AU2015224431A1

AU2015224431A1 - A concrete formwork brace and method of bracing concrete formwork

Info

Publication number: AU2015224431A1
Application number: AU2015224431A
Authority: AU
Inventors: Shanon Matthew Martin; David Kim Scott
Original assignee: Probrace Systems Ltd
Current assignee: Probrace Systems Ltd
Priority date: 2014-09-12
Filing date: 2015-09-09
Publication date: 2016-03-31
Also published as: US20160076262A1

Abstract

A concrete formwork brace having a base, a bracket configured to support a concrete formwork and a pair of adjustable arms. A first length adjustable arm is connected to 5 the base and the bracket and a second arm is connected to the base and the bracket. The connection between the first arm and the base is vertically offset from the connection between the second arm and the base and the connection between the first arm and the bracket is vertically offset from the connection between the second arm and the bracket. The first arm is length adjustable such as to adjust the orientation of 10 the bracket. C\| -------- co

Description

1 A CONCRETE FORMWORK BRACE AND METHOD OF BRACING CONCRETE FORMWORK FIELD OF THE INVENTION 5 The invention relates to concrete formwork braces and methods of bracing concrete formwork. BACKGROUND TO THE INVENTION 10 In the construction industry concrete forms, or formwork include barriers and moulds that hold concrete or other cementitious material while it hardens to assume a desired shape. Braces have been suggested to hold the formwork in the required position, resisting the strong forces which wet concrete exerts against formwork. For example, 15 wood props may be anchored to the ground with pegs and secured to formwork. This often results in damage to the formwork and wooden props as screws or other fasteners create holes in the wood. Such systems of wooden bracing can be wasteful and costly. Removing bracing from the formwork is often invasive as fasteners are pried out. 20 Concrete that has not sufficiently hardened will be damaged by early removal of bracing or formwork. Generally, current types of bracing must stay in place at least overnight. Although prior braces can be fastened in different positions to provide some variation in 25 position, once the braces are fastened to the formwork they are generally set in place and they cannot be re-adjusted without un-fastening and refastening. To provide some adjustment, bracing has been provided with an extendable strut or arm. Other known braces have employed "pivot points" for angular adjustment of a 30 diagonal strut included in the brace. However the ability to readily adjust the brace can sometimes compromise the rigidity of the brace and its ability to keep the formwork in 2 place. Furthermore, improvements can be made to the precision and ease of brace adjustments. Prior braces have failed to rest properly on uneven or sloping surfaces without 5 compromising the functioning of the brace. Prior braces are often difficult and cumbersome to assemble, and therefore time consuming to install. 10 Reference to any prior art in this specification does not constitute an admission that such prior art forms part of the common general knowledge. It is an object of the invention to provide an improved concrete formwork brace and/or method of bracing which overcomes or at least ameliorates some or all of the above 15 shortcomings, or to at least provide the public with a useful choice. SUMMARY OF THE INVENTION According to one aspect the invention provides a concrete formwork brace including: a 20 base, a bracket configured to support a concrete formwork, a first length adjustable arm, connected to the base and the bracket, and a second arm connected to the base and the bracket; wherein the connection between the first arm and the base is vertically offset from the connection between the second arm and the base, wherein the connection between the first arm and the bracket is vertically offset from the connection between 25 the second arm and the bracket; and wherein the first arm is length adjustable such as to adjust the orientation of the bracket. Preferably the second arm is length adjustable. 30 Preferably the connection between the first arm and the base is horizontally offset from the connection between the second arm and the base.

3 Preferably the connection between the first arm and the base is at a first end of the base and the connection between the second arm and the base is at an intermediate position between the first end of the base and a second end of the base. 5 Preferably the connection between the second arm and the base is centrally located on the base. Preferably the connection between the second arm and the base is vertically elevated 10 relative to the connection between the first arm and the base. Preferably the base has mounting features for securing the base to a ground surface. Preferably the mounting features are apertures configured to receive fasteners for 15 securing the base to a ground surface. Preferably the bracket has mounting features for securing the bracket to formwork. Preferably the bracket has apertures configured to receive fasteners securing the bracket 20 to formwork Preferably the bracket is configured to rest, in use, on a ground surface. Preferably the bracket is height-adjustable. 25 Preferably the brace includes a level indicator. Preferably the first length adjustable arm is length-adjustable by rotation of a threaded element. 30 Preferably the second arm is length-adjustable by rotation of a threaded element.

4 Preferably the connection between the first arm and the bracket is a pivotal connection and the connection between the second arm and the bracket is a pivotal connection. 5 Preferably the connection between the first arm and the base is a pivotal connection and the connection between the second arm and the base is a pivotal connection. This aspect also extends to a method of bracing a concrete formwork, the method including the steps of: arranging the concrete formwork brace adjacent the concrete 10 formwork, with the bracket facing the concrete formwork, securing the base to the ground or other underlying support; adjusting one or more of the first and second arms relative to the base and the bracket, to adjust the orientation and/or position of the bracket. 15 According to a second aspect the invention provides a concrete formwork brace including: a base; and a bracket supported by the base, the bracket including: a first engagement element configured to engage with a cooperating second engagement element on a concrete formwork to define a releasable connection between the bracket and the formwork. 20 Preferably the releasable connection is a clamp connection. Alternatively the releasable connection is a hook connection. 25 Preferably, in use, in an engaged state the bracket is flush against the formwork. Preferably the second engagement element includes a protrusion. Preferably the protrusion is located in a recess of the bracket when the bracket and the 30 formwork are connected.

5 Preferably the actuator is a lever. Alternatively the actuator is a latch. 5 Alternatively the actuator is a twist lock actuator. Preferably the actuator is removable from the bracket. Preferably the formwork is wooden. 10 Alternatively the formwork is metal. Optionally the second engagement element is inserted into a channel in the formwork. 15 Preferably the second engagement element acts as a spacer when formwork is arranged in stacks. This aspect also extends to a method of releasably engaging formwork to a concrete formwork brace, the method including the steps of: creating or securing a second 20 engagement element on the formwork, arranging the concrete formwork brace adjacent the formwork, with the bracket facing the concrete formwork, and ; engaging the first engagement element with the second engagement element. This aspect also extends to a concrete formwork system including: one or more 25 concrete formwork braces; and concrete formwork including one or more second engagement elements configured to cooperate with one of the first engagement elements. This invention also extends to concrete formed by the method of the first aspect and/or 30 the method of the second aspect.

6 BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described by way of example only, with reference to the accompanying drawings, in which: 5 Figure 1 shows a perspective view of a concrete formwork brace according to an embodiment of the present invention; Figure 2 shows a right side view of the concrete formwork brace of Figure 1; Figure 3 shows a back view of the concrete formwork brace of Figure 1; 10 Figure 4 shows a front view of the concrete formwork brace of Figure 1; Figure 5 shows a top view of the concrete formwork brace of Figure 1; Figure 6 shows a left side view of the concrete formwork brace of Figure 1; Figure 7 shows a bottom view of the concrete formwork brace of Figure 1; Figure 8 shows a front view of a concrete formwork brace with the bracket 15 arranged in a first exemplary inclination; Figure 9 shows a front view of a concrete formwork brace with the bracket arranged in a second exemplary inclination; Figure 10 shows a set of concrete formwork braces according to an embodiment of the present invention supporting formwork; 20 Figure 11 a shows an embodiment of a second engagement element according to an embodiment of the present invention; Figure 11 b shows a cross section of the second engagement element of Figure 11 a; Figure 12 shows another embodiment of a second engagement element according to an embodiment of the present invention; 25 Figure 13a shows another embodiment of a second engagement element according to an embodiment of the present invention; Figure 13b shows a cross section of the second engagement element of Figure 13a; Figure 14 shows another embodiment of a second engagement element according to an embodiment of the present invention; 30 Figure 15 shows another embodiment of a second engagement element according to an embodiment of the present invention; 7 Figure 16 shows another embodiment of a second engagement element according to an embodiment of the present invention; Figure 17 shows another embodiment of a second engagement element according to an embodiment of the present invention; 5 Figure 18 shows a bracket releasably secured to formwork according to an embodiment of the present invention; and Figure 19 shows a pile of stacked formwork according to an embodiment of the present invention. 10 DETAILED DESCRIPTION The invention relates to concrete formwork braces and methods of bracing concrete formwork. "Concrete" in this context may relate to any cementitious material used in construction which hardens to assume a desired shape or configuration including but 15 not limited to materials including concrete, cements and limes. "Formwork" includes any suitable barriers or moulds for supporting concrete in a desired shape or configuration while it hardens. This may include wooden, metal or plastic formwork, but the invention is not limited in this respect. Formwork may be used in formation of concrete slabs, foundations, panels, monolithic structures or any other suitable 20 cementitious structure. Figures 1-7 show a concrete formwork brace 1 according to an embodiment of the present invention. The brace 1 includes a base 2 and a bracket 3 configured to support a concrete formwork (not shown). The brace 1 includes a first length adjustable arm 4 25 and a second arm 5. The first arm 4 is length adjustable such as to adjust the orientation of the bracket 3 relative to the base 2. Preferably, the second arm 5 is also length adjustable, however in some embodiments this is not a necessity. In other embodiments the second arm may be length adjustable while the first arm is fixed in length. 30 8 Both the first arm 4 and the second arm 5 are pivotally connected to the bracket 3. In some embodiments the first arm 4 and the second arm 5 may also be pivotally connected to the base 2. As shown in Figure 2, the connection 6 between the first arm 4 and the base 2 is vertically offset from the connection 7 between the second arm 5 5 and the base 2. The vertical offset is shown by arrow A of Figure 2. In the embodiment shown the connection 7 between the second arm 5 and the base 2 is vertically elevated relative to the connection between the first arm 4 and the base. The vertical offset provides improved adjustability of the bracket, and also allows room to insert a power tool to adjust the length of the first arm 4 or the second arm 5, as discussed below. 10 Further, the pivotal connection 8 between the first arm 4 and the bracket 3 is vertically offset from the pivotal connection 9 between the second arm 5 and the bracket 3. This vertical offset is shown by arrow B in Figure 2. Thus the four pivotal connections 6, 7, 8 and 9 are arranged in a quadrilateral shape. This provides a highly stable and 15 adjustable structure. Preferably, the connection 6 between the first arm 4 and the base 2 is also horizontally offset from the connection 7 between the second arm 5 and the base 2. This horizontal offset is shown by arrow C in Figure 2. The pivotal connection 6 between the first arm 4 20 and the base 2 is preferably at a first end 10 of the base 2 and the pivotal connection 7 between the second arm 5 and the base 2 is at an intermediate point between the first end 10 of the base 2 and a second end 11 of the base. The pivotal connection 7 between the second arm 5 and the base 2 may be generally centrally located on the base 2. 25 Referring now to the top view of Figure 5, the base 2 will preferably have mounting features 12 for securing the base 2 to a ground surface. In this embodiment, the mounting features are apertures 12 through which stakes (not shown) can be inserted to secure the base 2 to the ground. A person skilled in the art can readily envisage other 30 ways in which to secure the base to the ground, and the invention is not limited in this respect.

9 Preferably, the bracket 3 also includes mounting features for securing the bracket 3 to concrete formwork. In the shown embodiment, these are apertures for receiving fasteners (screws, nails etc), however they may be any other suitable mounting features. 5 As will be discussed later in the specification, in an alternative embodiment these mounting features may be part of a quick release mechanism for attachment / release of the bracket to / from the formwork. In use the bracket 3 may rest on a ground surface. This is accomplished by way of a 10 foot 14 (Figure 1). The concrete formwork brace 1 may also include a level indicator (not shown), for assisting a user to arrange the geometry of the brace in a desired orientation. 15 The length-adjustment of the arms may be effected through any suitable mechanism. In the shown embodiment, arm length is adjusted by rotation of a threaded element. This may be adjusted manually or using a power tool. A first portion 5a of each arm includes a threaded section (not visible in Figure 2). A handle portion 5b has internal threading complimentary to that of threaded section of the first portion 5a. As the handle portion 20 5b is rotated, it drives the first portion 5a to extend or retract the first portion relative to the handle 5b. This lengthens or shortens the overall length of the arm 5. The arm 4 may be similarly constructed. In order to adjust the length of the first or second arm 4, 5, a user may manually twist 25 the handle portion 5b. Alternatively, the Applicant's brace allows powered adjustment of arm length. Each arm includes a drive head 4c, 5c, with a suitable shape for receiving a drive bit from a power tool such as a handheld power drill. Each drive head 4c, 5c is linked to the threaded drive mechanism described above. Rotation of the drive head 4c, 5c will cause rotation of the handle portion 4b, 5b relative to threaded 30 section of each first portion 4a, 5a of the arms 4, 5.

10 Figures 8 and 9 show the bracket 3 in two different positions relative to the base, in order to illustrate the adjustability of the bracket's position and orientation. Figure 8 shows a front view of a concrete formwork brace with the bracket arranged in 5 a first exemplary inclination. In this embodiment the second arm 5 has been extended relative to the first arm 4 to push the upper part of the bracket 3 outwards, thus creating an inclined orientation of the bracket. Figure 9 shows a front view of a concrete formwork brace with the bracket arranged in 10 a second exemplary inclination. In this embodiment the first arm 4 has been extended relative to the second arm 5 to push the lower part of the bracket 4 outwards, thus creating an orientation of the bracket with the opposite inclination to that shown in Figure 8. 15 Further, the bracket 3 may include a first portion 3a mounted to the first and second arms and a second portion 3b mounted to the first portion 3a. The second portion 3b may be adjustable relative to the first portion by rotation of a drive screw with a head 3c. The drive screw may be adjusted manually or using a power tool such as a handheld power drill. In Figure 9 the second portion 3b is relatively extended 20 compared to the position shown in Figure 8. To brace concrete formwork using the brace 1, a user may arrange the brace 1 adjacent the concrete formwork, with the bracket 3 facing the concrete formwork. Then the user may secure the base 2 to the ground or other underlying support (for example, using the 25 mounting features 12). Then the user may adjust one, or both of the first and second arms relative to the base 2 and the bracket 3, to adjust the orientation and/or position of the bracket relative to the base. The user may also adjust the height of the brace 3. The user may attach the bracket to formwork using screws or other fasteners, or using a quick release mechanism such as described below. In practice a plurality of braces will 30 generally be arranged to support a formwork. The user may fine tune the brace adjustments once two or more, or all, of the braces are in position.

11 Figure 10 shows a set of concrete formwork braces according to an embodiment of the present invention supporting formwork 15. Any number of braces 1 may be arranged in any suitable arrangement to support the concrete formwork. 5 Another aspect of the invention relates to a quick-release mechanism for readily attaching and detaching concrete formwork braces to formwork. Figures 11 - 20 show various releasable connection arrangements for connecting a 10 concrete formwork brace to concrete formwork. In each case the releasable connection arrangement includes a first engagement element 16 on the bracket 3, configured to engage with a cooperating second engagement element 17 on a concrete formwork 15 to define a releasable connection between the bracket 3 and the formwork 15. 15 Figures 11 - 18 shows different embodiments of the second engagement element 17 on concrete formwork 15. The releasable connection between the bracket 3 and the formwork 15 may be any suitable releasable connection, for example a releasable clamp connection or a releasable hook connection. A releasable connection is one where the bracket and the formwork can be readily engaged and disengaged from each 20 other without damage to formwork. Figure 11a shows an embodiment wherein the second engagement element 17 is a protrusion having a T-shaped profile. Figure 11 b shows a cross section of the second engagement element 17. The second engagement element 17 includes a narrow neck 25 19 and a wider head portion 20. The first engagement element 16 is a clamp element which in an engaged state is clamped around head portion 20 of second engagement element 17. An actuator 18 (in the shown embodiment, a lever), is toggled to clamp and unclamp the second engagement element 17. A base portion 21 of the second engagement element 17 holding the neck 19 and the head 20 is permanently attached 30 to the formwork 15.

12 Figure 12 shows an embodiment wherein the second engagement element 17 is attached to the formwork 15 by cutting a hole in the formwork (for example wooden formwork), and inserting the second engagement element 17. The second engagement element 17 is in this case a cylindrical bracket mount which protrudes from the 5 formwork. A suitable first engagement element (not shown) may be provided to engage with the second engagement element 17. Figure 12a is a side view showing the installed second engagement element 17 protruding from the surface of the formwork 15. 10 Figures 13a and 13b show an embodiment wherein the second engagement element 17 is mounted to the formwork 15 by insertion through a channel. For example, this may be custom metal extruded formwork 15 with a channel for sliding bracket mounts. The embodiment of Figure 13a may be suited to a second engagement element 17 having a cross section similar to that of Figure 11 b. Figure 13b shows a side view of the 15 formwork 15 of Figure 13a with the second engagement element positioned within the channel. The formwork 15 includes an opening 22. This opening is wide enough to admit the neck 19 of the second engagement element 17, however it is narrow than the base 21 of the second engagement element 17, such that the second engagement element 17 cannot escape through the opening 22. A channel is formed by lips 23 is 20 provided inside the formwork 15 of dimensions slightly greater than that of the base 21. Thus the base can slide within the channel. Figure 14 shows an embodiment wherein the second engagement element 17 is fixed directly to a formwork surface with screws or other suitable fasteners. The second 25 engagement element 17 may have a T-shaped profile similar to that of Figure 11 b, or it may have any other suitable shape that cooperates with a corresponding first engagement element 16. Figures 15-18 show further examples of second engagement elements 17 cooperating 30 with first engagement elements 16 to form a releasable connection.

13 Figure 15 shows an embodiment in which the first engagement element 16 is a cylindrical disk and the second engagement element 17 is a channel configured to receive the first engagement element 16. Unlike the embodiment of Figure 13, in which the channel was part of the formwork itself, in this embodiment the channel is 5 fastened to the formwork (not shown) and protrudes from it. The cylindrical disk or flange 16 may be slid into the channel from the top. Figure 16 shows an embodiment wherein the first engagement element 17 includes rectangular apertures 24, and the second engagement element 16 includes hooks 25 10 that hook into the apertures 24. The actuator 18 in this embodiment is a lever, which can be rotated to move the hooks 16 up or down, into or out of the apertures 24. Figure 17 shows an embodiment wherein the first engagement element 16 has a complimentary shape to the second engagement element 17. This embodiment may 15 provide a twist lock mechanism. The second engagement element 17 fits around the first engagement element 16 like a lock and key. The actuator can be twisted to lock the first engagement element 16 around the second engagement element 17. Preferably, in an engaged state the bracket 3 is flush against the formwork. Figure 18 20 shows an embodiment where this is the case. The second engagement element 17 includes a protrusion (T-shaped protrusion). The bracket 3 includes a recess which contains first engagement element 16. In an engaged state, the second engagement element 17 locates itself within the recess of the bracket 3. The bracket 3 is pulled towards formwork 15 in this configuration, such that it is flush against the formwork. 25 The concrete formwork brace 1 may include an actuator 18 to toggle the first engagement element 16 between an engaged state and an unengaged state. The actuator 18 may be a lever, a handle, knob, button or any other suitable actuator. 30 Figure 19 shows a further embodiment wherein the actuator 18 is a lever. The lever 18 is pulled downwards, as shown by arrow D to release the bracket 3 from formwork 15.

14 Figures 15-18 show other embodiments including an actuator 18 to toggle between an engaged and unengaged state of connection. The actuator 18 may also be readily removable from the bracket. This may be useful, for example, to prevent tampering with the bracket when it is left unattended. 5 The second engagement element may act as a spacer when formwork is arranged in stacks (e.g. for transportation or storage). This increases airflow between the formwork members allowing faster drying after use and reduced distortion/warping of the formwork. Figure 20 shows stacked formwork 15 including second engagement 10 elements 17 creating spaces between formworks 15. The invention facilitates removal of bracing from formwork in a non-disruptive manner which does not affect the concrete. The result is that bracing can be removed from formwork much sooner than under traditional bracing methods. This saves construction 15 time and cost. In some applications it is expected that the bracing could be removed from the formwork the same day as concrete is poured. The concrete formwork brace of the present invention, when equipped with a suitable connector, does not damage formwork each time it is attached to and detached from 20 formwork. It is highly reusable, and saves on materials and cost. The brace of the present invention can be readily adjusted both manually and using automated power tools. The adjustment is quick and simple, and can be made before or after the brace has been secured to the formwork. 25 There is thus provided a concrete formwork brace which is sturdy and readily adjustable to accommodate different required heights and/or orientations. The quadrilateral geometry of the brace provides rigidity ensuring that formwork is kept in place. The brace is quick, easy and convenient to set up. Angular and height 30 adjustments can be made with ease.

15 The four pivot points of adjustment allow angular and height adjustments of the bracket to be made with extreme precision. This arrangement also allows the brace to be used on sloping surfaces. 5 There is provided a brace which can be quickly secured to and detached from formwork, using a quick release mechanism. This improves the efficiency of completing the concrete forming as users can quickly set up the braces and move them from formwork to formwork. 10 While the present invention has been illustrated by the description of the embodiments thereof, and while the embodiments have been described in detail, it is not the intention of the Applicant to restrict or in any way limit the scope of the appended claims to such detail. Further, the above embodiments may be implemented individually, or may be combined where compatible. Additional advantages and 15 modifications, including combinations of the above embodiments, will readily appear to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, representative apparatus and methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departure from the spirit or scope of the Applicant's general inventive concept.

Claims

1. A concrete formwork brace including: a base, 5 a bracket configured to support a concrete formwork, a first length adjustable arm, connected to the base and the bracket, and a second arm connected to the base and the bracket; wherein the connection between the first arm and the base is vertically offset from the connection between the second arm and the base, 10 wherein the connection between the first arm and the bracket is vertically offset from the connection between the second arm and the bracket; and wherein the first arm is length adjustable such as to adjust the orientation of the bracket. 15

2. The concrete formwork brace of claim 1, wherein the second arm is length adjustable.

3. The concrete formwork brace of any one of the preceding claims wherein the connection between the first arm and the base is horizontally offset from the 20 connection between the second arm and the base.

4. The concrete formwork brace of any one of the preceding claims wherein the connection between the first arm and the base is at a first end of the base and the connection between the second arm and the base is at an intermediate position 25 between the first end of the base and a second end of the base.

5. The concrete formwork brace of claim 4 wherein the connection between the second arm and the base is centrally located on the base. 17

6. The concrete formwork brace of any one of the preceding claims wherein the connection between the second arm and the base is vertically elevated relative to the connection between the first arm and the base. 5

7. The concrete formwork brace of any one of the preceding claims wherein the base has mounting features for securing the base to a ground surface.

8. The concrete formwork brace of claim 7 wherein the mounting features are apertures configured to receive fasteners for securing the base to a ground surface. 10

9. The concrete formwork brace of any one of the preceding claims wherein the bracket has mounting features for securing the bracket to formwork.

10. The concrete formwork brace of claim 9 wherein the bracket has apertures 15 configured to receive fasteners securing the bracket to formwork

11. The concrete formwork brace of any one of the preceding claims wherein the bracket is configured to rest, in use, on a ground surface. 20

12. The concrete formwork brace of any one of the preceding claims wherein the bracket is height-adjustable.

13. The concrete formwork brace of any one of the preceding claims wherein the brace includes a level indicator. 25

14. The concrete formwork brace of any one of the preceding claims, wherein the first length adjustable arm is length-adjustable by rotation of a threaded element.

15. The concrete formwork brace of claim 2, or any one of claims 3-14 when 30 dependent on claim 2, wherein the second arm is length-adjustable by rotation of a threaded element. 18

16. The concrete formwork brace of any one of the preceding claims wherein the connection between the first arm and the bracket is a pivotal connection and the connection between the second arm and the bracket is a pivotal connection. 5

17. The concrete formwork brace of any one of the preceding claims wherein the connection between the first arm and the base is a pivotal connection and the connection between the second arm and the base is a pivotal connection. 10

18. A method of bracing a concrete formwork using a concrete formwork brace as claimed in any one of the preceding claims, the method including the steps of: arranging the concrete formwork brace adjacent the concrete formwork, with the bracket facing the concrete formwork, securing the base to the ground or other underlying support; 15 adjusting one or more of the first and second arms relative to the base and the bracket, to adjust the orientation and/or position of the bracket.

19. A concrete formwork brace including: a base; and 20 a bracket supported by the base, the bracket including: a first engagement element configured to engage with a cooperating second engagement element on a concrete formwork to define a releasable connection between the bracket and the formwork. 25

20. The concrete formwork brace of claim 19 wherein the releasable connection is a clamp connection.

21. The concrete formwork brace of any one of claims 19-20 wherein the releasable 30 connection is a hook connection. 19

22. The concrete formwork brace of any one of claims 19-21 wherein, in use, in an engaged state the bracket is flush against the formwork.

23. The concrete formwork brace of any one of claims 19-22 wherein the second 5 engagement element includes a protrusion.

24. The concrete formwork brace of claim 23 wherein the protrusion is located in a recess of the bracket when the bracket and the formwork are connected. 10

25. The concrete formwork brace of any one of claims 19-24 including an actuator to toggle the first engagement element between an engaged state and an unengaged state.

26. The concrete formwork brace of claim 25 wherein the actuator is a lever. 15

27. The concrete formwork brace of claim 25 wherein the actuator is a latch.

28. The concrete formwork brace of claim 25 wherein the actuator is a twist lock actuator. 20

29. The concrete formwork brace of claim 25 wherein the actuator is removable from the bracket.

30. The concrete formwork brace of any one of claims 19-29 wherein the formwork is 25 wooden.

31. The concrete formwork brace of any one of claims 19-30 wherein the formwork is metal. 30

32. The concrete formwork brace any one of claims 19 - 31 wherein the second engagement element is inserted into a channel in the formwork. 20

33. The concrete formwork brace of any one of claims 19 - 32 wherein the second engagement element acts as a spacer when formwork is arranged in stacks. 5

34. A method of releasably engaging formwork to a concrete formwork brace as claimed in any one of claims 19 - 33, the method including the steps of: creating or securing a second engagement element on the formwork, arranging the concrete formwork brace adjacent the formwork, with the bracket facing the concrete formwork, and ; 10 engaging the first engagement element with the second engagement element.

35. A concrete formwork system including: one or more concrete formwork braces as claimed in any one of claims 19-33; and 15 concrete formwork including one or more second engagement elements configured to cooperate with one of the first engagement elements.

36. Concrete formed by the method of claim 18 or claim 34. 20