GB2162560A - Swimming pool construction - Google Patents

Abstract

In order to provide an improved method of constructing a swimming pool wall by casting concrete into shuttering assembled on site from modular components, the shuttering is built up from elements comprising inner and outer slabs or blocks (11, 12) assembled together in a predetermined spaced relationship, and in which at least an external face of the shuttering is formed by the outer slabs which are of a thermally insulating foamed plastics material, preferably a high density polystyrene. The outer slabs are left in situ after pouring of the concrete to provide thermal insulation, while the inner slabs are removed after pouring and setting of the concrete, and may be disposed outside the outer slabs prior to back-filling the cavity outside the outer slabs. The slabs of each element are held together in spaced relationship by tie bars (13) of plastics material. Adjacent edges of the shuttering may have cooperating projections and recesses to allow angular movement without detriment to the seal between the edges. The invention also comprehends the shuttering itself. <IMAGE>

Description

SPECIFICATION Swimming pool construction This invention relates to the construction of swimming pools.

The now expired patent specifications GB-A-1038841, GB-A-1103981 and GB-A-1 103511 describe the use of shuttering elements comprising two slabs of cement joined together in spaced relationship by cast-in tie bars.

The shuttering elements are assembled together to form permanent shuttering for the construction of monolithic concrete walls for swimming pools. This method of construction has been commercially very successful for a considerable number of years. The factory formed shuttering elements are heavy to handle and also are difficult to transport as they are comparatively bulky, in view of the spacing between the slabs.

It is an object of the invention to provide a method of constructing a wall for a swimming pool using shuttering components which are lighter and less bulky to transport.

Further objects include the provision of improved shuttering constructions for swimming pool walls, and the improvement of the thermal insulation properties of the walls.

In accordance with a first aspect of the invention, there is provided a method of forming a wall of a swimming pool by casting concrete into shuttering assembled on site from modular components, in which the shuttering is built up on site from elements comprising inner and outer slabs assembled together in a predetermined spaced relationship, and in which at least an external face of the shuttering is formed by the outer slabs which are of a thermally insulating foamed plastics material.

In accordance with a second aspect of the invention, there is provided shuttering assembled on site from modular components for the casting of a swimming pool wall, in which the shuttering is built up on site from separable elements comprising inner and outer slabs assembled together in a predetermined spaced relationship, and in which at least an external face of the shuttering is formed by the outer slabs which are of a thermally insulating foamed plastics material.

Preferably, both the inner and the outer slabs are formed of a thermally insulating foamed plastics material, which may be a high density polystyrene.

The outer slabs are preferably left in situ after pouring of the concrete, so as to provide a layer of thermally insulating material around the pool.

The inner slabs may be removed after pouring and setting of the concrete, and deposited outside the outer slabs prior to back-filling the cavity outside the outer slabs.

The slabs of each element are conveniently held together in spaced relationship by tie bars, which may be of plastics material. The tie bars may each be provided with a frangible zone to enable them to be broken off substantially flush with the exposed concrete face when the inner slabs are removed.

In order to provide reasonably sound joints between the respective slabs of adjacent shuttering elements, the slabs may each have at least one edge, which is normaliy a generally vertical edge, presenting a longitudinal recess, while the opposite edge is provided with a projection co-operating with the said recess on an adjacent similar slab to allow some angular relative movement without detriment to the effect of the seal between the abutting edges.

In accordance with a further aspect of the invention, there is provided a wall of a swimming pool when formed by a method according to the invention as set forth above, or when cast in shuttering according to the invention as set forth above.

The invention will be further described with reference to the accompanying diagrammatic drawings, in which: Figure 1 is a horizontal sectional viewthrough one shuttering element and parts of two adjacent shuttering elements in shuttering in accordance with a preferred form of the invention; Figure 2 is a vertical sectional view showing a modification; and Figure 3 is a perspective view of parts of two adjacent elements and illustrating some further modifications.

In the arrangement shown in Figure 1,atypical shuttering element is shown as comprising a first slab or block 11 and a second slab or block 12 which are interconnected by tie bars 13. Each of the blocks 11 and 12 is of high density expanded polystyrene to give it substantial strength and also thermal insulation properties. The block 11 is shown as being somewhat shorter than the block 12 and the ends 14 of the blocks are shown as being inclined.

The tie bars 13 are of a suitable plastics material and pass through preformed passage in the blocks 11 and 12 so as to extend somewhat beyond the outer surface of each of these blocks. Fitted over each of the ends of each tie bar 13 is a disc 15 which is held in place by means of a holding pin passing through an aperture 16 which is provided in each end of each tie bar 13. The tie bars 13 are a light interference fit in preformed apertures in the blocks 11 and 12 so that the latter remain in position on the tie bars during assembly.

Figure 1 also shows how the tie bars 13 can be used for location of vertical reinforcement bars 17 of high tensile steel, and these vertical bars 17 may themselves be used to support horizontal reinforcing bars 18, also of high tensile steel. These reinforcing bars 17 and 18 are in the cavity 19 defined within the shuttering formed by the assembled elements.

In addition to showing the complete element formed by the blocks 11 and 12 and the associated tie bars, Figure 1 also shows parts of adjacent elements. It will be seen that the block 12 is adjacent a block 1 Ia similar to block 11, but reversed, on either side, and the block 11 is itself adjacent to blocks 12a, again similar to the blocks 12 but reversed. The adjacent faces 14 of the blocks 11 and 12a and 12 and 1 la are shown as being spaced, but in practice they will abut quite closely together when the blocks are in alignment, and thus form an effective seal. If required, a suitable adhesive may be applied between the abutting faces 14 to solidify the shuttering. Similarly, adhesive may be provided between the adjacent horizontal faces of the blocks.

By way of example, the blocks 11 and 12 may each be 1 foot (30 cm) high by approximately 2 feet (60 cm) long by 2.5 inches (6 cm) thick. The spacing between blocks, i.e. the width of the cavity may be 6 inches to 8 inches (15 to 20 cm).

The arrangement described above is for forming straight walls. Where a wall has to have a curve, the arrangement is that the longer blocks 12 are arranged around the outside of the curve while the shorter blocks 11 are in the inside. The radius can be varied from the minimum in which all the inner blocks are short blocks 11 by having some of the blocks on the inner side longer blocks or some of the blocks on the outer side shorter.

Since the elements are built up on site, rather than in the factory, the user has a choice of operation.

It may be found useful when making radiused walls to put offcuts or other filler in between the faces 14 which do not fit as an exact match.

Once the shuttering is assembled and complete, the concrete is poured into the cavity 19 and vibrated and allowed to set.

Once the concrete has been poured and is sufficiently set to be self-supporting, it is envisaged that the blocks on the internal face will be removed so as to present a concrete face for rendering and tiling on the inner surface of the pool. The outer surface formed bythe blocks 11 and 12awill remain in position and since it is formed of thermally insulating material, its presence will reduce the amount of heat lost from the pool into the surrounding ground.

The used blocks from the inner face may be disposed of within the excavation outside the blocks 11 and 1 2a if appropriate. This will tend to assist in thermal insulation, and reduce the amount of soil infilling which is necessary.

It will be appreciated that the pool is normally constructed by excavating rather more than the total pool area and then building the pool wall slightly inside the outer perimeter of the excavation.

Surplus space then has to be back filled using aggregate or hardcore, and the use of the discarded blocks for this purpose is, therefore, advantageous.

When the blocks 1 1a and 12 are removed by releasing the locking pins and withdrawing the discs 15 and then pulling the blocks away from the formed wall, the tie bars are left projecting. In order to enable the tie bars to be readily broken off, they are provided with cutaways to provide zones of weakness in the region of the points 21 so that they may be broken off substantially flush with the wall.

Turning now to Figure 2, there is shown an arrangement by which slabs or blocks 22 and 23 are assembled together using H form clips 24 with integral tie bars 25. The clips 24fit over the upper surfaces of the blocks and receive the lower parts of the superjacent blocks to hold them together.

The clips may again be of plastics material, and those for at least the blocks to be removed may be made frangible, by providing weakened zones in order that the clip will not project from the formed concrete wall.

In certain arrangements, it may be preferred that the inner wall, i.e. the pool-side of the shuttering may remain in position, and if this is done, then a lightweight aggregate can be used for this face rather than the plastics material. In such a case, the exposed face of the shuttering would be rendered after pouring and setting of the concrete.

In such an arrangement, since no provision has to be made for removal of the protruding part of the tie bar, it may be preferred for the tie bars to be set into blind holes such as 25 on the inner face of a light aggregate siab or block, and use may then be made of a disc and securing pin arrangement at the other end of the tie bar to hold the outer surface thermally insulating plastics block.

In view of the lightness and consequent ease of handling of the slabs of foam material and the elements composed of them, the individual slabs may be made in large sizes, e.g. approximately 4 feet (120 cm) high by 2 feet (60 cm) long. An arrangement of two elements of large size slabs 31 and 32 is shown in figure 3. The tie bars are shown at33.

It is also important to note that the vertical edges 34 and 35 respectively of the slabs are convex and concave respectively, when viewed in horizontal section, so as to present projections and matching recesses to improve the seal between adjacent slabs, and also to enable the slabs to take up different relative angular positions without affecting the seal between them in any adverse way. The building up of arcuate or radiussed walls is thus assisted.

In order to provide a foundation, use may be made of the techniques and foundation elements forming the subject matter of our co-pending patent application No. 8432349 filed simultaneously herewith and entitled "Foundation Arrangement".

Various other modifications may be made within the scope of the invention.

Claims (23)

1. A method of forming a wall of a swimming pool by casting concrete into shuttering assembled on site from modular components, in which the modular components of the shuttering are built up on site from elements comprising inner and outer slabs assembled together in a predetermined spaced relationship, and in which at least an external face of the shuttering is formed by the outer slabs which are of a thermally insulating foamed plastics material.

2. A method as claimed in claim 1, in which both the inner and the outer slabs are formed of a thermally insulating foamed plastics material.

3. A method as claimed in claim 1 or 2, in which the foamed plastics material is a high density polystyrene.

4. A method as claimed in any of claims 1 to 3, in which the outer slabs are left in situ after pouring of the concrete.

5. A method as claaimed in any of the preceding claims, in which the inner slabs are removed after pouring and setting of the concrete.

6. A method as claimed in claim 5, in which the removed inner slabs are disposed outside the outer slabs prior to back-filling the cavity outside the outer slabs.

7. A method as claimed in any of the preceding claims, in which the slabs of each element are held together in spaced relationship by tie bars.

8. A method as claimed in claim 7, in which the tie bars are of plastics material.

9. A method as claimed in claim 8 (as dependent on claim 5 or 6), in which the tie bars are each provided with a frangible zone to enable them to be broken off substantially flush with the exposed concrete face when the inner slabs are removed.

10. A method as claimed in any of claims 1 to 6, in which the slabs are held in spaced relationship by H form clips engaging the slabs and interconnected by tie bars.

11.Amethod of forming a wall of a swimming pool substantially as hereinbefore described with reference to the accompanying drawings.

12. A swimming pool wall formed by a method as claimed in any of the preceding claims.

13. Shuttering assembled on site from modular components for the casting of a swimming pool wall, in which the modular components of the shuttering are built up on site from separable elements comprising inner and outer slabs assembled together in a predetermined spaced relationship, and in which at least an external face of the shuttering is formed by the outer slabs which are of a thermally insulating foamed plastics material.

14. Shuttering as claimed in claim 13, in which both the inner and the outer slabs are formed of a thermally insulating foamed plastics material.

15. Shuttering as claimed in claim 13 or 14, in which the foamed plastics material is a high density polystyrene.

16. Shuttering as claimed in any of claims 13 to 15, in which the slabs of each element are held together in spaced relationship by tie bars.

17. Shuttering as claimed in claim 16, in which the tie bars are of plastics material.

18. Shuttering as claimed in claim 17, in which the tie bars are each provided with a frangible zone to enable them to be broken off substantially flush with an exposed concrete face when the inner slabs are removed.

19. Shuttering as claimed in any of claims 13 to 15, in which the slabs are held in spaced relationship by H form clips engaging the slabs and interconnected by tie bars.

20. Shuttering as claimed in any of claims 13 to 19, in which the slabs each have at least one edge presenting a longitudinal recess, while the opposite edge is provided with a projection co-operating with the said recess on an adjacent similar slab to allow some angular relative movement without detriment to the effect of the seal between the abutting edges.

21. Shuttering as claimed in claim 20, in which the said at least one edge is a generally vertical edge.

22. Shuttering for a swimming pool wall, substantially as hereinbefore described with reference to the accompanying drawings.

23. A swimming pool wall when cast in shuttering as claimed in any of claims 13 to 22.