WO2019111170A1

WO2019111170A1 - A concrete starter bar retention and locating device, systems and methods comprising the same

Info

Publication number: WO2019111170A1
Application number: PCT/IB2018/059659
Authority: WO
Inventors: Ernest Comerford
Original assignee: Jiangsu Ernest Technology Co Ltd
Priority date: 2017-12-05
Filing date: 2018-12-05
Publication date: 2019-06-13
Also published as: AU2018378306A1

Abstract

A concrete starter bar retention and locating device(10), more specifically, a starter bar retention device(10) that is configured to receive and engage with a bar coupler(100) attached to a starter bar of a first concrete element. The configuration of the device assists in locating and accessing the starter bar coupler(100) following casting of the first concrete element.

Description

A CONCRETE STARTER BAR RETENTION AND LOCATING DEVICE, SYSTEMS AND METHODS COMPRISING THE SAME

FIELD OF THE INVENTION

The present invention relates to a concrete stater bar retention and locating device, more specifically, a stater bar retention device that is configured to receive and engage with a bar coupler attached to a starter bar of a first concrete element. The configuration of the device of the present invention assists in locating and accessing the starter bar coupler following casting of the first concrete element.

BRIEF DESCRIPTION OF THE PRIOR ART

Steel-reinforced concrete structures are commonly constructed in a plurality of phases whereby one section of the concrete structure is constructed at a time. Each of the concrete sections commonly include steel reinforcing members that are to be interconnected to adjacent sections, which provides improved structural rigidity of the concrete structure. These interconnections are made by using specially designed couplings that are mounted to a coupler bar and then ultimately integrated into the steel reinforcement framework of the concrete structure. Couplers used in concrete structures are well known in the art and commonly use threaded type connections, and include those as described in United States Patent No. 5,664,902; United States Patent No. 5,152,118.

When using embedded couplers and as the concrete structure is formed, the coupler bars and couplings are typically covered in concrete. As such, after the concrete section is poured, but prior to the concrete completely curing, each coupling is required to be located. Once located, the concrete immediately surrounding the embedded coupler must be removed to permit its correct attachment to the next reinforcement member to be used in an adjacent concrete structure. As can be appreciated, this clearing process is labour-intensive and adds significant time and cost to a large-scale construction project. While protective covers that aim to limit damage and concrete influx into couplers are used in the prior art, the removal of these protective convers are still largely a labour- intensive process that can have dramatic cost consequences.

In addition to the foregoing, there are problems with embedded anchor systems used in the prior art as they commonly depend on the second attachment to be screwed into the first embedded coupler. Screwing the second attachment generally requires a tolerance between the threads of the embedded item and the second attachment that will allow the second attachment to be able to be screwed in by hand. This tolerance being large has the effect of producing very large elongation at the connection at very low loads. Also it is possible for workers to merely place the parts so that they look like they are engaged but are only connected by a couple of turns. This is impossible for an inspecting engineer to check unless they try every single connection which is not practicable.

Another method of embedding reinforcing bars proposed within the prior art has been via the use of bent and embedded bars provided inside consumable metal boxes. Following the concrete being poured, the covers of the metal boxes are removed to expose the bent bars. These devices have a number of limitations, such as the fact that they need to be individually carefully measured for placement position for each individual box and that the bent reinforcing bar needs to be restraightened by workers on site often using incorrect tubes to restraighten the reinforcing bars. This practice leads to an "S" shape at the bend point and this "S" shape has the effect of restraightening under load producing large cracks in the concrete if the structure is subjected to any dynamic loading. This can be catastrophic and people can be seriously injured or killed by dislocation of the concrete elements allowed by excessive elongation of the re-bent reinforcing bar at relatively low loads.

As such, it is therefore an object of the present invention to seek to eliminate or ameliorate the disadvantages and limitations of the prior art. Specifically, to provide an efficient and cost-effective device and method for joining consecutive concrete reinforcement members. BRIEF DESCRIPTION OF THE DRAWINGS

By way of illustration only, an embodiment of the present invention is described in more detail hereinafter with reference to the accompanying drawings, in which:

Figure 1 shows a perspective view of a concrete stater bar retaining and locating device in an embodiment of the present invention;

Figure 2 shows an underneath perspective view of a concrete stater bar retaining and locating device in an embodiment of the present invention;

Figures 3 shows a cross section view of an embodiment of the present invention, where a starter bar is shown to be inserted into the aperture.;

Figure 4 shows a side view of a concrete stater bar retaining and locating device in an embodiment of the present invention;

SUMMARY OF THE INVENTION

According to one aspect of the present invention, a concrete stater bar retaining and locating device is provided, the device comprising: a body having an upper and lower surface, the upper surface having at least one transverse aperture formed therein and being configured to receive a bar coupler attached to a first concrete reinforcement element, wherein the upper face comprises a raised portion proximal to the outer rim of the aperture that is adapted to form a void within a concrete structure when poured, the void permitting clear access to an attachment point of the bar coupler when the device is removed from the concrete structure.

Preferably, the aperture is configured to sealably receive the bar coupler such that when concrete is poured an attachment point of the bar coupler is protected from concrete influx.

Preferably, the body further comprises one or more attachment means adapted to secure the body to concrete formwork. Preferably, the one or more attachment means comprises one or more holes formed with a flange that extends from the body, each hole configured to receive a fastener to secure the body to the underlying formwork.

Preferably, the body is a single unit moulded from a thermoplastic.

Preferably, the upper face comprises tapered edges to facilitate removal of the device from cured concrete Preferably, the body comprises a plurality of internal voids to reduce the weight of the device.

Preferably, the internal void comprises a number of strengthening ribs. In another aspect of the present invention, a method of forming a concrete structure is provided, the method having the steps of: providing a formwork shutter having at least one concrete starter bar retaining device attached to its inner surface, the device adapted to receive and retain a plurality of starter bar couplers; locating the formwork shutter into a first position,

inserting a first set of starter bar couplers into the retaining device, the start bar couplers each being attached to an end of a corresponding concrete reinforcing member;

pouring and curing concrete about the formwork at the first position; and relocating the formwork shutter into a second position, whereby the first set of starter bar coupler heads are exposed from the cured concrete at the first position to enable their connection with a corresponding set of opposed coupler heads. Preferably, the set of opposed coupler heads are each attached to a second concrete reinforcing member used in a concrete slab to be tied with the core wall.

Preferably, the concrete structure is a high-rise building.

Preferably, the concrete starter bar retaining device used in the method of the present invention is that disclosed herein.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description of embodiments is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the disclosure, there are shown in the present document example constructions of the disclosure; however, it should be appreciated that the disclosure is not limited to the specific design disclosed in the document and the drawings.

Moving now to Figure 1, a concrete starter bar retaining and locating device (10) of the present invention is shown. The device (10) comprises a body (20) which is preferably manufactured as a single unit using a suitable material of which can retain its shape when covered by significant amounts of concrete. Examples of a suitable materials include a wide variety of commonly known thermoplastics of which can be easily moulded into the body (10) of the present invention. It should be understood, however, that the suitable material used for the device of the present invention is not overly limited and those skilled in the art could routinely select the suitable material.

As is best shown in Figure 2, the body (20) comprises one or more attachment means (22) which are configured to permit the attachment of the device (10) to the formwork shutter (not shown) or alternatively a form-ply rebate former (not shown) when used in forming the concrete structure. The one or more attachment means in a preferred embodiment of the present invention comprises one or more holes formed within a flange (24) that extends outwardly from the body (20). In the embodiment shown in Figure 2, the flange (24) abuts with the surrounding form-ply rebate former. Although an embodiment includes the attachment of the body (20) to a form-ply rebate former (not shown), in other embodiments the flange (24) extends from the base of the body (20) such that the flange (24) abuts directly with the formwork shutter. The one or more holes are sized and configured to each received a suitable fastener to secure the body (20) to the underlying structure to which the flange (24) abuts with.

As shown in Figures 1, 2 and 3, the body has an upper surface (60) and lower surface (62). The lower surface (62) is configured to evenly abut with the formwork shutter (52), whereby the upper surface (60) is the surface facing the concrete structure intended to be poured. Within the body (20) and via the upper face (60), at least one transverse aperture (30) is formed. As shown best in Figure 3, the at least one aperture (30) is configured to receive a bar coupler (100) that has been secured to a first concrete reinforcing member (not shown). By way of example, the first concrete reinforcing member may include a starter bar of a column that will be secured to a second concrete reinforcement member in a subsequent concrete slab.

As shown in Figure 1, it is envisaged that in some embodiments of the present invention the body (20) will include a plurality of apertures (30) each adapted to receive a bar coupler. For example, each of the plurality of apertures (30) would be spaced accordingly to meet the engineered design specifications for the current project, such as but not limited to: 50mm, 100mm, 150mm, 200mm, 300mm centres or the like. For ease of explanation, however, the embodiment shown in Firgues 2 and 3 is the simplest form of the device of the present invention and is shown with only a single aperture (30) adapted to receive a bar coupler (100).

Once again referring to Figure 3, the coupler (100) when inserted into the aperture (30) is substantially sealingly engaged therewith. While not wishing to be bound by theory, this ensures that when concrete is poured around the device (10), little or no concrete intrudes into the portion of the aperture (30) where the connection point (102) of the coupler (100) rests. As the connection point (102) of the coupler is the means via which the coupler will be secured to a second coupler element (not shown) it is important that it remains unobstructed from concrete to ensure a safe and secure connection can be made.

As is best shown in Figures 1 and 4, the upper surface (60) includes a raised portion (70) proximal to the aperture (30). The raised portion (70) provides surface that is sufficiently displaced in a direction X from the connection point of the coupler. In this manner, when concrete is poured around the body a void is formed due to the displacement of the concrete by the raised portion (70).

In one embodiment, the raised portion (70) is a ridge that extends from the outer rim of the aperture (30). However, it should be appreciated that the specific dimensions of the raised portion (70) are not overly limited, provided that the raised portion (70) of the upper surface (60) is sized and configured to ensure that when concrete is cured over the device (10), the formed void is sufficient to permit easy and unhindered access to the connection point (102) of the coupler (100). This easy and unhindered access to the connection point (102) when the device is removed with the formwork following curing of the concrete, ensures a reliable and strong connection can be made with a second coupler element. It also ensures that an engineer can easily visibly insect the connection prior to pouring of the second concrete structure, which significantly increases proper connection compliance and saves time.

The upper surface (60) of the device (10) comprises an external edge that is tapered. This tapered edge improves the removal of the device from the concrete after curing. As the device is intended to be reused when building a structure, this feature ensures significant time can be saved.

While the coupler (100) that is intended to be used with the device (10) of the present invention is not overly limited, it is preferably a coupler that is not a screw type coupler relying on a threaded type connection. A suitable coupler includes those described in Chinese Utility Model Patent No.: ZL2016207930720 and Chinese Utility Model Patent No ZL2016207930720, of which are incorporated herein in their entirety. While the invention has been described with reference to preferred embodiments above, it will be appreciated by those skilled in the art that it is not limited to those embodiments, but may be embodied in many other forms, variations and modifications other than those specifically described. The invention includes all such variation and modifications. The invention also includes all of the steps, features, components and/or devices referred to or indicated in the specification, individually or collectively and any and all combinations or any two or more of the steps or features.

In this specification, unless the context clearly indicates otherwise, the word "comprising" is not intended to have the exclusive meaning of the word such as "consisting only of", but rather has the non-exclusive meaning, in the sense of "including at least". The same applies, with corresponding grammatical changes, to other forms of the word such as "comprise", etc.

Other definitions for selected terms used herein may be found within the detailed description of the invention and apply throughout. Unless otherwise defined, all other scientific and technical terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which the invention belongs.

Claims

CLAIMS:

1. A concrete starter bar retaining and locating device, the device comprising: a body having an upper and lower surface, the upper surface having at least one transverse aperture formed therein and being configured to receive a bar coupler attached to a first concrete reinforcement element, wherein the upper face comprises a raised portion proximal to the outer rim of the aperture that is adapted to form a void within a concrete structure when poured, the void permitting clear access to an attachment point of the bar coupler when the device is removed from the concrete structure.

2. The device of Claim l, wherein the aperture is configured to sealably receive the bar coupler such that when concrete is poured an attachment point of the bar coupler is protected from concrete influx.

3. The device of Claim 1, wherein the body further comprises one or more attachment means adapted to secure the body to concrete formwork.

4. The device of Claim 3, wherein the one or more attachment means comprises one or more holes formed with a flange that extends from the body, each hole configured to receive a fastener to secure the body to the underlying formwork.

5. The device of any one of Claims 1-4, wherein the body is a single unit moulded from a thermoplastic.

6. The device of any one of Claims 1-5, wherein the body comprises a plurality of internal voids to reduce the weight of the device.

7. The device of Claim 6, wherein the internal void comprises a number of strengthening ribs.

8. The device of any one of Claims 1-7, wherein the upper face comprises tapered edges to facilitate removal of the device from cured concrete.

9. A method of forming a concrete structure, the method comprising the steps of:

(a) providing a formwork shutter having at least one concrete starter bar retaining device attached to its inner surface, the device adapted to receive and retain a plurality of starter bar couplers;

(b) locating the formwork shutter into a first position,

(c) inserting a first set of starter bar couplers into the retaining device, the start bar couplers each being attached to an end of a corresponding concrete reinforcing member;

(d) pouring and curing concrete about the formwork at the first position;

(e) relocating the formwork shutter into a second position, whereby the first set of starter bar coupler heads are exposed from the cured concrete at the first position to enable their connection with a corresponding set of opposed coupler heads.

10. The method of Claim 8, wherein the set of opposed coupler heads are each attached to a second concrete reinforcing member used in a concrete slab to be tied with the core wall.

11. The method of Claim 8, wherein the concrete structure is a high-rise building.

12. The method of any one of Claims 9-11, wherein the concrete starter bar retaining device is that define by any one of Claims 1-7.