacity of the expanded concrete slurry is a readily attainable, acceptable range. The expanded concrete slurry is placed in the preformed slab 30 to substantially fill the void therein defined by region 36. [0035] To provide a smooth finished surface, a cement board 48 can be used to cover the exposed surface of expanded concrete 40. A suitable cement board formulation includes Portland cement type 30 in an amount of about 25% by weight, fly ash in an amount of about 45% by weight and sand such as "Litex" from Master Builders in an amount of about 25% by weight. Master Builders Silica fume SFlOO in an amount of about 5% by weight is used. About 100 g. of EUCO 37 Super Plasticizer and about 100 g EUCO Accelerator H-E are used for each 10 liters of water used to make the concrete slurry. Air bubbles are generated in the slurry by adding about 15% of the total air carrying capacity of the slurry. Polypropylene fibers are added for reinforcement. A fiberglass mesh is used also for reinforcement, the mesh being approximately 2.5 mm x 2.5 mm. A bonding agent such as SBR Latex Acrylic is applied for adhesion. Cement board 48 is hard and durable.

[0036] A summary of the composition of a wall panel 12, floor panel 14 or roof panel 16 is as follows:

Cement Board formulation (% by weight)

25 % Portland cement type 30

45% Fly Ash (Burned Coal)

25% Sand type "Litex" (Master Builders)

5% Silica Fume SFlOO (Master Builders)

100 g Superplasticizer/10 L of water (EUCO 37)

100 g Accelerator H-E/ 10 L of water (EUCO)

15% Air Bubbles (by total capacity) (EUCO)

Ikg/m3 Polypropylene fiber

2.5x2.5 mm Fiberglass Mesh (top and bottom)

Water coefficient - 0.45

Acrylic bonding - spray on exterior face of board (SBR Latex)

Cellular Concrete formulation (% by weight) 80% Portland cement type 30 15% Fly Ash (Burned Coal) 5% Silica Fume SFlOO (Master Builders) 50 g/10 L of water Superplasticizer (EUCO 37) 100 g/ 10 L of water Accelerator H_E (EUCO) 40 - 70 % (by total capacity) air bubbles (EUCO) Ikg/m3 Polypropylene fiber Water coefficient - 0.45 Pre-stressed slab formulation (% by weight)

25% Portland cement

50% Sand

25% Gravel

Steel reinforcement

[0037] Fig. 6 illustrates a process that can be used to provide a smooth exposed surface without the use of the cement board 48. As the slurry of expanded concrete 40 cures, the exposed surface can be subjected to a vibrator 50. A mesh of fiberglass or the like can be used advantageously just below the surface of the expanded concrete 40. Vibration of the exposed surface of expanded concrete 40 dispels air bubbles 44 that are close to the surface. Accordingly, a substantially smooth skin 52 is provided on expanded concrete 40. The exposed surface of expanded concrete 40 is then suitable for application of surface finishes similarly to cement board 48. Surface finishes can include, but are not limited to plaster, concrete, paint, sheeting of various types and other surface finishes suitable for the structure in which the panel of the present invention is used as a wall panel 12. When used as a floor panel 14, surface finishes such as, for example and not limitation, carpeting, ceramic and various types of tile, stone, brick, wood and the like can be used. When used as a roof panel 16, roof surfaces of various types can be used, including individual shingles and composite surfaces of rubber, tar, gravel, etc. When further insulation is required, Styrofoam board can be glued directly to the wall, floor and/or roof panels of the present invention using an appropriate adhesive. [0038] In an alternative embodiment for a panel 100 (Figs. 4, 5 & 7) of the present invention, a plurality of conventional wall studs 102, preferably made of metal or plastic, are fastened one to another to define the perimeter of a region or cavity 104. Pieces of cement board 106, 108, which in composition are similar to cement board 48, extend along the lengths of studs 102 and span the regions between studs 102, respectively. Cement board pieces 106, 108 can be held to studs 102 by fasteners 110, adhesive or other suitable attaching means. Cement board edge pieces 106 extending along the lengths of studs 102 and surface pieces 108 spanning the region between the studs 102 can be used for containing a slurry of expanded concrete 140 that is provided into cavity 104. Cement board pieces 106, 108 are similar to cement board 48 described previously, and expanded concrete 140 is similar to that described previously for expanded concrete 40, including bubbles 144 formed therein and fibers 146 provided therein. For clarity, only some but not all bubbles or voids 144 and fibers 146 have been designated with reference numerals in the drawings.

[0039] Fig. 8 illustrates a building 210 using panels as described for panel 100 for wall panels 212, floor panels 214 and roof panels 216. Building 210 is supported on a foundation 218, and can be held by pins 220.

[0040] Panels of the present invention can be manufactured efficiently in a dedicated plant and subsequently transported to a construction site. Slab 30 as described using a prestressed slab is suitable for use in supporting situations such as support walls, floors and the like. Panels 12, 14, 16 using slab 30, especially a pre-stressed slab 30, are suitable for use in larger buildings and towers. Panel 100 is suitable in lower load carrying applications such as smaller buildings, interior walls of larger buildings, or the like. Panels 12, 14, 16, 100, 212, 214 and 216 can be provided in standard dimensions, or can be made in custom sizes. Openings for windows, doors, skylights, stairways or elevators and other openings can be defined in the manufacture of panels 12, 14, 16, 100, 212, 214 and 216 so that on-site formation of the openings is not required. [0041] Known fastening techniques can be used to secure adjacent panels to one another. For example, in situ poured cement connecting beams 20 and surrounding beams 18 and vertical columns can be used together with panels 12, 14 and 16 that define channels 230 along the outer edges there of to receive the in situ poured concrete. Adjacent panels 100 can be connected one to another using fasteners 232, such as screws, in an "x" or crossed configuration, as shown in Fig. 4.

[0042] It should be understood that a building 10 can use different size panels of the present invention and panels of the present invention constructed in different ways in accordance with different embodiments of the present invention. After installation, the exposed interior and exterior surfaces of panels 12, 14, 16, 100 can be finished in suitable manner. Cement paint can be applied directly to the exposed surfaces, including expanded concrete 40, slab 30 and/or cement board 48. Surface finishes such as tile, carpeting, roof shingles 234, roof gutters 236 and the like are readily attachable to or can be applied on the panels, beams and building structure of the present invention. For the installation of utility services, such as electrical lines, plumbing and the like, panels of the present invention are manufactured for specific projects with plastic channels extending there through to receive pipes, wires and the like.

[0043] Panels of the present invention incorporating expanded concrete provide improved thermal insulation, sound deadening and the like. Buildings constructed using panels of the present invention can be manufactured quickly by the erection and attachment of large panels of the present invention. It is anticipated that a three-worker crew with a crane will be able to assemble approximately 1000 ft.² of loadbearing walls and slab panels in an eight-hour workday. Buildings constructed in accordance with the present invention are strong and resistant to wind and fire from the use of strong and noncombustible materials. Accordingly, buildings properly constructed using panels of the present invention provide improved earthquake resistance, hurricane resistance and fire resistance. Thermal and sound insulating properties are very high [0044] While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A building panel for walls, roofs and floors, said building panel comprising: at least one boundary article defining a region; expanded concrete filling at least a portion of said region; and said at least one boundary article providing means for connecting adjacent said building panels.

2. The building panel of claim 1, said at least one boundary article being a pre- stressed concrete slab.

3. The building panel of claim 1, said boundary article including sides defining a perimeter of said region and a web spanning said region.

4. The building panel of claim 3, said web and sides being prestressed with tendons embedded therein.

5. The building panel of claim 3, including ribs extending from said web into said region.

6. The building panel of claim 5, said means for connecting adjacent panels including channels along edges of said panels.

7. The building panel of claim 1, said means for connecting adjacent panels including channels along edges of said panels.

8. The building panel of claim 1, said at least one boundary article being multiple wall studs.

9. The building panel of claim 8, said studs being one of plastic and metal.

10. The building panel of claim 9, including cement board attached to said studs.

11. The building panel of claim 1, said the expanded concrete having a network of voids therein, said voids defining a volume of up to about 80% of the total air carrying capacity of a concrete slurry from which said expanded concrete is formed.

12. The building panel of claim 1, said the expanded concrete having a network of voids therein, said voids defining a volume of at least about 40% of the total air carrying capacity of a concrete slurry from which said expanded concrete is formed.

13. The building panel of claim 1, said expanded concrete including Portland cement in an amount of about 80% by weight and fly ash in an amount of about 15% by weight.

14. The building panel of claim 1, said expanded concrete having reinforcing fibers therein.

15. The building panel of claim 14, said fibers being poly propylene fibers in an amount of about 1 kg per cubic meter of said expanded concrete.

16. A process for constructing at least one of a wall, a roof and a floor of a building, said process comprising: forming a panel having a region defined by one of pre-stressed concrete, metal and plastic; filling at least a part of the region with expanded concrete; curing the expanded concrete; transporting a plurality of such panels to a construction site; positioning the plurality of panels adjacent one another in at least one of a wall, a floor and a roof of a building being constructed; and connecting adjacent panels in the at least one of a wall, a floor and a roof to each other.

17. The process of claim 16, including constructing at least two of a wall, a floor and a roof of a building by said steps of forming, filling, curing, transporting, positioning and connecting.

18. The process of claim 16, including forming all three of a wall, a floor and a roof of a building by said steps of forming, filling, curing, transporting, positioning and connecting.

19. The process of claim 16, including vibrating at least an exposed surface of the expanded concrete for at least a portion of said he curing step.

20. A building comprising: a plurality of wall panels and a purality of roof panels, each panel of said pluralities of panels comprising: at least one boundary article defining a region; expanded concrete filling at least a portion of said region; and said at least one boundary article providing means for connecting adjacent panels of said pluralities of panels.