GB2189822A

GB2189822A - Swimming pool construction

Info

Publication number: GB2189822A
Application number: GB08610620A
Authority: GB
Inventors: Richard Michael Burnell; Donald Bridge
Original assignee: Penguin Swimming Pools Ltd
Current assignee: Penguin Swimming Pools Ltd
Priority date: 1986-04-30
Filing date: 1986-04-30
Publication date: 1987-11-04
Also published as: GB8610620D0

Abstract

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 retained by tie bars 11 extending beyond the slabs and having enlarged abutment areas 21 beyond the slabs. An external face of the shuttering is formed by outer slabs which are of a thermally insulating foamed plastics material, the outer slabs being left in situ after pouring of the concrete, so as to provide a layer of thermally insulating material around the pool. The abutment areas on the outer slabs are attached thereto and the tie bars 11 are insertable into these outer abutment areas after passing through the inner slabs and lockable to the outer abutment areas, eg by being threadedly attached thereto by thread 22. The tie bars 11 have frangible zones for removal of the inner ends of the tie bars when the inner slabs are removed. <IMAGE>

Description

SPECIFICATION Swimming pool construction This invention relates to the construction of swimming pools, which term may be taken to include spa pools and paddling pools of excavated type.

The now expired patent specifications GB-A 1038841, GB-A-1103981 and GB-A-1103511 describe the use of shuttering elements comprising two slabs of concrete 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.

In order to provide a method of constructing a wall for a swimming pool using shuttering components which are lighter and less bulky to transport, our co-pending application 8432351, published under number 2162560 describes and claims 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 an external face of the shuttering being formed by outer slabs which are of a thermally insulating foamed plastics material, the outer slabs being left in situ after pouring of the concrete, so as to provide a layer of thermally insulating material around the pool, while the inner slabs are removed after pouring and setting of the concrete.

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

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 enabie them to be broken off substantially flush with the exposed concrete face when the inner slabs are removed.

A problem arising with shuttering for excavated constructions, such as swimming pools, which does not arise with above ground shuttering, is that of access to the external face for insertion or securing, and possible removal, of tie bars holding the inner and outer slabs together.

In accordance with a third 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 retained by tie bars extending beyond the slabs and having enlarged abutment areas beyond the slabs, and an external face of the shuttering being formed by outer slabs which are of a thermally insulating foamed plastics material, the outer slabs being left in situ after pouring of the concrete, so as to provide a layer of thermally insulating material around the pool, the abutment areas on the outer slabs being attached thereto and the tie bars being insertable into these abutment areas after passing through the inner slabs and lockable to the outer abutment areas, for example by a twisting action.

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.

The invention will be further described with reference to the accompanying diagrammatic drawings, in which: Figure 1 is a partial sectional view showing shuttering of the general type to which the present invention relates; Figure 2 is an elevation of a preferred type of tie bar in accordance with the invention; and Figure 3 is an end elevation of an abutment surface.

Fig. 1 shows part of a composite shuttering element comprising outer and inner spaced slabs 1 and 2 respectively, interconnected by tie-bars 11. Each slab 1 or 2 is of high density expanded polystyrene for strength and thermal insulation. Fitted over the end of each tie-bar 11 is a disc 12 shown as being secured by a holding pin 13. Vertical starter reinforcement bars 14 are supported by the tie bars 12 and horizontal starter reinforcement bars 15 are supported by the bars 14. The tie-bars 11 are shown as having points of weakness 16, so that they may be broken off when the inner slabs 2 are removed after pouring.

This type of shuttering is more fully described in our GB-A-2162560.

Fig. 2 shows a tie bar 11 of plastics material having a square end member or disc 21 solid therewith, e.g. by being integrally moulded. The frangible point of weakness 16 is also illustrated as being near the end having the fixed or solid disc 21. The opposite end of the tie bar 11 is provided with a thread 22 and a reduced diameter lead-in portion 23.

Fig. 3 shows an abutment surface 24, also of plastics material and in the form of a square with a central threaded aperture 25 to receive and mate with the thread 22 on the tie bar. In use, the abutment surface 24 is fixed onto the outer slab 1 by adhesive or by being inset into a pre-moulded square indenta tion. The tie bar 11 is inserted and guided by its lead-in portion 23 and then rotated or twisted to engage on the thread in the hole 25. If for any reason, it is desired to remove a tie bar, or replace one in the assembled shuttering, then the tie bar 11 may be removed by twisitng in the reverse direction to release it and then it may be withdrawn, and a new one inserted without the need for access to the outer surfsce of the shuttering which may be hard against the inner surface of an excavation.

Various modifications may be made within the scope of the invention. For instance, a snap fitting or a bayonet type of connection may be provided between the end of the tie bar 11 and the abutment surface 24.

Claims

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 shuttering is built up on site from elements comprising inner and outer slabs assembled together in a predetermined spaced relationship and retained by tie bars extending beyond the slabs and having enlarged abutment areas beyond the slabs, and an external face of the shuttering being formed by outer slabs which are of a thermally insulating foamed plastics material, the outer slabs being left in situ after pouring of the concrete, so as to provide a layer of thermally insulating material around the pool, the abutment areas on the outer slabs being attached thereto and the tie bars being insertable into these abutment areas after passing through the inner slabs and lockable to the outer abutment areas.

2. A method as claimed in claim 1, in which the tie bars are lockable to the outer abutment areas by a twisting action.

3. A method as claimed in claim 2, in which the tie bars are threadedly received in the outer abutment areas.

4. A method as claimed in any of the preceding claims, in which the tie bars are formed with frangible zones for removal of the inner ends of the tie bars when the inner slabs are removed.

5. A method of forming a wall of a swimming pool substantially as hereinbefore described with reference to the accompanying drawings.

6. A wall of a swimming pool when formed by a method as claimed in any of claims 1 to 5.