US20230399801A1

US20230399801A1 - Concrete slab load transfer and connection apparatus

Info

Publication number: US20230399801A1
Application number: US18/332,384
Authority: US
Inventors: Darrell A. Wiatrowski; Christopher J. Nelli
Original assignee: Illinois Tool Works Inc
Current assignee: Illinois Tool Works Inc
Priority date: 2022-06-14
Filing date: 2023-06-09
Publication date: 2023-12-14
Also published as: AU2023203665A1

Abstract

Various embodiments of the present disclosure provide a cast-in-place concrete slab load transfer and slab connection apparatus and method of employing same.

Description

PRIORITY CLAIM

This application claims priority to and the benefit of U.S. Provisional Patent Application Ser. No. 63/410,479, filed Sep. 27, 2022, and U.S. Provisional Patent Application Ser. No. 63/352,003, filed Jun. 14, 2022, the entire contents of each of which are incorporated herein by reference.

BACKGROUND

Various concrete floors and roadways include a series of separate individually poured or cast-in-place concrete slabs that are referred to herein as “concrete slabs.” Various known issues with such concrete slabs relate to the joint between adjacent concrete slabs, the relative movements of adjacent concrete slabs when loads are placed on the concrete slabs, and the opening that forms between adjacent concrete slabs at the joint.
Two types of joints are often used for concrete slabs. Construction joints are often used between separately individually poured adjacent concrete slabs that are poured at sequential times. Contraction joints (which are sometimes called control joints) are often used for simultaneously poured adjacent concrete slabs. Contraction joints are often partially formed by vertically cutting a larger concrete slab at a desired location of the contraction joint to form the separate adjacent concrete slabs. The vertical cut often extends approximately one third of the way through the depth of the concrete. When the larger concrete slab cracks along the cut, the respective concrete slabs are able to separate. Contraction joints are thus often used to control natural cracking in concrete slabs from stresses caused by concrete shrinkage, thermal contraction, moisture, or thermal gradients within the concrete, and/or various external forces on the concrete slabs.
Freshly poured concrete shrinks as it cures and hardens due to the chemical reaction that occurs between the cement and water. As the concrete shrinks, stress can accumulate in the concrete. Therefore, the joint between two adjacent concrete slabs needs to be able to open to enable such shrinkage of each of the individual concrete slabs without damaging the concrete slabs and while maintaining the integrity of the joint.
After curing and hardening, adjacent concrete slabs are also subject to loads that can cause the movements of the concrete slabs relative to one another. Various construction and contraction joints include load transferring dowels of various different geometries that connect adjacent concrete slabs such that the movement of one concrete slab causes the movement of the adjacent concrete slab. In other words, these load transferring dowels connect the adjacent concrete slabs such that they substantially move together when a load is placed on one of the adjacent concrete slabs.
Certain known concrete slab load transfer and connection apparatus used in forming contraction joints include a basket that holds a plurality of spaced apart flat dowels. In certain cases, after manufacture, during storage, shipping, or installation, the flat dowels can become mis-aligned within the basket or dislodged from the basket (and in certain instances lost). When this occurs, additional time must be spent re-aligning or locating, obtaining, and reinserting the flat dowels in the basket prior to usage of the apparatus.
There is a continuing need to develop new and better concrete slab load transfer and connection apparatus for forming joints between adjacent concrete slabs.

SUMMARY

Various embodiments of the present disclosure provide concrete slab load transfer and connection apparatuses for concrete slabs of floors and roadways that includes a basket that more securely holds in proper alignment the flat dowels and addresses the above issue. Various embodiments of the present disclosure also provide a method of forming the concrete slab load transfer and connection apparatuses. Various embodiments of the present disclosure further provide a method of using the concrete slab load transfer and connection apparatuses for concrete slabs of floors and roadways.
Additional features and advantages of the present invention are described in, and will be apparent from, the following Detailed Description and the Figures.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a top perspective view of the concrete slab load transfer and connection apparatus of one example embodiment of the present disclosure.

FIG. 2 is a top view of the concrete slab load transfer and connection apparatus of FIG. 1 .

FIG. 3 is a side view of the concrete slab load transfer and connection apparatus of FIG. 1 .

FIG. 4 is an end view of the concrete slab load transfer and connection apparatus of FIG. 1 .

FIG. 5 is a top perspective view of the concrete slab load transfer and connection apparatus of FIG. 1 positioned on a substrate for forming a roadway.

FIG. 6 is a fragmentary top perspective view of the concrete slab load transfer and connection apparatus of another example embodiment of the present disclosure.

FIG. 7 is a first fragmentary top view of the concrete slab load transfer and connection apparatus of FIG. 6 .

FIG. 8 is a second fragmentary top view of the concrete slab load transfer and connection apparatus of FIG. 6 .

FIG. 9 is a fragmentary top view of the concrete slab load transfer and connection apparatus of another example embodiment of the present disclosure.

FIG. 10 is a fragmentary top perspective view of the concrete slab load transfer and connection apparatus of another example embodiment of the present disclosure.

FIG. 11 is a fragmentary top view of the concrete slab load transfer and connection apparatus of FIG. 10 .

FIG. 12 is a top fragmentary view of the load transfer plate, one of the side walls, and one of the hands of the concrete slab load transfer and connection apparatus of FIG. 10 .

FIG. 13 is a top view of the load transfer plate of the concrete slab load transfer and connection apparatus of FIG. 10 .

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

While the features, devices, and apparatus described herein may be embodied in various forms, the drawings show, and the specification describe certain exemplary and non-limiting embodiments. Not all of the components shown in the drawings and described in the specification may be required, and certain implementations may include additional, different, or fewer components. Variations in the arrangement and type of the components; the shapes, sizes, and materials of the components; and the manners of connections of the components may be made without departing from the spirit or scope of the claims. Unless otherwise indicated, any directions referred to in the specification reflect the orientations of the components shown in the corresponding drawings and do not limit the scope of the present disclosure. Further, terms that refer to mounting methods, such as mounted, attached, connected, and the like, are not intended to be limited to direct mounting methods but should be interpreted broadly to include indirect and operably mounted, attached, connected and like mounting methods. This specification is intended to be taken as a whole and interpreted in accordance with the principles of the present disclosure and as understood by one of ordinary skill in the art.
Various embodiments of the present disclosure provide a concrete slab load transfer and connection apparatus. For brevity, and without limiting the present disclosure, the concrete slab load transfer and connection apparatus may sometimes be referred to herein as the “transfer and connection apparatus” or as the “apparatus.”
FIGS. 1, 2, 3, 4, and 5 illustrate the concrete slab load transfer and connection apparatus of one example embodiment of the present disclosure, and which is generally indicated by numeral 100.
The concrete slab load transfer and connection apparatus 100 includes a basket 110 and a plurality of spaced apart load transfer dowels 150 a, 150 b, and 150 c securely connected to and supported by the basket 100.
The basket 110 includes a first side frame 112, a second side frame 122 spaced-apart from the first side frame 112, and a plurality of side frame connectors such as side frame connectors 180 a and 180 b.
The first side frame 112 includes a first lower elongated member 114 and a first upper elongated member 116 above and spaced-apart from the first lower elongated member 114. The first side frame 112 further includes dowel holding hands 120 a, 120 b, and 120 c respectively connected to members 114 and 116 and additionally connecting member 114 and 116. The dowel holding hands 120 a, 120 b, and 120 c are shaped and connected to the first upper elongated member 116 such that they define dowel receipt openings (not labeled) above the elongated member 116 that are configured to receive end sections of the dowels 150 a, 150 b, and 150 c. In various embodiments, each of the hands includes a suitable hook for engagement with the respective dowel.
Likewise, the second side frame 122 includes a second lower elongated member 124 and a second upper elongated member 126 above and spaced apart from the second lower elongated member 124. The second side frame 122 further includes dowel holding hands 130 a, 130 b, and 130 c respectively connected to members 124 and 126 and connecting members 124 and 126. The dowel holding hands 130 a, 130 b, and 130 c are shaped and connected to the second upper elongated member 126 such that they define dowel receipt openings (not labeled) above the elongated member 126 that are configured to receive end sections of the dowels 150 a, 150 b, and 150 c.
The side frame connectors 180 a and 180 b are each connected at a first end thereof to the first upper elongated member 116 and at a second end thereof to the second upper elongated member 126. The side frame connectors 180 a and 180 b are connected to the side frames 112 and 122 in a manner such that they are able to break from one or both of the side frames 112 and 122 when the concrete slabs in which the apparatus 100 is embedded move apart from each other. In particular, after the first side frame 112 is embedded in a first concrete slab and the second side frame 122 is embedded in an adjacent concrete slab, when these concrete slabs move apart, the side frame connectors 180 a and 180 b are configured to break off from one or both of the side frames 112 and 122 thereby enabling the side frames 112 and 122 to move apart from each other. In certain situations, the side frame connectors 180 a and/or 180 b can alternatively break when this occurs.
The first and second side frames 112 and 122 are configured to co-act to securely hold and support a plurality of load transfer members and particularly the load transfer dowels or dowels 150 a, 150 b, and 150 c at or along an area where a transversely extending contraction joint will extend between adjacent concrete slabs such as generally shown by the dotted line in FIG. 5 .
In this illustrated embodiment, each load transfer dowel 150 a, 150 b, and 150 c is of an elongated hexagonal shape with flat opposite ends (not labeled). More specifically, each dowel has a center section (not labeled), a first end section (not labeled), and a second end section (not labeled), a top planar surface (not labeled), and a bottom planar surface (not labeled). The center section is wider than each of the first and second end sections. The load transfer dowel tapers inwardly from the widest point of the center section in opposing directions to the respective narrowest points of the respective first and second end sections. In this illustrated example embodiment, the center section has the widest width of approximately 3 inches (7.62 cms), the first and second sections have the narrowest width of approximately 1 inches (2.54 cms), and the length of each bad transfer dowel is approximately 12 inches (30.48 cms). The top and bottom surfaces are substantially flat and substantially parallel to one another in this illustrated example embodiment. The functionality provided by certain load transfer dowels are described in U.S. Pat. Nos. 7,716,890, 7,481,031, and 8,381,470.
In this illustrated embodiment, the basket 110 and the load transfer dowels 150 a, 150 b, and 150 c are steel. More specifically, in this illustrated example embodiment, the first lower elongated member 114, the first upper elongated member 116, the dowel holding hands 120 a, 120 b, and 120 c, the second lower elongated member 124, the second upper elongated member 126 spaced apart from the second lower elongated member 124, the dowel holding hands 130 a, 130 b, and 130 c, and the side frame connectors 180 a and 180 b are each made from generally cylindrical steel rods but can be otherwise suitably formed. In this example, these components are connected by welds. In this illustrated example embodiment, the load transfer dowels 150 a, 150 b, and 150 c are each flat steel plates. It should be appreciated that one or more of these components can be made from other suitable materials in accordance with the present disclosure. It should also be appreciated that one or more of the basket and the plurality of load transfer dowels can be made in other suitable sizes, shapes, and configurations in accordance with the present disclosure.
The load transfer dowels 150 a, 150 b, and 150 c are supported by the first side frame 112 and the second side frame 122 of the basket 110, More specifically, in this illustrated example embodiment: (a) a first end of the load transfer dowel 150 a is supported and held in place by the first upper elongated member 116 and the dowel holding hand 120 a; (b) the second end of the load transfer dowel 150 a is supported and held in place by the upper elongated member 126 and the dowel holding hand 130 a; (c) a first end of the load transfer dowel 150 b is supported and held in place by the first upper elongated member 116 and the dowel holding hand 120 b; (d) the second end of the load transfer dowel 150 b is supported and held in place by the upper elongated member 126 and the dowel holding hand 130 b; (e) a first end of the load transfer dowel 150 c is supported and held in place by the first upper elongated member 116 and the dowel holding hand 120 c; and (f) the second end of the load transfer dowel 150 c is supported and held in place by the upper elongated member 126 and the dowel holding hand 130 c. The basket 110 and the load transfer dowels 150 a, 150 b, and 150 c are configured, arranged, and connected such that the load transfer dowels 150 a, 150 b, and 150 c apply outward tension to both the first and second upper elongated members 116 and 126 of the side frames 112 and 122 of the basket 100 and those members securely maintain in proper alignment the load transfer dowels 150 a, 150 b, and 150 c attached to the basket 110 after manufacture, during storage, during transport, and during installation.
More specifically, the dowels 150 a, 150 b, and 150 c, the dowel holding hands 120 a, 120 b, and 120 c, and the dowel holding hands 130 a, 130 b, and 130 c are each sized, shaped, and otherwise configured such that when the dowels 150 a, 150 b, and 150 c are positioned in the dowel receipt openings (defined by the dowel holding hands 120 a, 120 b, and 120 c and the first upper elongated member 116) and the dowel receipt openings (defined by the dowel holding hands 130 a, 130 b, and 130 c and the second upper elongated member 126), the dowels 150 a, 150 b, and 150 c apply outward tension to first and second upper elongated members 116 and 126. The first and second upper elongated members 116 and 126 are biased inwardly toward their natural positions and thus operate with the dowel holding hands 120 a, 120 b, and 120 c and the dowel holding hands 130 a, 130 b, and 130 c to apply pressure on opposite end sections of the dowels 150 a, 150 b, and 150 c to maintain the dowels 150 a, 150 b, and 150 c securely attached to the basket 110 after manufacture and during storage, shipping, and installation. This tension causes a plurality of spaced apart first sections of the first upper elongated member 116 and a plurality of spaced apart second sections of the second upper elongated member 126 that are transversely aligned with the respective dowels 150 a, 150 b, and 150 c to be outwardly biased, curved, or convex, as best shown in FIG. 2 .
In various embodiments, during the manufacturing method, after the basket 110 is formed, and prior to attachment of the dowels 150 a, 150 b, and 150 c to the basket 110, the first upper elongated member 116 and the second upper elongated member 126 are both straight (or substantially straight) and are both parallel (or substantially parallel) to each other. To attach the dowels 150 a, 150 b and 150 c to the basket 110, the first upper elongated member 116 and/or the second upper elongated member 126 are biased outwardly to enable the respective ends of the dowels 150 a, 150 b and 150 c to be inserted into the respective dowel receipt openings of the opposite side frames 112 and 122.
In various other embodiments, during the manufacturing method, after the first side frame 112 and the second side frame 122 are formed but before they are attached by the side frame connectors 180 a and 180 b, the dowels 150 a, 150 b, and 150 c are inserted into the respective dowel receipt openings of the opposite side frames 112 and 122. At this point, the first upper elongated member 116 and the second upper elongated member 126 are both straight (or substantially straight). Thereafter, the side frame connectors 180 a and 180 b are connected to the upper member 116 and 126 of the side frames 112 and 122. This connection process includes outwardly bending the first upper elongated member 116 and/or the second upper elongated member 126 before attaching the side frame connectors 180 a and 180 b to the first upper elongated member 116 and the second upper elongated member 126. As further explained below, this connection process could alternatively include inwardly bending the first upper elongated member 116 and/or the second upper elongated member 126 to attach the side frame connectors 180 a and 180 b to the first upper elongated member 116 and the second upper elongated member 126.
The concrete slab load transfer and connection apparatus 100 is configured to be used or positioned such that the load transfer dowels 150 a, 150 b, and 150 c of the apparatus 100 are positioned for load transfer at areas where contraction joints will be formed between pairs of adjacent concrete slabs such as shown in FIG. 5 . After positioning the apparatus 100, after pouring the concrete, after saw cutting the contraction joints, and after the contraction joints have formed, the load transfer dowels 150 a, 150 b, and 150 c of the apparatus 100 operate to transfer loads between adjacent concrete slabs. More specifically, the present disclosure provides a method of or for forming a section of a roadway or floor employing a plurality of concrete slab load transfer and connection apparatus 100. In various such embodiments, the method includes positioning the apparatus 100 on a grade or sub-surface to form part of a section of a roadway or floor such that the load transfer dowels 150 a, 150 b, and 150 c of that apparatus 100 are positioned for load transfer at the area where a contraction joint will be formed between a pair of longitudinally adjacent concrete slabs of the roadway or floor. The method further includes subsequently pouring the concrete to form the section of the roadway or floor. The method subsequently includes allowing the poured concrete of the section of the roadway or floor to partially or fully set or cure. After the partial or full setting or curing of the concrete, the method includes saw cutting the transversely extending contraction joint in the sections of the roadway or floor along the appropriate line based on the positions of each of the apparatus 100. The method includes the concrete slabs separating or moving apart from each other thereby causing the connection members 180 a and 180 b to break or to break from the side frames 112 and 122 and allowing the respective spaced apart side frames 112 and 122 to move apart from each other in the respective concrete slabs. When this occurs, the tension between the load transfer dowels 150 a, 150 b, and 150 c and the members 116 and 126 of the basket 110 is relieved, reduced, or eliminated such that each of the load transfer dowels 150 a, 150 b, and 150 c are moveable in one of the concrete slabs and is thus positioned to provide its load transfer functionality for the concrete slabs.
FIGS. 6, 7, and 8 illustrate the concrete slab load transfer and connection apparatus of another example embodiment of the present disclosure, and which is generally indicated by numeral 200.
The concrete slab load transfer and connection apparatus 200 includes a basket 210 and a plurality of spaced apart load transfer dowels 250 a, 250 b, and 250 c securely connected to and supported by the basket 200.
The basket 210 includes a first side frame 212, a second side frame 222 spaced-apart from the first side frame 212, and a plurality of side frame connectors such as side frame connectors 280 a, 280 b, 280 c, and 280 d.
The first side frame 212 includes a first lower elongated member 214 and a first upper elongated member 216 spaced-apart from the first lower elongated member 214. The first side frame 212 further includes dowel holding hands 220 a, 220 b, and 220 c respectively connected to members 214 and 216. The dowel holding hands 220 a, 220 b, and 220 c are attached to the first upper elongated member 216 such that they define dowel receipt openings (not labeled) above the elongated member 216 that are configured to receive end sections of the dowels 250 a, 250 b, and 250 c.
Likewise, the second side frame 222 includes a second lower elongated member 224 and a second upper elongated member 226 spaced apart from the second lower elongated member 224. The second side frame 222 further includes dowel holding hands 230 a, 230 b, and 230 c respectively connected to members 224 and 226. The dowel holding hands 230 a, 230 b, and 230 c are attached to the second upper elongated member 226 such that they define dowel receipt openings (not labeled) above the elongated member 226 that are configured to receive end sections of the dowels 250 a, 250 b, and 250 c.
The side frame connectors 280 a, 280 b, 280 c, and 280 d are each connected adjacent a first end thereof to the first upper elongated member 216 and adjacent a second end thereof to the second upper elongated member 226. The side frame connectors 280 a, 280 b, 280 c, and 280 d are connected to the side frames 212 and 222 in a manner such that they are able to break from one or both of the side frames 212 and 222 when the concrete slabs in which the apparatus 200 is embedded move apart from each other. In this example embodiment, the side frame connectors 280 a, 280 b, 280 c, and 280 d are longer than side frame connectors 180 a and 180 b to accommodate assembly tolerances and for each of welding.
The first and second side frames 212 and 222 are configured to co-act to securely hold and support a plurality of load transfer members and particularly the load transfer dowels or dowels 250 a, 250 b, and 250 c at or along an area where a transversely extending contraction joint will extend between adjacent concrete slabs.
In this illustrated embodiment, each load transfer dowel 250 a, 250 b, and 250 c an elongated hexagonal shape with flat opposite ends (not labeled). In this illustrated embodiment, each load transfer dowel 250 a, 250 b, and 250 c is longer than the load transfer dowels 150 a, 150 b, and 150 c. More specifically, each dowel has a center section (not labeled), a first end section (not labeled), and a second end section (not labeled), a top planar surface (not labeled), and a bottom planar surface (not labeled). The center section is wider than each of the first and second end sections. The load transfer dowel tapers inwardly from the widest point of the center section in opposing directions to the respective narrowest points of the respective first and second end sections. In this illustrated example embodiment, the center section has the widest width of approximately 3 inches (7.62 cms), the first and second sections have the narrowest width of approximately 1 inches (2.54 cms), and the length of each bad transfer dowel is approximately 12 inches (30.48 cms). The top and bottom surfaces are substantially flat and substantially parallel to one another in this illustrated example embodiment.
In this illustrated embodiment, the basket 210 and the load transfer dowels 250 a, 250 b, and 250 c are steel. More specifically, in this illustrated example embodiment, the first lower elongated member 214, the first upper elongated member 216, the dowel holding hands 220 a, 220 b, and 220 c, the second lower elongated member 224, the second upper elongated member 226 spaced apart from the second lower elongated member 224, the dowel holding hands 230 a, 230 b, and 230 c, and the side frame connectors 280 a, 280 b, 280 c, and 280 d are each made from generally cylindrical steel rods, but can be otherwise suitably formed. In this embodiment, these components are connected by welds. In this illustrated example embodiment, the load transfer dowels 250 a, 250 b, and 250 c are each flat steel plates. It should be appreciated that one or more of these components can be made from other suitable materials in accordance with the present disclosure. It should also be appreciated that one or more of the basket and the plurality of load transfer dowels can be made in other suitable sizes, shapes, and configurations in accordance with the present disclosure.
The load transfer dowels 250 a, 250 b, and 250 c are supported by the first side frame 212 and the second side frame 222 of the basket 210. More specifically, in this illustrated example embodiment: (a) a first end of the load transfer dowel 250 a is supported and held in place by the first upper elongated member 216 and the dowel holding hand 220 a; (b) the second end of the load transfer dowel 250 a is supported and held in place by the upper elongated member 226 and the dowel holding hand 230 a; (c) a first end of the load transfer dowel 250 b is supported and held in place by the first upper elongated member 216 and the dowel holding hand 220 b; (d) the second end of the load transfer dowel 250 b is supported and held in place by the upper elongated member 226 and the dowel holding hand 230 b; (e) a first end of the load transfer dowel 250 c is supported and held in place by the first upper elongated member 216 and the dowel holding hand 220 c; and (f) the second end of the bad transfer dowel 250 c is supported and held in place by the upper elongated member 126 and the dowel holding hand 230 c.
The basket 210 and the load transfer dowels 250 a, 250 b, and 250 c are configured, arranged, and connected such that the load transfer dowels 250 a, 250 b, and 250 c apply outward tension to both the first and second upper elongated members 216 and 226 of the side frames 212 and 222 of the basket 200 and those members securely maintain the load transfer dowels 250 a, 250 b, and 250 c attached to the basket 210 after manufacture, during storage, during transport, and during installation.
More specifically, the dowels 250 a, 250 b, and 250 c, the dowel holding hands 220 a, 220 b, and 220 c, and the dowel holding hands 230 a, 230 b, and 230 c are each sized, shaped, and otherwise configured such that when the dowels 250 a, 250 b, and 250 c are positioned in the dowel receipt openings (defined by the dowel holding hands 220 a, 220 b, and 220 c and the first upper elongated member 216) and the dowel receipt openings (defined by the dowel holding hands 230 a, 230 b, and 230 c and the second upper elongated member 226), the dowels 250 a, 250 b, and 250 c apply outward tension to first and second upper elongated members 216 and 226. The first and second upper elongated members 216 and 26 are biased inwardly away from their natural positions and thus operate with the dowel holding hands 220 a, 220 b, and 220 c and the dowel holding hands 230 a, 230 b, and 230 c to apply pressure on opposite end sections of the dowels 250 a, 250 b, and 250 c to maintain the dowels 250 a, 250 b, and 250 c securely attached to the basket 210 after manufacture and during storage, shipping, and installation. This tension causes a plurality of spaced apart first sections of the first upper elongated member 216 and a plurality of spaced apart second sections of the second upper elongated member 226 that are adjacent to or between the respective dowels 250 a, 250 b, and 250 c to be inwardly biased, curved or concave as best shown in FIGS. 7 and 8 . FIG. 7 also shows the positions of the first and second upper elongated members 216 and 226 before the side frame connectors 280 a, 280 b, 280 c, and 280 d are connected to the first and second upper elongated members 216 and 226. Specifically, the positions of the first and second upper elongated members 216 and 226 before the side frame connectors 280 a, 280 b, 280 c, and 280 d are connected thereto are indicated by the cross-hatched sections 216X and 226X.
Thus, in this embodiment, during the manufacturing method, after the first side frame 212 and the second side frame 222 are formed but before they are attached by the side frame connectors 280 a, 280 b, 280 c, and 280 d, the dowels 250 a, 250 b, and 250 c are inserted into the respective dowel receipt openings of the opposite side frames 212 and 222. At this point, the first upper elongated member 216 and the second upper elongated member 226 are both straight (or substantially straight). Thereafter, the side frame connectors 280 a, 280 b, 280 c, and 280 d are connected to the upper member 216 and 226 of the side frames 212 and 222. This connection process includes inwardly bending the first upper elongated member 216 and/or the second upper elongated member 226 before attaching the side frame connectors 280 a, 280 b, 280 c, and 280 d to the first upper elongated member 216 and the second upper elongated member 226.
FIG. 9 illustrates the concrete slab load transfer and connection apparatus of another example embodiment of the present disclosure, and which is generally indicated by numeral 300. This embodiment is provided to show that the length of the concrete slab load transfer and connection apparatus and the quantity of dowels can vary in accordance with the present disclosure.
It should be appreciated from the above the elongated wire members undergo somewhat of an elastic deformation to apply tension to the dowels. In various embodiments, if the dowels were removed, such member would return to their original shape or natural positions. In certain instances, such member can be elastically deformed depending on the various dimensions of the components.
It should be appreciated from the above the inward and outward bending can relate to the assembly process and specifically whether the elongated members of the respective legs are attached before or after the dowels are attached.
In various embodiments of the present disclosure, the concrete slab load transfer and connection apparatus includes one or more dowel alignment mechanisms for each dowel. These dowel alignment mechanisms can include, for example, one or more alignment notches defined in the dowel and for one or both of the respective holding hands for such dowel an alignment finger extending into such alignment notch in that dowel. In such embodiments, each alignment finger extends into a respective one of the alignment notches for assuring proper alignment of the dowel. These mechanisms can also be configured for better securing the dowel to the basket.
For example, FIGS. 10, 11, 12, and 13 illustrate the concrete slab load transfer and connection apparatus of another example embodiment of the present disclosure, and which is generally indicated by numeral 300.
The concrete slab load transfer and connection apparatus 300 includes a basket 310 and a plurality of spaced apart load transfer dowels such as dowels 350 a and 350 b securely connected to and supported by the basket 310.
The basket 310 includes a first side frame 312, a second side frame 322 spaced-apart from the first side frame 312, and a plurality of side frame connectors such as side frame connectors 380 a and 380 b.
The first side frame 312 includes a first lower elongated member 314 and a first upper elongated member 316 spaced-apart from the first lower elongated member 314. The first side frame 312 further includes dowel holding hands such as hands 320 a and 320 b respectively connected to members 314 and 316. The dowel holding hands 320 a and 320 b are attached to the first upper elongated member 316 such that they define dowel receipt openings (not labeled) above the elongated member 316 that are configured to receive end sections of the dowels 350 a and 350 b. The dowel holding hands 320 a and 330 a respectively include upwardly extending alignment fingers 321 a and 331 a configured to be extend into opposing alignment notches 355 a and 356 a in the dowel 350 a as further described below.
Likewise, the second side frame 322 includes a second lower elongated member 324 and a second upper elongated member 326 spaced apart from the second lower elongated member 324. The second side frame 322 further includes dowel holding hands such as hands 330 a and 330 b respectively connected to members 324 and 326. The dowel holding hands 330 a and 330 b are attached to the second upper elongated member 326 such that they define dowel receipt openings (not labeled) above the elongated member 326 that are configured to receive end sections of the dowels 350 a and 350 b. The dowel holding hands 320 b and 330 b respectively include upwardly extending alignment fingers 321 b and 331 b configured to be extend into opposing alignment notches (not labeled) in the dowel 350 b.
The side frame connectors 380 a and 380 b are each connected adjacent a first end thereof to the first upper elongated member 316 and adjacent a second end thereof to the second upper elongated member 326. The side frame connectors 380 a and 380 b are connected to the side frames 312 and 322 in a manner such that they are able to break from one or both of the side frames 312 and 322 when the concrete slabs in which the apparatus 300 is embedded move apart from each other. In this example embodiment, the side frame connectors 380 a and 380 b are longer than side frame connectors 180 a and 180 b to accommodate assembly tolerances and for each of welding.
The first and second side frames 312 and 322 are configured to co-act to securely hold and support a plurality of load transfer members and particularly the load transfer dowels or dowels such as dowels 350 a and 350 b at or along an area where a transversely extending contraction joint will extend between adjacent concrete slabs.
In this illustrated embodiment, each load transfer dowel 350 a and 350 b has an elongated hexagonal shape. In this illustrated embodiment, each load transfer dowel 350 a and 350 b is longer than the load transfer dowels 150 a and 150 b. In this embodiment, each of the load transfer dowels are identical or substantially identical. Thus, for brevity, only load transfer dowel 350 a is described in more detail herein. Load transfer dowel 350 a includes a center section 352 a, a first end section 354 a, a second end section 366 a, a top planar surface 360 a, and a bottom planar surface 362 a. The center section 352 a is wider than each of the first and second end sections 354 a and 356 b. The load transfer dowel tapers inwardly from the widest point of the center section 352 a in opposing directions to the respective narrowest points of the respective first and second end sections 354 a and 356 a. In this illustrated example embodiment, the center section 354 a has the widest width of approximately 3 inches (7.62 cms), the first and second sections 354 a and 356 a have the narrowest width of approximately 1 inches (2.54 cms), and the length of the bad transfer dowel 350 a is approximately 12 inches (30.48 cms). The top and bottom surfaces are substantially flat and substantially parallel to one another in this illustrated example embodiment. The first and second end sections 354 a and 356 b respectively define alignment notches or finger receiving slots 355 a and 357 a (as best shown in FIG. 13 ) configured to receive the respective alignment fingers 321 a and 331 a of the hands 320 a and 330 a. The combination of the alignment fingers 321 a and 331 positioned in the alignment notches 355 a and 357 a provide for the alignment of the dowel 350 a with the first and second side frames 312 and 322. The combination of the alignment fingers 321 a and 331 a positioned in the alignment notches 355 a and 357 a enable the first and second side frames 312 and 322 to better secure the dowel 350 a in the basket 310. It should be appreciated that the sizes, shapes, and/or locations of the alignment notched can vary in accordance with the present disclosure. Likewise, it should be appreciated that the sizes, shapes, and/or locations of the alignment fingers can vary in accordance with the present disclosure.
In a similar manner, the combination of the alignment fingers 321 b and 331 b positioned in the alignment notches (not labeled) provide for the alignment of the dowel 350 b with the first and second side frames 312 and 322 and better secure the dowel 350 b in the basket 310.
In this illustrated embodiment, the basket 310 and the load transfer dowels 350 a and 350 b are steel. More specifically, in this illustrated example embodiment, the first lower elongated member 314, the first upper elongated member 316, the dowel holding hands 320 a and 320 b, the second lower elongated member 324, the second upper elongated member 326, the dowel holding hands 330 a and 330 b, and the side frame connectors 380 a and 380 b are each made from generally cylindrical steel rods but can be otherwise suitably formed. In this embodiment, these components are connected by welds. In this illustrated example embodiment, the load transfer dowels 350 a and 350 b are each flat steel plates. It should be appreciated that one or more of these components can be made from other suitable materials in accordance with the present disclosure. It should also be appreciated that one or more of the basket and the plurality of load transfer dowels can be made in other suitable sizes, shapes, and configurations in accordance with the present disclosure.
The load transfer dowels 350 a and 350 b are supported by the first side frame 312 and the second side frame 322 of the basket 310. More specifically, in this illustrated example embodiment: (a) a first end of the load transfer dowel 350 a is supported and held in place by the first upper elongated member 316 and the dowel holding hand 320 a; (b) the second end of the load transfer dowel 350 a is supported and held in place by the upper elongated member 326 and the dowel holding hand 330 a; (C) a first end of the load transfer dowel 350 b is supported and held in place by the first upper elongated member 316 and the dowel holding hand 320 b; and (d) the second end of the load transfer dowel 350 b is supported and held in place by the upper elongated member 326 and the dowel holding hand 330 b.
Additionally, as with the above described embodiment, the basket 310 and the load transfer dowels 350 a and 350 b can be configured, arranged, and connected such that the bad transfer dowels 350 a and 350 b apply outward tension to both the first and second upper elongated members 316 and 326 of the side frames 312 and 322 of the basket 310 to maintain the load transfer dowels 350 a and 350 b attached to the basket 310 after manufacture, during storage, during transport, and during installation.
Additionally, as with the above-described embodiment, the basket 310 and the load transfer dowels 350 a and 350 b can be configured, arranged, and connected such that the first and second upper elongated members 316 and 326 apply inward tension to the bad transfer dowels 350 a and 350 b to maintain the load transfer dowels 350 a and 350 b attached to the basket 310 after manufacture, during storage, during transport, and during installation.
It should be appreciated from the above that various embodiments of the present disclosure provide a concrete slab load transfer and connection apparatus comprising: a plurality of load transfer dowels; and a basket supporting the load transfer dowels, the basket including: (1) a first side frame including a first lower elongated member, a first upper elongated member, a plurality of first dowel holding hands connected to the first lower elongated member and the first upper elongated member, (2) a second side frame including a second lower elongated member, a second upper elongated member, a plurality of second dowel holding hands connected to the second lower elongated member and the second upper elongated member, and (3) a plurality of side frame connectors connecting the first side frame and the second side frame, wherein a plurality of first sections of the first upper elongated member and a plurality of second sections of the second upper elongated member are biased against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.
In various such embodiments, the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member are biased outwardly against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.
In various such embodiments, the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member are aligned with the load transfer dowels.
In various such embodiments, one of the holding hands for each dowel includes an alignment finger extending into an alignment notch for that dowel.
In various such embodiments, the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member are biased inwardly against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.
In various such embodiments, the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member are between the load transfer dowels.
In various such embodiments, one of the holding hands for each dowel includes an alignment finger extending into an alignment notch for that dowel.
In various such embodiments, one of the holding hands for each dowel includes an alignment finger extending into an alignment notch for that dowel.
In various such embodiments, each dowel defines opposing alignment notches, and each holding hand includes an alignment finger that extends into one of the alignment notches of one of the dowels.
It should be further appreciated from the above that various embodiments of the present disclosure provide a method of forming a concrete slab load transfer and connection apparatus, wherein the method comprises: (1) forming a first side frame of a basket including a first lower elongated member, a first upper elongated member, a plurality of first dowel holding hands connected to the first lower elongated member and the first upper elongated member; (2) forming a second side frame of the basket including a second lower elongated member, a second upper elongated member, a plurality of second dowel holding hands connected to the second lower elongated member and the second upper elongated member; (3) connecting a plurality of dowels to the first upper elongated member and the first dowel holding hands; (4) connecting the plurality of dowels to the second upper elongated member and the second dowel holding hands; and (5) connecting a plurality of side frame connectors to the first side frame and the second side frame, such that a plurality of first sections of the first upper elongated member and a plurality of second sections of the second upper elongated member are biased against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.
In various such embodiments, the method includes causing the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member to be biased outwardly against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.
In various such embodiments, the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member are aligned with the load transfer dowels.
In various such embodiments, the method includes causing the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member to be biased inwardly against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.
In various such embodiments, the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member are between the load transfer dowels.
It should be further appreciated from the above that various embodiments of the present disclosure provide a concrete slab load transfer and connection apparatus comprising: a plurality of load transfer dowels, each dowel including an alignment notch; and a basket supporting the load transfer dowels, the basket including: (1) a first side frame including a first lower elongated member, a first upper elongated member, a plurality of first dowel holding hands connected to the first lower elongated member and the first upper elongated member, (2) a second side frame including a second lower elongated member, a second upper elongated member, a plurality of second dowel holding hands connected to the second lower elongated member and the second upper elongated member, and (3) a plurality of side frame connectors connecting the first side frame and the second side frame, wherein one of the holding hands for each dowel includes an alignment finger extending into the alignment notch for that dowel.
In various such embodiments, each dowel defines opposing alignment notches, and each holding hand includes an alignment finger that extends into one of the alignment notches of one of the dowels.
In various such embodiments, a plurality of first sections of the first upper elongated member and a plurality of second sections of the second upper elongated member are biased outwardly against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.
In various such embodiments, a plurality of first sections of the first upper elongated member and a plurality of second sections of the second upper elongated member are biased inwardly against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.
Various changes and modifications to the above-described embodiments described herein will be apparent to those skilled in the art. These changes and modifications can be made without departing from the spirit and scope of this present subject matter and without diminishing its intended advantages.

Claims

1. A concrete slab load transfer and connection apparatus comprising:

a plurality of load transfer dowels; and

a basket supporting the load transfer dowels, the basket including:

a first side frame including a first lower elongated member, a first upper elongated member, a plurality of first dowel holding hands connected to the first lower elongated member and the first upper elongated member,

a second side frame including a second lower elongated member, a second upper elongated member, a plurality of second dowel holding hands connected to the second lower elongated member and the second upper elongated member, and

a plurality of side frame connectors connecting the first side frame and the second side frame,

wherein a plurality of first sections of the first upper elongated member and a plurality of second sections of the second upper elongated member are biased against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.

2. The concrete slab load transfer and connection apparatus of claim 1, wherein the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member are biased outwardly against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.

3. The concrete slab load transfer and connection apparatus of claim 2, wherein the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member are aligned with the load transfer dowels.

4. The concrete slab load transfer and connection apparatus of claim 2, wherein one of the holding hands for each dowel includes an alignment finger extending into an alignment notch for that dowel.

5. The concrete slab load transfer and connection apparatus of claim 1, wherein the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member are biased inwardly against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.

6. The concrete slab load transfer and connection apparatus of claim 5, wherein the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member are between the load transfer dowels.

7. The concrete slab load transfer and connection apparatus of claim 5, wherein one of the holding hands for each dowel includes an alignment finger extending into an alignment notch for that dowel.

8. The concrete slab load transfer and connection apparatus of claim 1, wherein one of the holding hands for each dowel includes an alignment finger extending into an alignment notch for that dowel.

9. The concrete slab load transfer and connection apparatus of claim 1, wherein each dowel defines opposing alignment notches, and each holding hand includes an alignment finger that extends into one of the alignment notches of one of the dowels.

10. A method of forming a concrete slab load transfer and connection apparatus, said method comprising:

forming a first side frame of a basket including a first lower elongated member, a first upper elongated member, a plurality of first dowel holding hands connected to the first lower elongated member and the first upper elongated member;

forming a second side frame of the basket including a second lower elongated member, a second upper elongated member, a plurality of second dowel holding hands connected to the second lower elongated member and the second upper elongated member;

connecting a plurality of dowels to the first upper elongated member and the first dowel holding hands;

connecting the plurality of dowels to the second upper elongated member and the second dowel holding hands; and

connecting a plurality of side frame connectors to the first side frame and the second side frame, such that a plurality of first sections of the first upper elongated member and a plurality of second sections of the second upper elongated member are biased against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.

11. The method of claim 10, which includes causing the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member to be biased outwardly against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.

12. The method of claim 11, wherein the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member are aligned with the load transfer dowels.

13. The method of claim 10, which includes causing the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member to be biased inwardly against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.

14. The method of claim 10, wherein the plurality of first sections of the first upper elongated member and the plurality of second sections of the second upper elongated member are between the load transfer dowels.

15. A concrete slab load transfer and connection apparatus comprising:

a plurality of load transfer dowels, each dowel including an alignment notch; and

a basket supporting the load transfer dowels, the basket including:

wherein one of the holding hands for each dowel includes an alignment finger extending into the alignment notch for that dowel.

16. The concrete slab load transfer and connection apparatus of claim 15, wherein each dowel defines opposing alignment notches, and each holding hand includes an alignment finger that extends into one of the alignment notches of one of the dowels.

17. The concrete slab load transfer and connection apparatus of claim 16, wherein a plurality of first sections of the first upper elongated member and a plurality of second sections of the second upper elongated member are biased outwardly against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.

18. The concrete slab load transfer and connection apparatus of claim 16, wherein a plurality of first sections of the first upper elongated member and a plurality of second sections of the second upper elongated member are biased inwardly against their natural positions to apply tension to the load transfer dowels to securely connect the load transfer dowels to the basket.