High tensile grid module for use in concrete construction and method of use

Abstract

A plurality of concrete reinforcing grid modules each comprising a plurality of spaced longitudinal wires and a plurality of spaced transverse wires may be nestably stacked together and sold as a package. The transverse wires are secured to the longitudinal wires at intersections. Each grid module may be secured to other like grid modules without the use of tools or additional material because least some of the grid module wires have tail portions at the ends thereof which interlock with the wires of other grid modules.

Description

FIELD OF THE INVENTION

This invention relates generally to a method and apparatus for use in steel reinforced concrete construction and, more particularly, to a pre-assembled stackable grid module and associated method of use.

BACKGROUND OF THE INVENTION

One of the most prevalent articles used to reinforce concrete structures is a steel reinforcing bar, commonly abbreviated and referred to as “rebar.” Rebar is useful in constructing a variety of residential and commercial structures including building foundations, dams, parking garages, retaining walls, bridges, garages and sidewalks. Specifically, rebar is used to reinforce concrete structures exposed to heavy tensile, compressive and shear stresses. Conventional rebar is milled into cylindrical rods of substantial length which may include ribs.

Such long reinforcing bars are difficult to load and transport.

The rods must be cut to the appropriate size and individually placed in position in a reinforcing mesh and the intersections individually tied or otherwise affixed together as shown in U.S. Pat. Nos. 5,881,460 and 6,128,882 for example. Constructing reinforcing meshes for irregularly shaped areas is often difficult, requiring the cutting, bending and fitting of the bars or rods to adapt to the irregular dimensions and contours of the areas.

Another known product for concrete reinforcement is rolled wire mesh. Such rolls are difficult to flatten and wants to return to its rolled, curved condition. Such wire mesh must be cut to its desired size and appropriately positioned prior to the pouring of the concrete, a labor intensive task.

For constructing walk ways and patio floors, concrete is typically poured in 3.5 to 4.5 inch thick forms having wire products or rebar centered in the concrete pad to improve the strength of the concrete. If the strengthening member is a wire mesh, it must be positioned in the right position relative to the ground or substrate. Consequently, the wires of the mesh are inserted and held in receptacles in what are known in the industry as chairs or risers. During the pouring of the wet concrete these chairs or risers often are knocked over or moved by the weight of the wet concrete, thereby moving the wire strengthening members to undesirable locations. This may lead to weak spots in the concrete once it hardens which are susceptible to cracks subsequently.

U.S. Pat. No. 3,950,911 discloses modular units or grids of reinforcing mesh which are small enough to be carried by an individual and may be connected to reinforce concrete. However, such modular grids, like other pieces of rebar, are made of conventional wire having a tensile strength of between 65,000 and 75,000 pounds per square inch (“psi”) which is the ASTM standard. When a concrete worker walks on such wire grids during the pouring and layout process, the wire grid will deform in an undesirable manner.

In order to eliminate such deformation of a concrete reinforcing grid module which may easily connected to similar grid modules is needed which will bounce back or return to its original position after the load placed therein is removed. Therefore, there is a need for a concrete reinforcement product which will not deform when loaded with a person's weight, which is small enough to be carried by an individual and may be nestably stacked for storage purposes.

SUMMARY OF THE INVENTION

This invention comprises a nestably stackable concrete reinforcement grid module which is made of high tensile strength steel and may quickly and easily be connected to similar like grid modules.

The nestably stackable concrete reinforcement grid module comprises a plurality of spaced longitudinal wires extending longitudinally along the length of the concrete reinforcement grid module and a plurality of spaced transverse wires extending transversely along the width of the concrete reinforcement grid module, each transverse wire intersecting each of the spaced longitudinal wires of the grid module. The wires are preferably welded together at their intersections, but may be secured together is any desired manner.

In one embodiment, each of the transverse wires has a linear middle portion and tail portions at the ends of thereof for locking or securing together multiple grid modules. However, the transverse wires may assume other shapes or configurations. Similarly, some of the longitudinal wires have a linear middle portion and tail portions at the ends of thereof for locking together multiple grid modules while other longitudinal wires are generally corrugated along their lengths, having flattened peaks and flattened valleys joined by connectors. The flattened valleys of the longitudinal wires of the grid module rest on the ground or substrate for purposes of stabilizing the grid module, thereby eliminating any need for chairs or supports prior to pouring the concrete.

In at least some of the wires, tail or end portions extend downwardly from adjacent portions of the wire at an angle of 30-45 degrees relative to the adjacent portion of wire. The tail portions are used to interconnect or interlock multiple like grid modules together without the use of fasteners or tools of any sort.

In one embodiment, each of the wires is made of ten gauge high tensile strength wire which provides for additional pull strength preventing sections of the concrete from separating if cracked. Other gauge or diameter wires may be used if desired. The tensile strength of the wires is greater than 75,000 psi and preferably approximately 100,000 psi. Such high tensile wires allow the grid module to spring back or return to its original position if stepped on during the concrete forming process.

Any number of pre-welded grid modules of the present invention may be nestably stacked together into a stack and placed inside a cardboard collar. The collar may have assembly instructions or other indicia printed on the outside surface thereof for marketing purposes. Alternatively, any number of pre-welded grid modules of the present invention may be combined into a stack and the stack surrounded with a cardboard collar.

Plastic or metal collars may be then wrapped around the cardboard collar and stack of grid modules to create an attractive package for sale to a customer.

In operation, a person may open the package by cutting the collars and then removing one or more grid modules from the stack of grid modules. Multiple grid modules may be interlocked together inside a concrete form using the edge lock feature of the grid modules of the present invention before the concrete is poured.

The configuration of the pre-welded grid module of the present invention allows a user to easily and quickly assembly a concrete reinforcement grid of a desired size prior to pouring concrete in a pre-assembled form, as is known in the art.

These and other objects and advantages of the present invention will be more readily apparent from the following description of the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a package of nestably stacked concrete reinforcing grid modules constructed in accordance with the present invention;

FIG. 2 is a perspective view of a stack of packages like the package shown in FIG. 1;

FIG. 3A is a perspective view of a first concrete reinforcing grid module constructed in accordance with the present invention resting in a form and a second concrete reinforcing grid module being secured to the first concrete reinforcing grid module in the form;

FIG. 3B is a perspective view of the first and second concrete reinforcing grid modules of FIG. 3A secured together inside the form;

FIG. 4A is a view taken along the line 4A-4A of FIG. 3B;

FIG. 4B is an enlarged view of a portion of FIG. 4A;

FIG. 5A is a side elevational view partially in cross-section of a method of creating a stack of concrete reinforcing grid modules inside a collar; and

FIG. 5B is a side elevational view partially in cross-section of a package of concrete reinforcing grid modules constructed as shown in FIG. 5A.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring to the drawings, and particularly to FIG. 1, there is illustrated a package 10 including a stack 12 of identical concrete reinforcing grid modules 14 inside a generally rectangular cardboard collar 16 and two bands 18 surrounding the stack 12 of concrete reinforcing grid modules 14 and cardboard collar 16. Although two bands 18 are shown surrounding the stack 12 of concrete reinforcing grid modules 14 and collar 16, any number of bands may be used in any desired orientation or manner. The outside surface 19 of the cardboard collar 16 preferably has indicia 20 such as instructions and trademark material printed thereon. The present invention may be packaged in another manner using other materials if desired.

FIG. 2 illustrates a plurality of packages 10 as shown in FIG. 1 stacked on top of each other to create a bundle 22 of packages 10.

Referring to FIG. 3A, one embodiment of nestably stackable concrete reinforcing grid module 14 has a transverse dimension or width W, a longitudinal dimension or length L and a height H. See FIG. 4B. In one embodiment, the grid module is 34 inches wide, 46 inches long and two inches tall. These dimensions are preferable for using the grid modules in walk ways or patio floors which are either three or four feet wide because no cutting is necessary. However, any other size concrete reinforcement grid module made in accordance with the present invention may be used to make a grid for reinforcing concrete.

The nestably stackable concrete reinforcing grid module 14 comprises a plurality of transverse wires 24 extending in a transverse direction (from side-to-side), each having a straight or linear middle portion 26 and a pair of end or tail portions 28 at opposed ends of the transverse wire 24. Each tail portion 28 extends outwardly and downwardly at an angle of 30-45 degrees from the straight middle portion 26 of the transverse wire 24. However, other angles may be used if desired.

The nestably stackable concrete reinforcing grid module 14 further comprises a plurality of longitudinal wires 30 extending in a longitudinal direction or from end-to-end of the module 14. The outermost longitudinal wires 31 each have a straight or linear middle portion 32 and a pair of tail or end portions 34 at opposed ends of the longitudinal wire 31, like each of the transverse wires 24. Each tail portion 34 extends outwardly and downwardly at an angle of 30-45 degrees from the straight middle portion 32 of the outermost longitudinal wire 31. However, the tail portion 34 may extend downwardly from the middle portion 32 at any desired angle. Similarly, nestably stackable concrete reinforcing grid module 14 further comprises two internal longitudinal wires 36, each having a straight or linear middle portion 38 and a pair of tail or end portions 40 at opposed ends of the internal longitudinal wire 36. Each tail portion 40 extends outwardly and downwardly at an angle of 30-45 degrees from the straight middle portion 38 of the internal longitudinal wire 36. However, the tail portion 40 may extend downwardly from the middle portion 38 at any desired angle.

The nestably stackable concrete reinforcing grid module 14 further comprises a pair of longitudinal wires 42 extending in a longitudinal direction, each longitudinal wire 42 being located between one of the outermost longitudinal wires 31 and the internal longitudinal wires 36 and secured to each of the transverse wires 24. The longitudinal wires 42 each are generally corrugated along their length and have generally co-planar flattened peaks 44 and generally co-planar flattened valleys 46 joined together with connectors 48. Each longitudinal wire 42 has a pair of tail or end portions 50 at opposed ends of the generally corrugated longitudinal wire 42 adjacent and extending outwardly and downwardly at an angle of 30-45 degrees from one of the peaks 44 of the longitudinal wire 42. However, the tail portion 50 may extend downwardly from the one of the peaks 44 at any desired angle.

Although the figures show five transverse wires 24 and five longitudinal wires 30 including two generally corrugated longitudinal wires 42 in the nestably stackable concrete reinforcing grid module 14, any number of transverse or longitudinal wires may be incorporated into a nestably stackable concrete reinforcing grid module in accordance with the present invention. Similarly, although the figures show each wire having tail portions at each end thereof, tail portions may be omitted from one or more ends of one or more wires if desired.

As illustrated in FIGS. 3A and 3B, a first nestably stackable concrete reinforcing grid module 14a is placed on the ground or substrate 52 inside a wooden form 54. A second nestably stackable concrete reinforcing grid module 14b is placed on the ground or substrate 52 inside the wooden form 54 so that the tail portions of the longitudinal wires 30 of the second nestably stackable concrete reinforcing grid module 14b interlock with an outermost transverse wire 24a of the first nestably stackable concrete reinforcing grid module 14a, thereby connecting the first and second nestably stackable concrete reinforcing grid modules 14a, 14b inside the form 54. See FIG. 3B. As shown in FIG. 4B, the tail portions of the longitudinal wires 30 of the second nestably stackable concrete reinforcing grid module 14b lay over an outermost transverse wire 25 of the first nestably stackable concrete reinforcing grid module 14a, thereby joining the first and second nestably stackable concrete reinforcing grid modules 14a, 14b inside the form 54.

Although not shown, the tail portions 28 of the transverse wires 24 of any of the nestably stackable concrete reinforcing grid modules may interlock with an outermost longitudinal wire of an adjacent nestably stackable concrete reinforcing grid module, thereby connecting the adjacent nestably stackable concrete reinforcing grid modules in a side-by-side manner inside a form before the concrete is poured.

As shown in FIGS. 4A and 4B, at least a portion of the flattened valleys 46 of the generally corrugated longitudinal wires 42 of each grid module 14a, 14b rest on or are supported by the ground or substrate 52.

FIGS. 5A and 5B illustrate another method of making a package of concrete reinforcing grids in accordance with the present invention. Referring to FIG. 5A, a plurality of grid modules 14c are similarly aligned with the flattened valleys 46c of the grid modules 14c located above the flattened peaks (hidden in FIGS. 5A and 5B) and outermost longitudinal wires 31c of each of the grid modules 14c. Similarly, a plurality of grid modules 14d are similarly aligned with the flattened valleys 46d of the grid modules 14d located below the flattened peaks (hidden in FIGS. 5A and 5B) and outermost longitudinal wires 31d of each of the grid modules 14d. As depicted by arrows 56, the grid modules 14c are lowered and intermesh with the spaced grid modules 14d to form a stack 58. In the stack 58, every other grid module 14c is turned upside relative to those grid modules 14d adjacent to it. See FIG. 5B. This type of stacking arrangement creates a stack 58 having flattened surfaces which may be surrounded with a collar 16 and easily banded in a tight, efficient manner. See FIG. 1.

Although I have described one preferred embodiment of the invention, I do not intend to be limited except by the scope of the following claims.

Claims

1. A nestably stackable concrete reinforcing grid module comprising:

a plurality of spaced longitudinal wires, some of said longitudinal wires being generally corrugated along their lengths including flattened peaks and valleys;

a plurality of spaced transverse wires secured to said longitudinal wires at intersections;

wherein at least some of said wires have tail portions at the ends thereof for locking together multiple grid modules.

2. The concrete reinforcing grid module of claim 1, wherein said wires are made of high tensile strength steel.

3. The concrete reinforcing grid module of claim 1 wherein said tail portions are bent down relative to adjacent portions of each of said wires.

4. The concrete reinforcing grid module of claim 3 wherein said end portions are bent down 30-45 degrees relative to said adjacent portions of said wires.

5. The concrete reinforcing grid module of claim 1 wherein each of said transverse wires has a linear middle portion between the tail portions.

6. The concrete reinforcing grid module of claim 1 wherein said transverse wires are secured to said flattened peaks of said longitudinal wires.

7. The concrete reinforcing grid module of claim 1 wherein wires of said grid module have a tensile strength greater than 75,000 psi.

8. The concrete reinforcing grid module of claim 1 wherein each of said wires of said grid module have a tensile strength of approximately 100,000 psi.

9. The concrete reinforcing grid module of claim 1 wherein each of said wires of said grid module are welded together.

10. A nestably stackable concrete reinforcing grid module comprising:

a plurality of spaced longitudinal wires;

a plurality of spaced transverse wires welded to said longitudinal wires at intersections;

wherein at least some of said wires are made of high tensile strength wire having a tensile strength of greater than 75,000 psi.

11. The concrete reinforcing grid module of claim 10 wherein at least some of said wires have tail portions at the ends thereof for locking together multiple grid modules.

12. The concrete reinforcing grid module of claim 10 wherein at least some of said longitudinal wires are generally corrugated along their lengths and have flattened peaks and valleys.

13. The concrete reinforcing grid module of claim 12 wherein said transverse wires are welded to said flattened peaks of said longitudinal wires.

14. The concrete reinforcing grid module of claim 10 wherein all of said wires have a tensile strength of greater than 75,000 psi.

15. The concrete reinforcing grid module of claim 10 wherein all of said wires have tail portions at the ends thereof for locking together multiple grid modules.

16. A package of nestably stacked concrete reinforcing grid modules, said package comprising:

a stack of welded concrete reinforcing grid modules, each of said concrete reinforcing grid modules comprising:

spaced longitudinal wires;

a plurality of spaced transverse wires welded to said longitudinal wires at intersections;

wherein at least some of said wires have tail portions at the ends thereof for locking together multiple grid modules; and

a collar surrounding said stack of welded concrete reinforcing grid modules.

17. The package of claim 16 further comprising collars surrounding said stack of welded concrete reinforcing grid modules and said collar.

18. The package of claim 16 wherein said collar is made of cardboard and has information printed thereon.

19. The package of claim 16 wherein each of said concrete reinforcing grid modules is made of wire having a tensile strength greater than 75,000 psi.

20. The package of claim 16 wherein each of said concrete reinforcing grid modules is made of wire having a tensile strength of approximately 100,000 psi.

21. A method of making a concrete reinforcing grid comprising:

providing first and second nestably stackable concrete reinforcing grid modules, each of said modules comprising:

a plurality of spaced longitudinal wires, some of said longitudinal wires being generally corrugated along their lengths including flattened peaks and valleys;

a plurality of spaced transverse wires secured to said longitudinal wires at intersections;

wherein at least some of said wires have tail portions at the ends thereof for locking together multiple grid modules;

placing said first grid module on a substrate such that said flattened valleys of said first grid module contact the substrate;

placing said second grid module on the substrate such that said flattened valleys of said second grid module contact the substrate and said tail portions of said second grid module overlie an outermost wire of said first grid module.