AU2005100938A4 - Connector device for concrete structures - Google Patents

Description

08/11/2005 14:38 61-3-98901337 PATENT ATTORNEY SERV PAGE 03/13 o CONNECTOR DEVICE FOR CONCRETE STRUCTURES 0 C The present- invention relates to a connector device for concrete structures in O which the casing may be removed from the concrete.

00 Connector devices for concrete structures may also be known as continuity boxes.

0 s One form of known type of connector device for concrete structures comprises a 00 plurality of pre-bent reinforcing bars having portions passing through a wall of a box or Ce 0 cage, typically made of sheet metal, with free end portions of the reinforcing bars disposed within the box. In use, the box or cage is attached to formwork or tied to Sreinforcing means prior to the pouring of the concrete. Protruding portions of the prebent reinforcing bars are set in concrete. Once the concrete pour has taken place, a lid or cover on the box or cage is removed to reveal the free end portions of the pre-bent reinforcing barts. These free ends of the pre-bent reinforcing bars can then be straightened for the required continuity of the reinforcement prior to pouring adjacent concrete.

A problem associated with such known connectors is that prior to the pouring of subsequent concrete, it is desirable to remove the box or cage. However, this becomes difficult as it is difficult to completely straighten the pre-bent reinforcing bars in order to allow for the box or cage to be eased away from the bars. It is not desirable to leave the box or cage in place in that it tends to significantly reduce the bond strength of the concrete in the vicinity of the connector.

In known connector devices the front of the box which is set into the concrete is removed however the back wall remains. This means that for subsequent concrete pour a metal to concrete bond must be formed rather than a concrete to concrete bond. Concrete to concrete bonds are stronger and so it would be desirable to completely remove the box or cage prior to the second concrete pour.

1 COMS ID No: SBMI-01912633 Received by IP Australia: Time 15:36 Date 2005-11-08 08/11/205 14:38 61-3-98901337 PATENT ATTORNEY SERV PAGE 04/13 One prior art suggestion to ameliorate this problems provides a connector device 0 for concrete structures comprising a metal support member which includes a mounting o wall adapted to have at least one reinforcing bar attached thereto and/or passing OO therethrough; and the mounting wall having at least one weakened zone along which sections of the support member are separable from one another. Problems with this 00 suggested solution include the difficulty of tearing the metal boxes along the weakened g zone in order for their removal. Metal is also a heavy and expensive material.

O It is an obiect of the present invention or innovation to overcome or alleviate one O or more of the problems associated with the prior art.

1 '0 According to the present invention or innovation there is provided a connector device for concrete structures including a casing adapted to have at least one reinforcing bar attached thereto and/or passing therethrough, said casing being formed from a plastic sheet material, said sheet having an inner and an outer layer connected by a plurality of ribs.

According to the present invention or innovation there is also provided a method of joining concrete structures together including the steps of: securing a connector device to formwork, reinforcing means or the like, said connector device including a box like casing adapted to have at least one reinforcing bar attached thereto and/or passing therethrough said casing being formed from plastic sheet, said sheet having an inner and an outer layer connected by a plurality of ribs; (ii) passing a plurality of reinforcing bars through openings in said casing before or after step such that protruding sections of the reinforcing bar project outwardly from the outer side of said casing and bent sections of the reinforcing bars on the inner side being disposed so as to extend laterally with respect to the protruding sections; 2 COMS ID No: SBMI-01912633 Received by IP Australia: Time 15:36 Date 2005-11-08 08/11/2005 14:38 61-3-98901337 PATENT ATTORNEY SERV PAGE 05/13 0 (iii) substantially straightening the bent sections of the reinforcing bars once 0said protruding sections thereof have been set in concrete; and o (iv) removing the casing from the concrete.

ZThe connector device is of similar configuration to known continuity boxes.

00 Known continuity boxes comprise a casing that houses pre-bent reinforcing bars which 0project out of the rear of the casing to form a key when cast into concrete. On site, the 2 continuity box is cast into the planned joint surface. After stripping the formwork, the 0_ reinforcement bars are straightened and in the case of the present innovation the casing is removed.

10 The casing of the present invention or innovation is formed from a plastic sheet material. The sheet has an inner and an outer layer connected by a plurality of ribs typically vertical ribs. Any suitable plastic may be used however it has been found that polypropylene sheet is particularly suitable for the purposes of the present invention or innovation. Polypropylene sheet material has the advantage of being cheap and is easily removed from the concrete.

Although solid plastic sheet could be used, it has a disadvantage of being more expensive, heavier and more difficult to foidinto the desired casing shape.

To form the casing into the desired shape, one layer of the sheet may be perforated thereby forming a line of weakness about which the sheet material may be bent.

The casing may be cut from a sheet of the desired plastic. The fold lines may be simultaneously cut into one of the layers of the plastic, The casing may be in the form of a housing within which the bent section of the reinforcing bar is contained. The housing is preferably in the form of a box like structure having a mounting wall, a front wall and side wails.

3 COMS ID No: SBMI-01912633 Received by IP Australia: Time 15:36 Date 2005-11-08 08/11/2005 14:38 88/1/065 1432 61-3-98901337 PATENT ATTORNEY SERV PG 61 PAGE 06/13 In the present invention or innovation, at least one reinforcing bar extends through the mounting wall. A bent sectionl of the reinflorcing bar is disposed on the o inside of the casing and is encased by the casing so as to extend laterally with respect to oc the protruding sections.

0 SThe bent section Of the reinforcing bar is capable of being subsequently 00 straightened after the casing has been set in concrete so that it is generally axially aligned with its, associated protruding section. The casing may be then removed from the reinforcing ba.The material from which. the casing is mnade allows the casing to be removed as it is flexible and there is no need for the various solutions suggested by the prior art such as weakened zones whereby parts of the casing may be removed.

In a further embodiment the at least one reinforcing bar has at least one of its ends connected to an opening in the casing by a coupler. Th)e coupler may be a threaded connector extending through the mounting wall protruding -from one side of the support member and adapted to be attached to the reinforcing members.

Possible and preferred features of the present invention will now be described with particular reference to the accompanying drawings. However it is to be understood that the features illustrated in and described with reference to the drawings are not to be construed as limiting on the scope of the invention, In the drawings: Figure I shows an exploded perspective view of the casing of a connector device of the present invention.

Figure 2 is a perspective view of an assembled connector device of the present invention attached to a surface.

Figure 3 is a perspective view of a connector device of the present invention set in concrete.

4 COMS ID No: SBMI-01912633 Received by IP Australia: Time 15:36 Date 2005-11-08 08/11/2005 14:38 61-3-98901337 PATENT ATTORNEY SERV PAGE 07/13 0 Figure 4 is a perspective view of a connector device of the present invention after c 1 opening or removal of the front of the casing.

o Figure 5 is a perspective view of a connector device of the present invention 00 showing the straightening of the reinforcing bars.

0 Figure 6 shows the reinforcing bars set in concrete after removal of the casing.

00 The components of the embodiment listed in the drawings are marked on the drawings. Therefore the construction and operation of the product and its manner of use can be readily understood by referring to the pending description in conjunction with reference to the drawings.

In Figure 1 there is shown a casing of a connector device of the present invention.

Figure I shows the casing prior to assembly. The casing is constructed from polypropylene corrugated flute board sold under the trade mark "Fluteboard" which was obtained from Corex Plastics. Fluteboard

T

is a one-piece extruded sheet consisting of two flat sheets connected by vertical ribs. It is made from polypropylene and is recyclable. Fluteboard T comes in a variety of weights and thicknesses. 3mm thick Fluteboard was used to form the casing. The outer layer of the casing was precut to give lines of weakness about which the casing was folded to a form a box.

The mounting wall of the box has holes punched therein through which reinforcing bar (not shown) may be inserted. The box includes a stiffener which is also formed from polypropylene to provide structural strength to the box. On the exterior of the casing polypropylene seals were provided to ensure a seal between the holes and the reinforcing bar to avoid concrete seepage into the casing. The reinforcing bars are inserted such that a substantial portion of the pre-bent reinforcing bars are contained within the casing with free end portions, typically of an L-shape or U-shape and shorter COMS ID No: SBMI-01912633 Received by IP Australia: Time 15:36 Date 2005-11-08 08/11/2005 14:39 61-3-98901337 PATENT ATTORNEY SERV PAGE 08/13 S in length than the remaining portion protruding through the openings. The casing is then assembled and taped closed.

o Figures 2 to 6 show the manner of use of the continuity box. The box is not shown in Figures 3 to 6.

00 0 5 In use the connector device is typically attached to formwork and/or surrounding 00 reinforcing members ready for the concrete pour (see Figure After the concrete pour, nthe casing is set in concrete leaving only the front wall of the casing exposed (see Figure o- The front wall is opened or removed typically by cutting with a knife or similar implement and the pre-bent reinforcing bars are exposed ready for straightening (see 10 Figure Using a steel tube or similar tool, the bars are straightened out of the casing (see Figure Once the bars have been straightened, the casing may be removed so that a concrete to concrete interface is formed when the next pour of concrete takes place (see Figure 6).

In a further embodiment of the present invention the connector device can be used with threaded connectors rather than pre-bent reinforcing bars.

A further advantage of the casing of the present invention or innovation is that the entire casing is recyclable.

It is to be understood that various alterations and modifications and/or additions may be made to the features of the possible and preferred embodiments of the invention as herein described without departing from the scope of the invention as defined in the appended claims.

6 COMS ID No: SBMI-01912633 Received by IP Australia: Time 15:36 Date 2005-11-08

Claims (5)

1. A connector device for concrete structures including a casing adapted to have at cx least one reinforcing bar attached thereto and/or passing therethrough, said casing being Z formed from plastic sheet, said sheet having an inner and an outer layer connected by a 00O5 plurality of ribs.

2. A connector device as claimed in claim I wherein the sheet is polypropylene 00 sheet material having an inner and an outer layer connected by vertical ribs.

3. A connector device as claimed in clailn or 2 wherein the at least one reinforcing in bar extends through a mounting wall of said casing with an outwardly protruding section 0 10 from one side of said casing and a bent section of the reinforcing bars being disposed on the other side of the casing so as to extend laterally with respect to the protruding section.

4. A connector device as claimed in any one of claims I to 3 wherein said casing is in the form of a box like housing within which the bent section of the reinforcing bar is contained.

5. A method ofjoining concrete structures together including the steps o.f: securing a connector device to forrnwork: reinforcing means or the like, said connector device including a box like casing adapted to have at least one reinforcing bar attached thereto and/or passing tberethrough said casing being formed from plastic sheet, said sheet having an inner and an outer layer connected by a plurality of ribs; (ii) passing a plurality of reinforcing bars .through openings in said casing before or after step such that protruding sections of the reinforcing bar project Outwardly from the outer side of said casing and bent sections of the reinforcing bars on the inner side being disposed so as to extend laterally with respect to the protruding sections; 7 COMS ID No: SBMI-01912633 Received by IP Australia: Time 15:36 Date 2005-11-08 08/11/2005 14:38 61-3-98901337 PATENT ATTORNEY SERV PAGE 10/13 t (iii) substantially straightening the bent sections of the reinforcing bars once O said protruding sections thereof have been set in concrete; and O (iv) removing the casing from the concrete. 00 Dated this 8th day ofNovember 2005 00 PATENT ATTORNEY SERVICES 0\ Attorneys for o ICF CONTRACTING PTY LTD in ci (NS COMS ID No: SBMI-01912633 Received by IP Australia: Time 15:36 Date 2005-11-08