For various logistical and technical reasons, concrete floors often include a series of individual cast-in-place concrete slabs. These concrete slabs provide several advantages including relief of internal stresses due to curing, shrinkage, and thermal movement. There are various known issues with such concrete slabs. These issues often involve the joint between concrete slabs, the interface where one concrete slab meets another concrete slab, and the relative vertical movement of adjacent concrete slabs.
More specifically, freshly poured concrete shrinks considerably as it cures and hardens due to the chemical reaction that occurs between the cement and water. As the concrete shrinks, tensile stress accumulates in the concrete resulting in joint openings. The joint openings create discontinuities in the concrete floor surface that can cause the wheels of a vehicle (such as a forklift truck) to impact the edges of the adjacent concrete slabs that form the joint and chip small pieces of concrete from the edge of each concrete slab, particularly if the concrete slabs move too far away from each other. This damage to the edges of concrete slabs is commonly referred to as joint spalling. Joint spalling can interrupt the normal working operations of a facility by slowing down forklift and other truck traffic, and/or causing damage to trucks and the carried products. Joint spalling can also be expensive and time consuming to repair.
It is known to connect adjacent concrete slabs by tie-bars such as rebar to reduce the movement of the concrete slabs relative to one another. One technique for forming such adjacent concrete slabs employs a form that supports the tie-bars such as illustrated in
To ensure proper placement of the tie-bars 20 in the concrete slabs, the tie-bars 20 must be held firmly in the form 30. If the tie-bars 20 are not held firmly, they can shift when the concrete is poured resulting in improper placement. Improperly placed tie-bars can create undesirable stresses in the cured concrete. To hold the tie-bars firmly, the holes 36 in the form 30 are sized to create a tight fit to the tie-bar 20, or even an interference fit. This tight fit creates problems after the first concrete slab cures because the form 30 with the multiple tie-bars 20 is difficult to remove. This can increase labor costs and construction time during construction. In certain instances, the form 30 needs to be cut to remove it, rendering the form no longer useable and requiring additional labor and material.
Accordingly, there is a need for improved tie-bar assemblies.
Various embodiments of the present disclosure provide an assembly that solves the above problem. Various embodiments of the present disclosure provide a tie-bar assembly including a tie-bar pocket, a first tie-bar attachable to the tie-bar pocket, and a second tie-bar attachable to the tie-bar pocket in a manner such that the second tie-bar is coupled to the first tie-bar. During construction, the first tie-bar is attached to the tie-bar pocket. This assembly is fastened to concrete form. After the first concrete slab is poured, the first tie-bar and the tie-bar pocket are embedded in the first concrete slab. The form is removed, and the interior of the tie-bar pocket is exposed, and the bent portion of the first tie-bar is accessible. The bent portion of the second tie-bar is then inserted into the tie-bar pocket and is coupled with the bent portion of the first tie-bar in the tie-bar pocket. The second concrete slab is then poured and encapsulates the second tie-bar.
Additional features and advantages of the present invention are described in, and will be apparent from, the following Detailed Description and the Figures.
While the systems, devices, and methods described herein can be embodied in various forms, the drawings show, and the specification describes certain exemplary and non-limiting embodiments. Not all components shown in the drawings and described in the specification can be required, and certain implementations can 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 can 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, connected, etc., are not intended to be limited to direct mounting methods but should be interpreted broadly to include indirect and operably mounted, 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.
The tie-bar assembly 100 includes: (1) a tie-bar pocket 200; (2) a first tie-bar 400; and (3) a second tie-bar 600. The first tie-bar 400 is insertable in and connectable to the tie-bar pocket 200, and the second tie-bar 600 is insertable in and connectable to the tie-bar pocket 200. Generally, (a) the tie-bar pocket 200 and the first tie-bar 400 are configured to be positioned in a first concrete slab, (b) the second tie-bar 600 is configured to be positioned in the tie-bar pocket 200 and in an adjacent second concrete slab, and (c) the second tie-bar 600 is additionally configured to be coupled to the first tie-bar 400 in the tie-bar pocket 200.
The tie-bar pocket 200 is configured to be attached to a conventional form 30 before the first concrete slab 80 is poured such that the tie-bar pocket 200 extends into the first concrete slab 80 and is maintained in the first concrete slab 80 after the first concrete slab 80 is poured, cured, and hardened such as shown in
The first tie-bar 400 is configured to be attached to the tie-bar pocket 100 before the first concrete slab 80 is poured such that the first tie-bar 400 extends into the first concrete slab 80 and is maintained in the first concrete slab 80 after the first concrete slab 80 is poured, cured, and hardened such as shown in
An example embodiment of the first tie-bar 400 is illustrated in
The second tie-bar 600 is configured to be attached to the tie-bar pocket 100 after the first concrete slab 80 is poured, cured, and hardened and before the second concrete slab 90 is poured such that it is maintained in the second concrete slab 90 after the second concrete slab 80 is poured, cured, and hardened as shown in
The tie-bar pocket 200 includes: (1) an attachment wall 210; (2) a first fastener guide 240 connected to and extending from the attachment wall 210; (3) a second fastener guide 250 connected to and extending from the attachment wall 210; (4) a first pocket 260 connected to and extending from the attachment wall 210; and (5) a second pocket 300 connected to and extending from the attachment wall 210.
The attachment wall 210 includes a generally flat partially rectangular member 212 having a front surface 214, a back surface 216, a top edge 218, a bottom edge 220, a first side edge 222, and a second side edge 224. The attachment wall 210 also includes two sets of outwardly extending alignment tabs including tabs 230, 232, 234, and 236 in this example embodiment for the purposes described below. In other embodiments, the attachment wall 210 can be non-rectangular and/or could exclude one or more of these alignment tabs. The alignment tabs can also be alternatively formed in accordance with the present disclosure.
The first fastener guide 240 includes a generally straight first section 242 integrally formed with, connected to, and extending rearwardly from the back surface 216 of the attachment wall 210.
The second fastener guide 250 includes a generally straight first section integrally formed with, connected to, and extending rearwardly from the back surface 216 of the attachment wall 210.
The fastener guides 240 and 250 respectively define openings 244 and 254 configured to respectively receive fasteners such as nails 40 such as shown in
The first pocket 260 includes a tie-bar body boss 270, a tie-bar elbow receiver 272, and a tie-bar end receiver 274.
The tie-bar body boss 270 extends from the attachment wall 210. The tie-bar body boss 270 defines a tie-bar receiving opening 262 sized, shaped, and otherwise configured to receive a portion of the body 420 of the first tie-bar. The tie-bar receiving opening 262 extends through the tie-bar body boss 270. When the first tie-bar 400 is inserted into the tie-bar pocket 200, the straight end 402 of the first tie-bar 400 extends out of the tie-bar pocket 200 away from the attachment wall 210 and a portion of the tie-bar body 420 is retained in the tie-bar body boss 270. In certain example embodiments, the members that define the tie-bar receiving opening 262 can be configured to have a low-clearance fit to the first tie-bar 400, an interference fit with the first tie-bar 400, or can include ribs 268 to assist in holding the first tie-bar 400.
The tie-bar elbow receiver 272 extends from the attachment wall 210 and also extends between the tie-bar body boss 270 and the tie-bar end receiver 274. The tie-bar elbow receiver defines a tie-bar elbow channel 266. The tie-bar elbow receiver 272 and the tie-bar elbow channel 266 have a curved shape to receive the elbow 410 of the first tie-bar 400.
The tie-bar end receiver 274 extends from the attachment wall 210 and connects to the tie-bar elbow receiver 272. The tie-bar end receiver 274 defines a tie-bar end channel 262 that receives the end of the first tie-bar 412. In certain example embodiments, the tie-bar end 264 channel or the tie-bar elbow channel 266 can be configured to have a snap fit to the first tie-bar 400 to further secure it in place.
The second pocket 300 includes a tie-bar body receiver 310, a tie-bar elbow receiver 312, and a tie-bar end receiver 314.
The tie-bar body receiver 310 defines a tie-bar body channel 302 configured to receive the tie-bar body 420 of the second tie-bar 600. The tie-bar end receiver 274 defines a tie-bar end channel 304 configured to receive the elbow end 412 of the second tie-bar 600. The tie-bar elbow receiver defines a tie-bar elbow channel 306. The tie-bar elbow receiver 312 and the tie-bar elbow channel 306 are curved to receive the elbow 410 of the second tie-bar 600.
During assembly, after removal of the form 30, the elbow end 412 of the elbow 410 of the second tie-bar is insertable into the tie-bar body channel 302 and the second tie-bar 600 is then rotatable such that the elbow end 412 traverses the curved portion of the tie-bar elbow channel 306 until the second tie-bar is fully seated in the second pocket 300. When the second tie-bar 600 is fully seated, the tie-bar body channel 302 has received a portion of the tie-bar body 420, the tie-bar elbow channel 306 has received the elbow 410 of the tie-bar, and the tie-bar end channel 304 has received the elbow end 412 of the second tie-bar 600. In certain example embodiments, the tie-bar body channel 302 and/or the tie-bar end channel 304 can be configured to have a snap fit to the second tie-bar 600 to further secure it in place. In certain example embodiments this snap fit can be accomplished with ribs 308 located in the tie-bar body channel 302 and/or the tie-bar end channel 304.
In the illustrated example, the tie-bar pocket 200 has a preferred orientation. However, other example embodiments can be formed to be symmetrical about one or more axes, enabling the tie-bar pocket 200 to be used in two or more orientations.
The tie-bar pocket 200 is made from a suitable plastic (such as a High Impact Polystyrene (HIPS)) in this example embodiment, but can be made from other suitable materials.
The tie-bar pocket 200 is monolithically formed as a single molded unit, in this example embodiment, but can be made from multiple connected parts in other embodiments.
The tie-bar pocket 200 includes multiple tapered outer surfaces 280 and large radiused corners 282 or connections that cause air bubbles to be propelled towards the edges of pocket. This enables air adjacent to those members to flow uninterrupted along the outer surfaces of those members and to escape from being trapped under or adjacent to those members. These radiused edges and apexes also minimize perimeter point loads.
In certain example embodiments, the tie-bar pocket 200 can include a paper face or label 286. This label 286 prevents concrete from entering the interior of the tie-bar pocket when the concrete is poured. After the form 30 is removed, the label 286 is removed, allowing insertion of the second tie-bar 600.
It should be appreciated from the above that various embodiments of the present disclosure provide a tie-bar assembly for a first concrete slab and a second concrete slab, the tie-bar assembly comprising: a tie-bar pocket; a first tie-bar is insertable in and connectable to the tie-bar pocket; and a second tie-bar insertable in and connectable to the tie-bar pocket, wherein the tie-bar pocket and the first tie-bar are configured to be positioned in a first concrete slab, wherein the second tie-bar is configured to be positioned in the tie-bar pocket and in an adjacent second concrete slab, and wherein the second tie-bar is configured to be coupled to the first tie-bar in the tie-bar pocket. In various such embodiments, the second tie-bar is configured to be positioned in the tie-bar pocket after the first concrete slab is poured and before the second concrete slab is poured. In various such embodiments, the tie-bar assembly is configured to be attached to a leave-in-place form for continuous pouring of the first concrete slab and the second concrete slab. In various such embodiments, the second tie-bar includes an elbow. In various such embodiments, the first tie-bar includes an elbow, and the elbow of the second tie-bar is couplable to the elbow of the first tie-bar in the tie-bar pocket. In various such embodiments, the tie-bar pocket includes a first pocket configured to receive the first tie-bar and a second pocket configured to receive the second tie-bar. In various such embodiments, the first pocket of the tie-bar includes a tie-bar body boss, a tie-bar elbow receiver, and a tie-bar end receiver. In various such embodiments, the tie-bar body boss defines a tie-bar receiving opening; the tie-bar elbow receiver defines a tie-bar elbow channel; and the tie-bar end receiver defines a tie-bar end channel. In various such embodiments, the tie-bar body boss is configured to secure the first tie-bar. In various such embodiments, the second pocket of the tie-bar assembly includes a tie-bar body receiver, a tie-bar elbow receiver, and a tie-bar end receiver. In various such embodiments, the tie-bar body receiver defines a tie-bar body channel; the tie-bar elbow receiver defines a tie-bar elbow channel; and the tie-bar end receiver defines a tie-bar end channel. In various such embodiments, the second pocket of the tie-bar pocket is configured to secure the second tie-bar. In various such embodiments, the second pocket of the tie-bar pocket includes snap fit ribs to secure the second tie-bar.
It should further be appreciated from the above that various embodiments of the present disclosure provide a tie-bar pocket for a first concrete slab and a second concrete slab, the tie-bar pocket comprising: an attaching wall configured to be attached to a concrete form; a first pocket connected to and extending from the attaching wall and configured to receive a first tie-bar; and a second pocket connected to and extending from the attaching wall and configured to receive a second tie-bar insertable. In various such embodiments, the first pocket is configured to receive the first tie-bar and the second pocket is configured to receive the second tie-bar. In various such embodiments, the first pocket includes a tie-bar body boss, a tie-bar elbow receiver, and a tie-bar end receiver. In various such embodiments, the tie-bar body boss defines a tie-bar receiving opening; the tie-bar elbow receiver defines a tie-bar elbow channel; and the tie-bar end receiver defines a tie-bar end channel. In various such embodiments, the tie-bar body boss is configured to secure the first tie-bar. In various such embodiments, the tie-bar body boss includes ribs configured to secure the first tie-bar. In various such embodiments, the second pocket includes a tie-bar body receiver, a tie-bar elbow receiver, and a tie-bar end receiver. In various such embodiments, the tie-bar body receiver defines a tie-bar body channel; the tie-bar elbow receiver defines a tie-bar elbow channel; and the tie-bar end receiver defines a tie-bar end channel. In various such embodiments, the second pocket is configured to secure the second tie-bar. In various such embodiments, the second pocket includes snap fit ribs configured to secure the second tie-bar. In various such embodiments, the tie-bar pocket includes one or more alignment tabs configured to align the tie-bar pocket with an adjacent flat plate dowel pocket. In various such embodiments, the one or more alignment tabs includes two sets of alignment tabs alignable with an adjacent flat plate dowel pocket. In various such embodiments, the tie-bar pocket includes one or more fastener guides.
It should further be appreciated from the above that various embodiments of the present disclosure provide a pair of tie-bars for a first concrete slab and a second concrete slab, the pair of tie-bars comprising: a first tie-bar including a body extending along a first straight axis and a first elbow; and a second tie-bar including a body extending along a second straight axis and a second elbow, wherein the first elbow of the first tie-bar and the second elbow of the second tie-bar are configured to be coupled to each other in a tie-bar pocket. In various such embodiments, an end of the first elbow is bent away from the first straight axis by a predefined angle, and an end of the second elbow is bent away from the second straight axis by the predefined angle. In various such embodiments, the predefined angle enables each of the first and the second elbows to be engaged with the other of the first and second elbow by rotating the tie-bar through an angle less than ninety degrees. In various such embodiments, the predefined angle is less than one hundred eighty degrees. In various such embodiments, the predefined angle is less than ninety degrees. In various such embodiments, the predefined angle is greater than ninety degrees and less than one hundred eighty degrees.
It should further be appreciated from the above that various embodiments of the present disclosure provide a tie-bar for joining adjacent cast-in-place concrete slabs, the tie-bar comprising: a body extending along a straight axis; and an elbow configured to be coupled to a second tie-bar in a tie-bar pocket. In various such embodiments, an end of the elbow is bent away from the axis by a predefined angle. In various such embodiments, the predefined angle enables the elbow to be engaged with another tie-bar by rotating the tie-bar through an angle less than ninety degrees. In various such embodiments, the predefined angle is less than one hundred eighty degrees. In various such embodiments, the predefined angle is less than ninety degrees. In various such embodiments, the predefined angle is greater than ninety degrees and less than one hundred eighty degrees. In various such embodiments, the elbow is configured to couple to the elbow of the second tie-bar. In various such embodiments, the second tie-bar is identical to the tie-bar.
The present disclosure further illustrates one example method of installing the tie-bar assembly in a first cast-in-place concrete slab 80 and a second cast-in-place concrete slab 90.
The method includes the steps of: (1) placing an edge form 30 on the ground or other suitable substrate; (2) inserting the first tie-bar 400 in the tie-bar pocket 200 (if the first tie-bar 400 and tie-bar pocket 200 are not provided pre-assembled); (3) attaching the tie-bar pocket 200 to the edge form 30 such that part of the tie-bar pocket 200 extends into the area where the first concrete slab 80 will be formed; (4) pouring the concrete material which forms the first concrete slab 80; (5) allowing the first concrete slab 80 to cure and harden to a certain degree; and (6) removing the edge form 30 from the first concrete slab 80 such that the tie-bar pocket 200 and the first tie-bar 400 remain within and attached to the first concrete slab 80. It should be appreciated that the removal of the form 30 is substantially easier and quicker than the removal of the edge form described above. Because the first tie-bar does not penetrate the form 30, the form 30 does not require the tight fit described above. Since only the fasteners 40 hold the form 30 to the tie-bar pocket 200, the form 30 can be easily separated from the fasteners 40 using conventional tools (such as a pry bar). Unlike the long, straight tie-bars described above, the fasteners 40 are relatively short, so only a few inches (cm) of travel are required to separate them from the form 30.
The method further includes: (7) inserting a second tie-bar 600 into the tie-bar pocket 200 such that the second tie-bar protrudes into a second area where the second concrete slab 90 will be formed; (8) pouring the concrete material that forms the second cast-in-place concrete slab 90 into the second area where the second concrete slab 90 will be formed; and (9) allowing the second concrete slab 90 to cure and harden. This method enables the two concrete slabs 80 and 90 to be tied together in the axial direction of the tie-bars 400 and 600 to minimize the extent that the slabs 80 and 90 shrink away from each other.
In other example methods, the tie-bar assembly 100 can be employed with leave-in-place formwork. In one such example, the leave-in-place form can be a prefabricated metal form (not shown). Such a prefabricated form can include specially-shaped cutouts to allow insertion of the second tie-bar 600. Alternatively, a form (wooden or prefabricated metal) can include a clearance hole such that the second tie-bar 600 can be assembled in the tie-bar pocket 200 and then extend through the clearance hole when the tie-bar assembly 100 is attached to the leave-in-place form.
The use of the tie-bar pocket assembly 100 during construction constrains the shrinkage and movement of the concrete slabs along the axes 432 of the first tie-bar 400 and second 600, but provide only limited constraint in the vertical direction. This can enable concrete slabs to shift vertically relative to one another, resulting in an undesirable lip at the joint. Therefore, in another example embodiment, the tie-bar pocket 200 can be used in conjunction a flat plate dowel pocket 1000. An example flat plate dowel pocket is described in U.S. Pat. No. 6,354,760, which is incorporated by reference in its entirety herein. When the tie-bar pocket 200 is used with a flat plate dowel pocket 1000, the alignment tabs 234 and 236 can be mated or aligned with corresponding alignment tabs 1010 and 1020 or another portion of the flat plate dowel pocket 1000. In this way, the tie-bar pocket 200 and the flat plate dowel pocket 1000 can be easily aligned along a common horizontal plane 1100. As with the tie-bar pocket 100, the interior 1040 of the flat plate dowel pocket 1000 is exposed by removing the form 30 after the first concrete slab 80 is cured. A flat tie-bar (described in the above-referenced patent, but not shown here) can be inserted into the flat plate dowel pocket. When the second concrete slab 90 is poured and cured the flat plate dowel will constrain the relative motion of the two slabs in the vertical direction. It should be appreciated that the flat tie-bar plate pocket can be provided with the fasteners positioned in the fastener channels, and with the load transfer plate bracing insert in the chamber, and with direction tape positioned on the opening in the attachment member.
It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present subject matter and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.
This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63/578,527, filed Aug. 24, 2023, the entire contents of which are incorporated herein by reference.
Number | Date | Country | |
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63578527 | Aug 2023 | US |