Formwork panel assembly with releasable connecting member and method of removing the formwork

Abstract

This disclosure relates to a formwork panel assembly to mold upwardly extending building features such as columns or walls, that extend between adjacent floor slabs. In one aspect, the formwork panel assembly comprises at least two surface forming elements, and at least one connecting element adapted for removable location between the two surface forming elements, where adjacent edges of the surface forming elements abut against the connecting element so that the resulting formwork assembly forms a single, continuous casting surface, and wherein in use, the or each connecting element is separately releasable from the formwork assembly once a concrete surface has been formed.

Claims

1. A formwork assembly for moulding an upwardly extending building feature, the formwork assembly comprising: at least two surface forming elements for forming a side of said building feature; and a removable connecting element positioned between the two surface forming elements, wherein each forming element comprises a rectilinear frame, a planar board member and a border extending about a perimeter of the board and beyond a pair of opposing edges of the frame to form a pair of flanges, wherein the connecting element comprises a cap for location between the flanges of adjacent surface forming elements, a cover plate, and a body between the cap and the cover plate which is shaped to substantially fill the void behind the flanges and between the frames of the forming elements, and wherein in use, adjacent flanges of the surface forming elements abut against the cap of the connecting element such that the resulting formwork assembly forms a single, continuous casting surface, and the cover plate of the connecting element extends behind the two surface forming elements, and the connecting element is separately releasable from the formwork assembly once a concrete surface has been formed.

2. The formwork assembly of claim 1, wherein the connecting element is so sized and shaped as to create, via removal of the connecting element, a space between adjacent surface forming elements sufficient to provide access or clearance to pry the surface forming elements away from the concrete surface.

3. The formwork assembly of claim 2, wherein for each surface forming element the rectilinear frame is secured to one side of a planar board member, and wherein, in use, the other side of the planar board member forms at least a part of the continuous casting surface.

4. The formwork assembly of claim 1, wherein for each surface forming element the border forms the continuous casting surface along with the planar board member.

5. The formwork assembly of claim 4, wherein the border is made of a material with greater wear resistance than the material of the planar board member.

6. The formwork assembly of claim 1, wherein the connection element is an elongate element comprising a cross-sectional shape which is substantially constant throughout a length of the elongate element.

7. The formwork assembly of claim 6, wherein the connection element is formed by extrusion.

8. The formwork assembly of claim 1, further comprising at least one of dowels and bolts configured to extend through aligned holes in a pair of adjacent surface forming elements, and the cover plate of their respective connecting element, to secure the adjacent surface forming elements and the corresponding connecting element together.

9. A method for moulding an upwardly extending building feature using a formwork assembly comprising at least two surface forming elements for forming a side of said building feature, and a removable connecting element positioned between the two surface forming elements, wherein each forming element comprises a rectilinear frame, a planar board member and a border extending about a perimeter of the board and beyond a pair of opposing edges of the frame to form a pair of flanges, wherein the connecting element comprises a cap for location between the flanges of adjacent surface forming elements, a cover plate, and a body between the cap and the cover plate which is shaped to substantially fill the void behind the flanges and between the frames of the forming elements, and wherein in use adjacent flanges of the surface forming elements abut against the cap of the connecting element such that the resulting formwork assembly forms a single, continuous casting surface, the method comprising: moulding the upwardly extending building feature using the formwork assembly; and then, when the concrete has cured sufficiently, removing the connecting element to create a space between adjacent surface forming elements, wherein the pace provides sufficient access to pry the surface forming elements away from the concrete surface.

10. The formwork assembly of claim 1, wherein the connecting element comprises a number of apertures extending through each of the cap, the body and the cover plate thereof, spaced apart along its length.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) Embodiments of the present invention will be discussed with reference to the accompanying drawings wherein:

(2) FIG. 1 illustrates a formwork panel assembly according to a first embodiment;

(3) FIG. 1a is an end view of the formwork panel assembly of FIG. 1;

(4) FIG. 1b is a detail view taken from FIG. 1a;

(5) FIG. 2 illustrates a surface forming element from the formwork panel assembly of FIG. 1;

(6) FIG. 2a is a side view of the surface forming element of FIG. 2;

(7) FIG. 2b is an end view of the surface forming element of FIG. 2;

(8) FIG. 2c is detail view taken from FIG. 2b;

(9) FIG. 3 illustrates a connecting element from the formwork panel assembly of FIG. 1;

(10) FIG. 3a is plan view of the connecting element of FIG. 3;

(11) FIG. 3b is a side view of the connecting element of FIG. 3;

(12) FIG. 4 illustrates a portion of an end section of a formwork panel assembly, showing connecting pins, panel ties and an end formwork bracing assembly;

(13) FIG. 5 illustrates a formwork panel assembly according to a second embodiment;

(14) FIG. 5a is an end view of the formwork panel assembly of FIG. 5;

(15) FIG. 6 is a plan view of a surface forming element from the formwork panel assembly of FIG. 5;

(16) FIG. 6a is a side view of the surface forming element of FIG. 6;

(17) FIG. 6b is an end view of the formwork panel assembly of FIG. 6;

(18) FIG. 7 is an end view of a connecting element from the formwork panel assembly of FIG. 5;

(19) FIG. 7a is a plan view of the connecting element of FIG. 7; and

(20) FIG. 8 is a plan view of a further surface forming element from the formwork panel assembly of FIG. 5.

(21) In the following description, like reference characters designate like or corresponding parts throughout the figures.

DESCRIPTION OF EMBODIMENTS

(22) FIG. 1 illustrates a formwork panel assembly 10 according to an embodiment. The formwork panel assembly 10 comprises three surface forming elements 11, and two connecting elements 12, although more or less of each of the formwork panel assemblies 10, and surface forming elements 11 may be used as required. The connecting elements 12 are located between a pair of adjacent edges of surface forming elements 11. As can be seen in FIG. 1a, the formwork panel assembly 10 comprises a planar surface 17a against which concrete can be moulded.

(23) Referring now to FIGS. 2 through 2c, where there is illustrated one of the surface forming elements 11 from the formwork panel assembly 10. The surface forming element 11 comprises a frame 14 constructed from steel tubes of square cross-sectional shape. Each frame 14 comprises a pair of horizontal members 15 and a number of vertical members 16 welded at each end between the horizontal members 15.

(24) The frame 14 is generally rectangular in shape and has attached to it a board 17. In this embodiment, the board 17 is made of a material such as plywood, having a thickness of approximately 12 millimetres, which forms part of the planar surface 17a.

(25) The frame 14 further comprises a border 50 extending about a perimeter of the board 17. This border 50 is comprised of a plurality of flat strips 52 of a material (being namely flat steel bar welded to the frame 14 in this embodiment) of a matching thickness to the board 17, but more wear resistant than the material of the board 17, where one strip 52 extends along each of the horizontal members 15, and the vertical members 16 which define the ends 20 and 21 of the frame 14. With reference to FIG. 2c, it can be seen that the border 50 extends past the edge of the frame 14 by approximately 10 millimetres along the upper and lower edges 18 and 19. In contrast, the border 50 is flush with the ends 20 and 21 of the frame 14.

(26) The horizontal members 15 of the frame 14 comprise pairs of apertures 24 for the location of retaining dowels, as will be explained in further detail below.

(27) FIG. 3 shows a connecting element 12 from the formwork panel assembly 10, which, in this embodiment, comprises a length of square steel tubing 25, being 50 mm square, and having attached to it on one side a cap 26 comprising an elongate length of steel strip being 12 millimetres thick and approximately 30 millimetres wide. This leaves a clearance of approximately 10 millimetres on either side of the cap 26, being from the edge of the cap 26 to the edge of the steel tubing 25.

(28) On the other side of the steel tubing 25, there is a cover plate 27 having a thickness of 6 millimetres but a width of 100 millimetres.

(29) The square steel tubing 25 has a number of apertures along its length. Firstly, it has a pair of apertures 28 at either end. At 90 degrees to the apertures 28, there are a number of apertures 29 spaced along the steel tube 25 that extend through each of the square steel tubing 25 and the cap and cover plate 26, 27.

(30) As can be seen from FIG. 1, in use, the connecting elements 12 are placed between adjacent surface forming elements 11. Each of the upper and lower edges 18 and 19 of the surface forming elements 11 abuts against the square steel tubing 25 of the connecting element 12, with the edges of the border 50 on the surface forming element 11 abutting against either side of the cap 26. With reference to FIGS. 1a and 1b, it can be seen that the edges of the border 50 therefore overlap (by ten millimetres) the square steel tubing 25.

(31) Being made of a harder, more wear resistant material than that of the board 17, means that the border 50, which extends beyond the edges of the frame 14, is less susceptible to damage resulting from normal handling and positioning of surface forming elements 11, than would be the board 17 if this extended beyond the edge of the frame 14 in this fashion.

(32) On the other side of the connecting element 12, the cover plate 27 extends over a portion of the horizontal member 15 of the upper and lower frame 14.

(33) In this way, overlapping joints are formed that prevent egress of concrete while at the same time providing a smooth and flush moulding surface 17a, when the surface forming elements 11 and connecting elements 12 are assembled.

(34) As can be seen in FIG. 4, the pairs of apertures 24 in the horizontal member 15 of the frame 14 align with the pairs of apertures 28 in the connecting element 12. This enables dowels 30 to be inserted through both apertures 24 and 28 to secure an upper and a lower surface forming element 11 with respect to a connecting element 12. The dowels 30 may be threaded (such as by use of z-tie threads) to clamp the components together.

(35) FIG. 4 also shows horizontal ties 31 that extend between adjacent formwork panel assemblies 10. The horizontal tie 31 locates in apertures 29. These horizontal ties also comprise z-tie rods, and resist the weight of the concrete pushing the adjacent formwork panel assemblies 10 apart. A number of horizontal ties 31 can be located in the apertures 29 along the length of the connecting element 12.

(36) FIG. 4 also shows end braces which are used to hold formwork located between and opposite the opposed or adjacent formwork panel assemblies 10. As seen in FIG. 4, the formwork panel assemblies 10 are being used to create an elongate wall and therefore are only spaced apart by approximately 300 to 400 millimetres. Accordingly, formwork (not shown) can be placed between this gap at each end to form the end of the walls between the formwork panel assemblies 10. That formwork is held in place during pouring of the concrete by bracing bars 33.

(37) The bracing bar 33 slides within the square steel tubing used to form the horizontal member 15 of a surface forming element 11. A bracing bar 33 has an aperture in one end through which the dowel 30 locates thereby holding the bracing bar 33 firmly with respect to the horizontal member 15.

(38) At the other end of the bracing bar 33 there is a z-tie rod 34 secured to and extending out of the end of the bracing bar 33. Plates 35 are used to clamp cross bars 36 between adjacent bracing bars 33 that are connected to each of the surface forming elements 11. A pair of bracing bars 33 are used at the same level on adjacent surface forming elements 11. Therefore, the plates 35 can be used to clamp cross bars 36 between adjacent bracing bars 33. The plates 35 have apertures through which the z-tie rods 34 locate which then enable the cross bars 36 to be clamped with respect to the bracing bars 33. Braces 37 are then located between the cross bars 36 and a formwork that is located between the adjacent formwork panel assemblies 10. In this matter, a convenient way is provided to brace the end formwork extending between adjacent formwork panel assemblies 10, against outward movement.

(39) It would also be possible to have apertures through the end vertical bars 16 on the surface forming elements 11. These apertures would both be normal with respect to the surface forming element 11 and parallel to it. This would enable adjacent edges to be abutted and secured using dowels 30. This process may be used in the case of forming columns where the length of the surface forming elements 11 are reasonably short and it is more convenient to join the formwork panel assemblies 10 at adjoining edges where a square or rectangular cross-section column is being manufactured.

(40) As will be seen from the above description, the formwork panel assembly 10 can be easily assembled so as to put in place formwork which can mould vertical building features between floor slabs. Once the formwork panel assemblies 10 are in place, the formwork forming the underside surface of the upper floor can abut against the upper edge of the formwork panel assembly 10.

(41) Of course, this would result in the formwork panel assembly 10 being wedged between the upper surface of the lower floor slab and the underside surface of the upper floor slab once the surrounding formwork forming the underside surface of the upper floor slab is removed. However, the connecting elements 12 can be easily removed from the formwork panel assembly 10 from the outside. This then provides access for levering off the individual surface forming elements 11 from the moulded concrete surface. It will be readily apparent that this invention provides a means of removing formwork which would otherwise be wedged between a lower and upper surface between floor slabs.

(42) Referring now to FIGS. 5 through 7a, where there is illustrated a formwork panel assembly 100 according to a further embodiment. Those parts of the formwork panel assembly 100 which are identical (or near identical) to corresponding parts shown in the formwork panel assembly 10, will be denoted by the same reference numerals and will not be described again in detail.

(43) The formwork panel assembly 100 comprises three surface forming elements 111 (of two sizes, namely IIIa and IIIb) and four connecting elements 112. The connecting elements 112 are located between a pair of adjacent edges of surface forming elements 111. As can be seen in FIG. 5a, the formwork panel assembly 100 comprises a planar surface 17a against which concrete can be moulded.

(44) The surface forming elements 111 differ from those of the previous embodiment in that each comprises a frame 114 of square aluminium tubing (as opposed to square steel tubing). This aluminium tubing makes the surface forming elements 111 considerably lighter than those of the previous embodiment.

(45) The frame for the or each surface forming element 111 comprises a plurality of perimeter frame members 15 and 16a, and a portion of the border 50 depends from each perimeter frame member 15 and 16a. In this embodiment, each perimeter frame member 15 and 16a, and its respective portion of the border 50, are extruded together (as opposed to fabricated).

(46) Moreover, the connecting elements 112 differ from those of the previous embodiment in that each comprises a sectional shape similar to that of connection element 12, but which is extruded (as opposed to fabricated) from aluminium (as opposed to steel). This use of aluminium tubing makes the connecting elements 112 considerably lighter than those of the previous embodiment. Moreover, manufacture by extrusion is considerably less labour intensive, and therefore cheaper, than manufacture by fabrication.

(47) Therefore, in one aspect of this invention, the invention allows formwork creating a vertical surface between floor slabs to be put in place currently with the upper slab formwork and for it to be removable once the concrete of the upper slab is set and cured.

(48) Throughout the specification and the claims that follow, unless the context requires otherwise, the words comprise and include and variations such as comprising and including will be understood to imply the inclusion of a stated integer or group of integers, but not the exclusion of any other integer or group of integers.

(49) The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that such prior art forms part of the common general knowledge.

(50) It will be appreciated by those skilled in the art that the invention is not restricted in its use to the particular application described. Neither is the present invention restricted in its preferred embodiment with regard to the particular elements and/or features described or depicted herein. It will be appreciated that the invention is not limited to the embodiment or embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the scope of the invention as set forth and defined by the following claims.