Method of forming a decorative concrete wall

Abstract

A method of constructing a concrete wall. A mold form is placed upon on a surface at a construction site. A support structure is placed into the mold form and concrete is poured around the support structure within the mold form to form a concrete panel. The upward facing surface of the poured panel is altered with one or more of a color, a texture, and a pattern to form a decorative concrete panel while the panel lies on the ground. The decorative concrete panel is then lifted into an upright position by a crane connected to lifting inserts of the panel. The lifting inserts are desirably located at a side or top end of the panel and not in the decorative surface.

Description

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of Provisional U.S. Application, Ser. No. 60/785,152, filed on 23 Mar. 2006. The co-pending provisional application is hereby incorporated by reference herein in its entirety and is made a part hereof, including but not limited to those portions which specifically appear hereinafter.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention is directed to preformed tilt-up concrete panels, i.e., preformed panels that are then lifted and set into place, such as by a crane.

2. Discussion of Related Art

Tilt-up concrete construction has been around for many years. It has developed into a preferred method of construction for many types of buildings and structures. Nationwide, over 15% of all industrial buildings are constructed using tilt-up construction, typically ranging in size from 5,000 to over 1.5 million square feet. Such buildings are typified by their attractiveness, efficiency, and longevity.

A standard practice in laying out tilt-up panels is to snap a chalk line on a concrete floor slab to indicate panel perimeters. When formed on site, forms are constructed as desired and placed against the lines. Wood boards are the most common material used for constructing side forms. Often the panel depth is designed to fit the depth of standard dimension lumber, so 5.5 and 7.25 inch-thick structural panels are common. Door and window openings are generally formed after framing the panel perimeter.

The forms can be supported and secured to the slab by wood or steel angle supports. Any common concrete anchor can be used to attach supports and/or forms to the slab. Any holes in the slab left by anchors will be repaired after lifting the formed panel. Inside the forms, the desired wall support structure is placed. Such support structure is often formed by metal rods, steel grid, or rebar, as is generally known in constructing concrete walls. The support structure should be lifted off the ground and “float” within the side form to ensure the desired central placement within the wall. Embeds and inserts are added to the side forms. Embeds are pre-fabricated steel plates with lugs that are cast into the panel to attach it to the footing, other panels, or the roof system, or for attachment of building accessories after the shell is completed. They can be attached to the forms if they are on the panel edges, or they can be wired to the reinforcing structure. As shown in FIGS. 1 and 2, inserts provide the attachment points for lifting hardware 10 and braces, and are generally disposed in the surface 12 that faces upward, to allow the attachment of the lifting crane 14 to the upward facing surface 12 (which is the interior surface of the erect wall).

Compressed air can be used to clean the floor within the form. A form release agent and/or bond breaker is desirably applied to the floor slab, and concrete is poured into the form and around the support structure. The outward facing surface of the tilt-up panel is the bottom of the pour, where the concrete meets the form or floor. Any desired pattern for the panel is applied by placing molds or strips in the bottom of the form and pouring the concrete on top. A trowel finish to the upward facing surface is suitable for most projects.

After pouring, the inserts and embeds are located and cleaned. Braces 16 are often attached before lifting the panels with a crane, as shown in FIG. 2. The braces 16 typically remain until after the roof and decking are installed. Once the braces 16 are removed, holes in the floor can be patched.

Current processes of creating a decorative concrete pre-cast or tilt-up concrete panel consist of pouring concrete above, for example, a form liner or thin pieces of stone-brick-slate or rock placed on the bottom of the form, thereby producing these desired finished looks when the concrete panel is erected. Form liner materials need to be fitted in place prior to installing reinforcement and any insulation material, and great care needs to be taken not to damage these forms while pouring concrete, especially if vibrating the concrete is required. These current methods make the use of insulation within these concrete panels extremely difficult and costly, if not completely impractical. Insulation installed within concrete pre-cast or tilt-up panels represents a huge energy efficiency advantage, and often leads to the decision to use concrete pre-cast or tilt-up construction, in locations with colder climates. Vibrating the concrete also becomes very difficult if not impractical. There is also no way to “finish” (trowel or smooth) the downward facing concrete surface prior to applying the decorative finish. The labor does not end with the installation of form liner materials prior to pouring the concrete. Upon erection of the pre-cast or tilt-up wall panels much labor time is spent in complete removal of form liner material as well as touch up work necessary to produce an acceptable finished product.

Various finishes can also be applied after placing the lifted panel in place. Sandblasted or exposed aggregate finishes can be done immediately after panel erection. Painting, however, must generally wait until partial curing has taken place and residue from the bond breaker has been removed. Coloring must either be done to the entire concrete, thereby increasing cost, or after the panels are lifted into place, thereby requiring additional equipment and increased safety concerns for working high above the ground.

There is a need for an improved method of forming a decorative preformed concrete panel than can be lifted and set into place.

SUMMARY OF THE INVENTION

A general object of the invention is to provide a method for facilitating forming a decorative concrete wall panel for use in tilt-up concrete applications.

The general object of the invention can be attained, at least in part, through a method of constructing a concrete wall. The method includes: providing a decorative concrete panel (made either on-site or at a remote location), including a decorative surface, at a construction site; placing the decorative concrete panel on a surface at the construction site with the decorative surface facing upwards and away from the surface; and lifting the decorative concrete panel into an upright position to sit in place (at the construction site) on a panel end adjacent the decorative surface.

The invention further provides a method of constructing a concrete wall including: laying a mold form on a surface at a construction site; placing a support structure into the mold form; pouring concrete around at least a portion of the support structure within the mold form to form a concrete panel; altering an upward facing surface of the concrete panel with at least one of a color, a texture, or a pattern to form a decorative concrete panel; and lifting the decorative concrete panel into an upright position.

The present invention relates to poured concrete pre-cast or tilt-up concrete walls for residential homes, commercial/industrial buildings, or for concrete retaining wall construction. The method of one embodiment of this invention is, in one sense, generally done opposite of current methods to produce a decorative finish to the face of a pre-cast or tilt-up concrete wall panel before lifting. As discussed above, existing methods require a template or “form liner” of whatever pattern or design of choice placed on the bottom of the wall pour, underneath the rebar reinforcement. The concrete then is poured over the pattern and when the wall panel is tilted up into place the form liner material is removed revealing the finished decorative face.

The method of this invention is an improvement over current processes, such as using a form liner installed prior to pouring a pre-cast or tilt-up concrete wall, which are time consuming, labor intensive processes used to add a brick-stone-slate-rock simulated look to a poured concrete pre-cast or tilt-up wall. The method of this invention allows for relatively faster construction. In one embodiment of this invention, the decorative finish is applied before lifting, and when the wall panel is erected no further work needs to be done to the decorative finish. Other advantages of this invention include: the color does not have to be mixed into the entire wall panel, and can be applied to the surface only before lifting, thereby reducing cost; variations of color and many different colors can be applied to the panel before it is erect, thereby allowing for more decorative options; and the method of this invention is relatively safer as this decorative process is complete on the ground prior to erection of new wall panels.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects and features of this invention will be better understood from the following detailed description taken in conjunction with the drawings, wherein:

FIG. 1 illustrates an example representation of a currently used tilt-up panel;

FIG. 2 generally illustrates the lifting of the panel of FIG. 1;

FIG. 3 shows the mold form and support structure for forming a concrete panel according to one embodiment of this invention;

FIG. 4 illustrates the coloring of a surface of a poured panel according to one embodiment of this invention;

FIG. 5 generally illustrates a lifting of the panel of FIG. 4; and

FIG. 6 illustrates a partial building formed of multiple tilt-up panels according to this invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

According to one embodiment of this invention, a decorative concrete wall is produced at a construction site where the wall will be used. To create the wall panel on site, a mold form is created and laid on a flat surface, such as, for example, an already formed concrete floor structure. The mold form is desirably made from wood boards, or steel, and is made according to the size and shape of the desired concrete wall panel. The mold form is the outside perimeter of the wall panel, and also desirably includes internal forms for any doors and/or windows that are to be formed within the perimeter of the wall panel.

FIG. 3 illustrates a partial view of a mold form 20. Once the mold form 20 is created, a support structure 30 is placed into the mold form 20. The support structure 30 can include any suitable concrete support known and available to those skilled in the art. For example, a combination of steel grid 32 and rebar 34 can be used to form the support structure 30, as shown in FIG. 3.

The concrete panel to be formed within mold form 20 is formed on the ground or concrete floor and lifted into an upright position to stand on a bottom edge. In order to lift the formed wall panel, the wall panel should include places to connect cables from the crane that will do the lifting. Until now, such connection places have been disposed along the upward facing surface of the wall panel (which is the rear of the wall panel once erect). In one embodiment of this invention, a plurality of lifting inserts 40 extend from the panel sides disposed at an angle, e.g., perpendicular, to the upward facing surface. Desirably, no lifting inset 40 is placed in the upward facing surface of the panel to be decorated. If, depending on need, one or more inserts are needed in the upward facing surface, desirably these inserts are placed to be hidden in the intended pattern or texture of the panel surface.

As shown in FIG. 3, the inserts 40 are tied, welded, or otherwise connected to the support structure 30. In FIG. 3, the inserts 40 included extensions 42 that are desirably welded together to a similar extension of an adjacent insert 40. In one embodiment of this invention, the inserts 40 can be used to assist in holding the support structure 30 off the surface under the mold form 20, thereby allowing concrete to envelope the support structure 30 when poured. The inserts 40 are desirably threaded, and a bolt 46 can extend through the side of the mold form 20 to thread into one of the inserts 40. The bolts 46 help hold the support structure 30 in place during concrete pouring. Various and alternative sizes, shapes, placements and configurations are available for the inserts according to this invention. For example, the inserts can alternatively be placed in an intended top end of the panels instead of or in addition to the sides as shown.

After the support structure 30, and any optional insulation material, is placed into the mold form 20, the mold form 20 is filled with concrete. The concrete can be applied into the mold form 20 by any method currently used in tilt-up construction. The concrete can be poured around the support structure 30 to form a concrete panel, desirably leaving the inserts 40, and any other included embeds, accessible for assembling the panel in place. FIG. 4 shows a poured concrete panel 50 within mold form 20. As shown in FIG. 4, mold form 20 is held into place by angle supports 44, which can be attached to the floor. Once the concrete is poured, the concrete is desirably vibrated, as is known to those skilled in the art, to ensure the support structure 30 is surrounded and secure.

The method of this invention allows for the decoration of the concrete panel prior to lifting into place. There is no intended limit to the scope of aesthetic decorations that can be applied to the upward facing surface 52 of the poured concrete panel 50. The upward facing surface can be altered by one or more of a color, a texture, or a pattern. Any concrete colorant can be used to color the surface 52 of panel 50. The colorant can be a powder, either blended with the concrete or applied to a poured concrete surface, such as shown as powder colorant 56 being applied in FIG. 4. The colorant can also be a liquid, such as known paints useful for painting concrete, stains, or other chemicals known for use in altering the natural color of the concrete panel. Texture can be applied by various methods, such as using an embossing or texturizing roller or rake. Patterns can also be applied by various and alternative methods. Referring to FIG. 4, surface 54 includes two decorative grooves 58, which can be formed by inserts at the bottom of the mold form 20, or simply using a trowel. As other non-limiting examples, molds or other stamping tools can be used to impart patterns, such as a brick or stone pattern, to the surface 52. Suitable molds are commonly used in forming concrete patterns for driveways and walkways. Suitable colorants and molding or stamping tools are available from Butterfield Color, Aurora, Ill.

Once the upward facing surface 52 of the panel 50 is decorated as desired and the concrete has sufficiently dried, the mold form 20 is removed. The necessary lifting hardware is inserted into the inserts 40, and the concrete panel 50 is lifted into an upright position and placed at the desired location. As shown in FIG. 5, a metal eyelet 60 is screwed into each of the inserts 40. Cables 62 connect a crane to the eyelets 60. As is known in the field of tilt-up concrete panels, one or more cranes then lifts the concrete panel 50 into place to stand on a bottom end 64.

FIG. 6 shows a building 70 being constructed from a plurality of decorative concrete panels made according to this invention. Each of the plurality of decorative concrete panels is held in position by a brace. When an adjacent panel is placed, the two adjacent panels are attached and sealed, such as by using methods and materials currently employed in tilt-up construction. The intended placement of panel 50 is shown at a rear edge by dashed outline 72. Other seams between panels are shown for illustration purposes by dashed lines 74.

Thus the invention provides an improved method of constructing decorative tilt-up concrete panels for forming walls and ultimately buildings or other structures. The panels can be formed on site or at a remote site using the same techniques and then transported to the construction site for lifting into place. The method of this invention allows for easier, safer, and thus cost effective decorative altering of a panel surface. By decorating the upwards facing panel surface, one can see the pattern and exert more control over the decorating, thereby requiring fewer concrete repairs once erected.

It will be appreciated that details of the foregoing embodiments, given for purposes of illustration, are not to be construed as limiting the scope of this invention. Although only a few exemplary embodiments of this invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention, which is defined in the following claims and all equivalents thereto. Further, it is recognized that many embodiments may be conceived that do not achieve all of the advantages of some embodiments, particularly of the preferred embodiments, yet the absence of a particular advantage shall not be construed to necessarily mean that such an embodiment is outside the scope of the present invention.

Claims

1. A method of constructing a concrete wall, the method comprising:

providing a decorative concrete panel at a construction site, the decorative concrete panel including a decorative surface;

placing the decorative concrete panel on a surface at the construction site with the decorative surface facing upwards and away from the surface; and

lifting the decorative concrete panel into an upright position to sit in place on a panel end adjacent the decorative surface.

2. The method of claim 1, wherein providing the decorative concrete panel at the construction site comprises forming the decorative concrete panel at a remote site and transporting the decorative concrete panel to the construction site.

3. The method of claim 1, wherein providing the decorative concrete panel at the construction site comprises forming the decorative concrete panel at the construction site.

4. The method of claim 3, wherein placing the decorative concrete panel on the ground with the decorative surface facing upwards and away from the ground comprises forming a concrete panel in a mold form on the ground and altering an upward facing surface of the concrete panel with one of a color, a texture, or a pattern to form the decorative surface.

5. The method of claim 4, additionally comprising applying a colorant to the upward facing surface of the concrete panel.

6. The method of claim 4, additionally comprising applying a decorative mold to the upward facing surface of the concrete panel and applying pressure to the decorative mold to form the texture or pattern.

7. The method of claim 1, wherein the decorative concrete panel includes a plurality of lifting inserts extending from at least one panel side disposed at an angle to the decorative surface.

8. The method of claim 7, wherein lifting the decorative concrete panel comprises lifting the decorative concrete panel by the lifting inserts with a crane.

9. The method of claim 7, wherein no lifting insert is disposed in the decorative surface.

10. A method of constructing a concrete wall, the method comprising:

laying a mold form on a surface at a construction site;

placing a support structure into the mold form;

pouring concrete around at least a portion of the support structure within the mold form to form a concrete panel;

altering an upward facing surface of the concrete panel with at least one of a color, a texture, or a pattern to form a decorative concrete panel; and

lifting the decorative concrete panel into an upright position.

11. The method of claim 10, additionally comprising coloring the upward facing surface of the concrete panel.

12. The method of claim 11, additionally comprising mixing a colorant with the concrete.

13. The method of claim 11, additionally comprising applying a colorant to the upward facing surface of the concrete panel.

14. The method of claim 13, wherein the colorant is applied as a powder.

15. The method of claim 13, wherein the colorant is applied as a liquid paint or stain.

16. The method of claim 10, additionally comprising applying a texture or pattern to the upward facing surface of the concrete panel.

17. The method of claim 16, additionally comprising applying a decorative mold to the upward facing surface of the concrete panel and applying pressure to the decorative mold to form the texture or pattern.

18. The method of claim 10, wherein the support structure includes a plurality of lifting inserts extending outward from a side of the concrete panel adjacent the upward facing surface for use in lifting the decorative panel.

19. The method of claim 18, additionally comprising lifting the decorative concrete panel by the lifting inserts with a crane.

20. A building formed at least in part by the method of claim 10.