Building component

Abstract
A method of constructing a wall of a building by casting in which formwork is erected and concrete is allowed to exude through perforations in the formwork, embedding the formwork in concrete and obscuring it from view. A panel for carrying out the method, a thin-walled sheet with multiple perforations for the escape of the concrete during casting, has brackets or clips to fasten it to the adjacent formwork creating a casting space between the panel and the supporting formwork. Floating the expressed concrete produces a smooth finish.
Description
FIELD OF THE INVENTION

This invention concerns a method of constructing walls, moulds for the same and buildings when constructed with such walls.


BACKGROUND OF THE INVENTION

The use of shuttering and formwork to create moulds for concrete buildings includes the step of removing the moulds so that the surface of the concrete is exposed and the mould is reusable. Recovering of the moulds imposes upon the builder the need to dismantle the formwork and to accept the surface finish left by the mould. It could be coloured and/or rendered, but the technique is thereby limited.


SUMMARY OF THE INVENTION

One apparatus aspect of the invention provides a wall of a building comprising courses of repeating spacer elements, the spacer elements together defining a core, a panel mould lying adjacent the face of the spacer, the space between the face of the spacer, and the wall of the mould being intended for filling with a fluent hardenable construction mix, the panel wall being perforated to permit the fluent mix to extrude and form a hardened layer outside the panel wall obscuring it from view.


The spacers may be closed at top and bottom and both ends, all the faces being impervious and resembling a closed box. The spacers may have means to support a lattice of reinforcement, such as rods. Full and half spacers may be provided to permit bonded courses to be built. When the spacers are assembled to form a matrix, they define multiple passages connecting the inner array of moulds with the outer array of moulds which fill with mix during construction and permanently join the two cast leaves of the wall.


The panels may include spaces whose edges define the openings of the wall, eg. doors and windows. The spacers may be hollow like a matrix of boxes. Alternatively, the spacers may be solid. Expanded polymer bead products, such as polystyrene bead material and closed cell foams are useful. The panels may be moulded, thermoformed or pressed from metal sheet.


The inner panel faces may be contoured so that the expressed mix forms covings and skirtings and other internal features of the building. The spacers may have ends which when assembled in courses, define the multiple passages connecting the outer array of panels with the inner array of panels. The term ‘panel’ is not restricted to a two dimensional structure which produces a planar wall. Curvilinear shapes are possible by manufacturing the panel in the required shape.


The outer face of the panel, that is the face defining the perimeter of the wall, namely the outside face and the inner face of the panel which defines the inner face of the building, are perforated and may also be corrugated or dimpled or otherwise arranged to accommodate different depths of mix in order to improve the float response of the wall.


Conventional reinforcement, such as required by building regulations, is included in the wall, for example rods and bars which are wired, welded or clipped together. The term ‘perforations’ includes slots. Circular perforations are useful. The diameter is not critical in that the quantity of mix which flows through the perforations depends on the composition of the mix, for example the aggregate size and the water content. Diameter of 5-15 mm have given useful results.


The corrugations on the panel are not essential in that acceptable results are attainable using flat panels, however the floating operation tends to push aggregate with the floor of corrugation and a smoother finish is achieved.




BRIEF DESCRIPTION OF THE DRAWINGS


FIG. 1 is a perspective view of a representative wall portion part way through construction.



FIG. 2 is an enlargement of the area marked A of FIG. 1 seen from direction B.



FIG. 3 is an exploded view of the wall portion shown in FIG. 1 with a pair of opposed panels.



FIG. 4 is a close up of an edge fragment of a panel showing the peg locator.



FIG. 5 is a close up of the corresponding edge portion of an adjacent panel showing the eye which receives the peg.



FIG. 6 is a perspective as in FIG. 1, showing part of the wall after casting.



FIG. 7 is a section through the completed wall.



FIG. 8 is a perspective of a wall containing a window with the moulds for the window surround propped in position for casting.



FIG. 9 is a section of the mould in FIG. 8.



FIG. 10 is a perspective of a fragment of a wall showing part conventional construction using casting panels.




DETAILED DESCRIPTION WITH RESPECT TO THE DRAWINGS

Referring to FIGS. 1, 2 and 3, a box-like spacer 2 is blow moulded from recycled plastic (600×300×65 mm). Each has a rectangular horizontal upper flange 4, a rectangular horizontal lower flange 6, a rectangular end flange 8 (one shown), an upstanding inner face 10 and an upstanding outer face 12. Accordingly the spacer is closed at the top and bottom and both ends.


The face 12 is impervious and together with adjoining spacers form a composite vertical mould face which cooperates with an array of panel moulds 14. The ribs 16 abut the spacer face 12. The ribs 16 of the panels have cradles 18 for supporting horizontal reinforcing rods 20. Vertical reinforcement rods 22 lie adjacent end ribs 24. Linking wires 26 join the rods associated with the inner panel 14 and the outer panel 28. The panels are injection mouldings with a sheet thickness of 1 mm.


Referring now to FIGS. 4 and 5, the exposed panel face 30 has corrugations 32 made up of flat crests 34, flat floors 36 and inclined margins 38. Rows of apertures 40 each 8 mm in diameter allow concrete to be expressed when the panel moulds are filled.


One end of each panel has a pair of pins 42 (one shown) and a pair of eyes 44 (one shown). The pins and eyes interengage and keep the panel array coplanar. Cradles 18 are more clearly seen and the bridges 46 which span a pair of ribs 16. The bridges together with the corrugated face 30 create guideways for the vertical bars 20.


The spacers are laid in courses with the bottom flange overlying the top flange of the course beneath. The spacers thus form a matrix in which the abutting ends form cylindrical passages 48 passing through the wall and interconnecting the inner and outer panel moulds. The spacers have a moulded vertical services tunnel 50 which registers with the tunnels in courses above and below. Service conduits ascend and descend in this way. Alternatively, there is room in the casting space. Apertures are cut in the panel to allow connection to service outlets in the room. In FIG. 6, the final cast appearance of the wall is shown. In FIG. 7, the wall is shown erected on a standard footing 52. All the spacers, moulds and reinforcements are embedded by the cast concrete.


In FIG. 8, the panels have mould extensions 54 fitted in two halves which allow the mix to form the headers, styles and sill of a window. These are fixed in the opening 56 by props 58. The mould in FIG. 9 is a split mould responsible for half the window edge profile. Mould extensions for interior features such as coving and skirtings are formed in like manner. A profiled float is used to follow the extension profile. Extension features, such as parapets cappings, column capitals and similar ornament are attainable.


In FIG. 10, slab 60 is a 2700×1200×75 mm aerated concrete slab sold under the trade mark HEBEL POWERPANEL. The panel 14 is extruded and then perforated with some perforations being vertically aligned to take thin rods 62.


The order of construction is as follows:


Footings are built conventionally with trench mesh, such that pairs of 1200 mm bars project at 220×600 spacings.


Initial courses of spacers 2 are then laid between the bars to a height of 1200 mm. Panels 14 are threaded on to the bars and slid down so that the ribs touch the spacers. The edges of the panels interfit. Horizontal bars are laid in the panel cradles and the vertical bars 22 are extended. The bars are wired together and linking wires 26 are inserted through the passages 48.


The next series of panels are threaded on the extended bars up to the first storey height of 2700 mm. Service conduits are inserted to mate with gaps inserted opposite the positions of outlets in the room of which the wall is a part. Water and electrical services are completed.


If the building is single storey, the structure is ready to pour. A concrete pump attends the site. The filler pipe of the concrete pump is bifurcated so as to direct flow into the casting spaces on both sides of the spacers. The building may be multistorey utilising the same methodology.


Concrete rises in the structure and flows into the passages, thereby joining the two leaves of the wall. As the weight of the concrete increases, the lower panels lose mix through the perforations. The panels express about 20 mm of concrete and floating operation commences. Once the float passes across the panel, the concrete loses it stippled appearance and expression ceases. The water content of the exterior changes and the smoothing operation can begin. The passages 48 through the wall thickness allow in situ bridges between the leaves of the wall and the moulds become entirely hidden by floated concrete. Any texturing or finishing process such as embedding grit now occurs. The pump then adds concrete on top to form the next storey. When the concrete dries, a colour such an acrylic coating is applied.


We have found the advantages of the above embodiments to be:

  • 1. The moulds remain in the structure permanently.
  • 2. Float material flows freely from the wall, obviating the need to apply render.
  • 3. Trade skill at a minor level suffices.
  • 4. Free forms, including curvilinear are attainable. Instead of or in addition to floating, patterning of devices can be present with the expressed concrete.


It is to be understood that the word “comprising” as used throughout the specification is to be interpreted in its inclusive form, ie. use of the word “comprising” does not exclude the addition of other elements.


It is to be understood that various modifications of and/or additions to the invention can be made without departing from the basic nature of the invention. These modifications and/or additions are therefore considered to fall within the scope of the invention.

Claims
  • 1. A method of constructing the wall of a building, comprising erecting formwork for shaping the wall by casting, pouring a fluent hardenable construction mix into the formwork allowing the mix to flow through the formwork embedding at least part of the formwork in the wall.
  • 2. A method as claimed in claim 1, including smoothing the mix which flows through the formwork by floating.
  • 3. A method as claimed in claim 1, including applying a finish to the mix by application of an embossing tool.
  • 4. A method as claimed in claim 1, including incorporating in the formwork the desired architectural profile and floating the mix with a float of corresponding profile.
  • 5. A method as claimed in claim 1, wherein half of the wall is constructed conventionally followed by erecting formwork adjacent the half of the wall is already constructed to create a casting space between the formwork and the constructed half, filling the casting space with fluent hardenable construction mix so that the formwork is embedded by hardened mix.
  • 6. A formwork panel for constructing a wall of a building by casting, comprising a thin-walled sheet with multiple perforations of the size which allow limited flow of fluent hardenable construction mix onto the exterior face of the sh casting, wherein expressed concrete embeds the sheet in the wall, the sheet having means to engage support elements of the formwork.
  • 7. A formwork panel as claimed in claim 6, wherein the means to engage support elements in the formwork are brackets extending from the interior face of the sheet capable of threading onto the reinforcing bar of the formwork.
  • 8. A formwork panel as claimed in claim 6, having multiple ribs extending from the interior face of the sheet in order to create a casting space inboard of the exterior face.
  • 9. A formwork panel as claimed in claim 6, wherein the sheet is of undulating section so as to create a layer of expressed mix of unequal depths.
  • 10. A formwork panel as claimed in claim 9, wherein the sheet is of zigzag section with some of the perforations being vertically aligned, whereby rods are threadable through the aligned perforations in order to support the sheet.
  • 11. A formwork panel as claimed in claim 9, wherein the means to engage the formwork are clips which extend through the perforations to engage the reinforcing bars.
  • 12. A wall of a building which comprises an array of courses of repeating spacer elements, the spacer elements together defining a core, wherein panel moulds are positioned adjacent each external composite face of the array, the casting space between the respective panel mould and the corresponding array being adapted to be filled with a fluent hardenable construction mix, each panel mould being perforated to permit the fluent mix to extrude and form a hardened layer outside the panel obscuring it from view.
  • 13. A wall as claimed in claim 12, wherein the spacer elements together define transverse passages which join the casting space adjacent one array of panels with the casting space adjacent the opposed array of panels and these passages fill with mix during construction.
  • 14. A wall as claimed in claim 13, wherein the spacer elements are substantially parallelepiped in shape with sockets capable of interconnecting each element with the next in the wall.
  • 15. A wall as claimed in claim 14, wherein the sockets engage by overlapping in order to ensure the courses are stable and self-supporting.
  • 16. A wall as claimed in claim 13, wherein the spacer elements have ends which, when assembled define the multiple passages connecting the outer array of panels with the inner array of panels.
  • 17. A wall as claimed in claim 12, wherein the spacer elements are solid and form an insulating core.
  • 18. A wall as claimed in claim 12, wherein the panel has a corrugated, dimpled or otherwise deformed in order to accommodate different depths of mix which exude through the multiple perforations.
  • 19. A wall as claimed claim 7, wherein each panel has integral supports for 10 supporting wall reinforcement bars.
  • 20. A wall as claimed in claim 8, wherein the corrugations have flat crests and flat floors joined by inclined margins.
  • 21. A wall as claimed in claim 8, wherein the perforations are distributed over the corrugations.
  • 22. A wall as claimed in claim 7, wherein the corrugations are 30-40 mm crest to crest.
  • 23. A wall as claimed in claim 7, wherein the perforations are 7-10 mm in diameter.
  • 24. A wall as claimed in claim 7, wherein the panels each have means to capture upright reinforcement bars.
  • 25. A wall as claimed in claim 13, wherein the bar capturing means comprises multiple vertical ribs which span the casting space between the elements and the perforated panel wall and at least two pairs of ribs are connected by a bridge which defines an aperture through which a rod is threadable.
  • 26. A wall as claimed in claim 7, wherein the panels each have connectors at their upright edges which permit mutual edge to edge connection of adjacent panels.
  • 27. A wall as claimed in claim 12, wherein the panel wall thickness is 1-3 mm.
  • 28. A wall as claimed in claim 12, wherein the panel is moulded from recycled plastic waste.
  • 29. A wall as claimed in claim 12, wherein an opening in the wall is lined with an unperforated mould which is connected to the panels so that the expressed mix conforms to the mould and forms headers, styles and sills for a door or window installation.
  • 30. A wall as claimed in claim 12, with conduits in the spacers for the provision of services.
  • 31 (canceled).
  • 32. A building containing a wall as claimed in claim 12.
Priority Claims (1)
Number Date Country Kind
PR 8756 Nov 2001 AU national
PCT Information
Filing Document Filing Date Country Kind
PCT/AU02/01507 11/4/2002 WO