WO2005021892A1

WO2005021892A1 - A shuttering element

Info

Publication number: WO2005021892A1
Application number: PCT/IB2004/002793
Authority: WO
Inventors: Mark Charles Gardner Lindner
Original assignee: Mark Charles Gardner Lindner
Priority date: 2003-08-28
Filing date: 2004-08-30
Publication date: 2005-03-10
Also published as: ZA200306715B

Abstract

A shuttering element moulded from a plastics material is provided which includes a rectangular panel with a skirt extending therefrom at least partway around the periphery thereof. The skirt along each of an adjacent pair of sides of the panel has a channel section complementary to a lip on the skirt opposite thereto.

Description

A SHUTTERING ELEMENT

FIELD OF THE INVENTION

This invention relates to a shuttering element, more particularly, but not exclusively, to a shuttering element for use in the construction industry.

BACKGROUND TO THE INVENTION

Shuttering is widely used in the construction of buildings to shape wet concrete and typically is formed by a plurality of steel or plastics panels secured end to end. These panels are usually rectangular with a flange extending around the periphery which enables panels to be secured side-by-side.

Although effective, such panels, particularly steel panels, are fairly expensive to manufacture and are frequently damaged by rough handling. Such damage includes deformation of the peripheral flange which often results in the panels becoming unusable. Also, it is common for wet cement to leak from between adjacent flanges.

OBJECT OF THE INVENTION It is an object of this invention to provide a shuttering element which will at least partially alleviate some of the abovementioned problems. SUMMARY OF THE INVENTION

In accordance with this invention there is provided a shuttering element comprising a rectangular panel with a skirt extending therefrom at least partway around the periphery thereof, with the skirt along each of an adjacent pair of sides of the panel having a channel section complementary to a lip on the skirt opposite thereto.

Further features of the invention provide for the edge of the panel to be recessed along each of a pair of adjacent sides, preferably the sides adjacent the channel sections; for a tongue to extend from the edges of the panel opposite each recess; for the skirt to extend the length of each side of the panel; for each channel section to extend at least partway along the length of its corresponding side; for each channel section to extend integrally from the skirt; for each lip to extend integrally from the skirt; and for there to be a number of oppositely aligned apertures extending through the skirt.

Still further features of the invention provide for at least parts of the channel section to extend towards the panel and for the extended channel sections to be engageable with the skirt of an oppositely disposed shuttering element.

Yet further features of the invention provide for the shuttering element to be moulded from a plastics material; and for strengthening elements to extend across the panel within the skirt.

The invention also provides a shuttering element moulded from a plastics material and characterised in that it has interlocking formations which are operatively securable to complementary formations on adjacent elements. BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described, by way of example only, with reference to the drawings in which:

Figure 1 is a top perspective view of a first embodiment of a shuttering element; Figure 2 is a bottom perspective view of the shuttering element in Figure 1 ; Figure 3 is a sectional side elevation of the shuttering element in Figure 1 ; Figure 4 is a sectional side elevation of a part of a pair of shuttering element is secured side to side; Figure 5 is a bottom perspective view of a second embodiment of a shuttering element; and Figure 6 is a bottom perspective view of a third embodiment of a shuttering element;

Figure 7 is a top perspective view showing locking formations for the securing abutting skirts of contiguous panels together; Figure 8 is a detail of the locked formations; and Figure 9 is a bottom perspective of two panels secured together.

DETAILED DESCRIPTION OF THE DRAWINGS

A shuttering element (1) moulded from a plastics material is shown in Figures 1 to 3 and includes a rectangular, in this embodiment square, panel (2) with a skirt (4) extending normally therefrom about its periphery. The skirt (4) thus forms four corners (5).

The skirt along a pair of adjacent sides (6,7) has a channel section (8,9) extending integrally therefrom opposite the skirt (4). The channel sections (8,9) are outwardly directed and extend from the skirt (4) from near the corners (5). A co-planar lip (12,13) extends integrally from the skirt opposite each channel section (8,9). The lips (12,13) extend along the skirt (4) from near the corners (5a, 5b) adjacent the channel sections (8,9) to the opposite corner (5c) where they are joined.

The edges of the panel (2) adjacent the sides (6,7) have recesses (15) therein while a complementarily shaped tongue (17) extends from the edges of the opposite sides (19, 20).

A series of oppositely aligned apertures (25) are formed in the skirt (4), evenly spaced between the corners (5).

Strengthening elements (30) extend across the panel (2) within the skirt (4). These have the form of intersecting flanges extending normally from the skirt (4) in a manner well-known to those skilled in the manufacture of plastics goods.

In use, a plurality of shuttering elements are arranged side-by-side with each lip nested within an adjacent channel section and a tongue (17) seated in a recess (15), as shown in Figure 4. In this condition the apertures (25) along each side of adjacent skirts are aligned and can receive a fastener (40), in this embodiment a bolt, therethrough. This permits easy assembly of a formwork while the configuration of the tongue and recess and lip and channel section substantially eliminate the possibility of leakage between adjacent skirts.

Furthermore, as the shuttering element is moulded from a durable plastics material, preferably polypropylene or high density polyethylene (HDPE), it is highly resistant to deformation and can be cheaply manufactured. It has been found that the shuttering elements are able to be used up to approximately 100 times without any maintenance, unlike the steel units which are maintained on a regular basis. Also, as concrete does not stick to the panels they can be easily cleaned and leave a smooth finish to cast concrete structures.

It will be appreciated, however, that many other embodiments of a shuttering element exist which fall within the scope of the invention, particularly as regards the configuration thereof. For example, as shown in Figures 5 and 6 the shuttering element (60, 70) could have adjacent sides of unequal length. Also, the skirt, channel sections and lips to be interrupted in their length and a tongue and recess need not be provided in the panel.

Also, it is not necessary to use bolts to secure the shuttering elements together and any suitable fastener can be used. The configuration of the shuttering elements makes it possible to reduce the number of fasteners needed or to completely avoid the use of fasteners in certain circumstances. It has been found that the panels can be glued together using PVC solvent where the panels are made from HDPE. This is useful where the panels are used to construct a large number of identical buildings, such as in low cost housing developments. Whole sections of formwork can then simply be moved from site to site as required, further simplifying the construction process.

Importantly, any suitable interlocking formation can be used on the shuttering elements enabling them to be secured end to end. These formations include dove tail, T tail and key-hole formations.

Figures 7 to 9 show an alternative embodiment of the invention. In particular, the channel sections (8, 9) of the shutter element (80) extend towards the panel (2) in sections (81 , 82). The extended sections (81, 82) are configured to capture the skirt (83) of an adjacent element (84). In addition, the skirt of the element (80) is provided with two L-shaped slots (85, 86) in each of its four sides. The slots on a channelled side of an element align with slots on a lipped side of another member allowing two adjacent elements to be secured to each other with a key (87). The key-slot assembly provides additional strengthening of the connections between two adjacent elements.

It is to be noted that the key-slots also pass through the extended sections 81, 82 of the channel sections. The keys (87) for locking contiguous panels together consist of brackets (100) on the ends of a rigid bar (101). The brackets carry rods (not shown) which engage the L-shaped slots and clamp abutting skirts together. The bar (101) also carries a manipulating handle (102) projecting on the opposite to the brackets (100).

Also illustrated in Fig. 9 are hollow cylindrical components (103) which form part of the strengthening elements (30). The components (103) may accommodate expandable plugs (104) with handles (105). These plugs and handles facilitate the manipulation of the panels.

From the above it will be appreciated that the shuttering panels are versatile and simple to erect and dismantle which also reduces damage and general wear and tear during use.

Claims

1. A shuttering element (1) comprising a rectangular panel (2) with a skirt (4) extending therefrom at least partway around the periphery thereof, characterised in that the skirt (4) along each of an adjacent pair of sides (6, 7) of the panel (2) has a channel section (8, 9) complementary to a lip (12, 13) on the skirt (4) opposite thereto.

2. A shuttering element as claimed in claim 1 characterised in that the edge of the panel (2) is recessed along each of a pair of adjacent sides.

3. A shuttering element as claimed in claim 2 characterised in that the sides having the recessed edges are adjacent the channel sections (8, 9).

4. A shuttering element as claimed in claim 2 or claim 3 characterised in that a tongue extends from the edges of the panel (2) opposite the recessed edges.

5. A shuttering element as claimed in any one of the preceding claims characterised in that the skirt (4) extends along the length of each side of the panel (2).

6. A shuttering element as claimed in any one of the preceding claims characterised in that each channel section (8, 9) extends partway along the length of its corresponding side.

7. A shuttering element as claimed in any one of the preceding claims characterised in that each channel section (8, 9) extends integrally from the skirt (4).

8. A shuttering element as claimed in any one of the preceding claims characterised in that each lip (12, 13) extends integrally from the skirt (4).

9. A shuttering element as claimed in any one of the preceding claims characterised in that a number of oppositely aligned apertures (25) extend through the skirt (4).

10. A shuttering element as claimed in any one of the preceding claims characterised in that at least part of the channel section (8, 9) extends towards the panel (2).

11. A shuttering element as claimed in claim 10 characterised in that the extended section (81 , 82) is engageable with the skirt (4) of an oppositely disposed shuttering element.

12. A shuttering element as claimed in any one of the preceding claims characterised it is moulded from a plastics material.

13. A shuttering element as claimed in claim 1 characterised in that strengthening elements extend across the panel (2) within the skirt (4).

14. A shuttering element moulded from a plastics material as claimed in claim 1 and characterised in that it has key operated interlocking formations (4) (81) which are operatively securable to complementary formations on adjacent elements.

15. A shuttering element substantially as described with reference to Figs 1 to 5 or Fig. 9 of the drawings.