GB2113269A

GB2113269A - Nuclear shelter

Info

Publication number: GB2113269A
Application number: GB08200855A
Authority: GB
Inventors: Christopher Daniel Dowl Hickey
Original assignee: Lawborough Consultants Ltd
Current assignee: Lawborough Consultants Ltd
Priority date: 1982-01-12
Filing date: 1982-01-12
Publication date: 1983-08-03
Also published as: EP0084428A1; GB2113269B

Description

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GB 2 113 269 A 1

SPECIFICATION Shelters

This invention relates to shelters for use particularly against the effects of nuclear S weapons.

It is well-known that, in the event of an attack using nuclear weapons, large numbers of people not immediately in the neighbourhood of a nuclear explosion could be protected, by means of a 10 suitable shelter, from injury by flash, gamma rays, fall-out radiation and blast. Such shelters may also give protection against chemical and biological attacks.

The present invention is directed to the 15 provision of a form of shelter which can readily be erected to form an airtight structure and which, particularly when covered with a layer of earth, sand, gravel or the like, is capable of giving a large measure of protection in regions where radiation 20 effects are the primary threat to survival.

According to this invention, a shelter comprises a load-bearing skeleton structure surrounded by an impermeable membrane with a layer of resilient material between the membrane and the 25 skeleton structure, a closable access opening through the membrane and resilient material and air supply means for supplying air for breathing to the interior of the structure.

The skeleton structure conveniently is a metal 30 framework, for example formed of steel tubes. The framework is preferably shaped to define a structure having generally curved surfaces at least around the upper and side parts of the structure. It is generally convenient however for the structure 35 to have a substantially flat base.

A generally rounded external shape for the shelter is desirable for withstanding blast.

A metal mesh or other support for the resilient material is preferably provided between the 40 skeleton structure and the resilient material.

The impermeable membrane may be formed of a butyl rubber or other flexible polymeric material. It may be fabricated as a bag having an access opening, in which case the framework is taken in 45 through the access opening and erected inside the bag. Alternatively the impermeable membrane may be formed in more than one unit, e.g. a base sheet and an upper sheet, which sheets are sealed together with airtight seals. Such seals may be 50 formed for example by using an inflatable tube or by using an airtight zip fastener. The access opening may likewise be sealed with an airtight zip fastener or with an inflatable seal. In yet another arrangement, the parts of the 55 impermeable membrane and/or the access opening are sealed by provision of moulded edges which are mechanically clamped together.

Provision of fresh air inside the shelter may be affected in the known way. For example pump 60 means may be provided for drawing air from outside the shelter through a filter; such pump means may have a manually operable mechanical drive and/or an electrical drive powered from a battery or batteries.

The type of shelter described above might typically be erected on a rigid base, for example the floor of a garage but the completely surrounding impermeable membrane extending underneath the framework as well as around the upper parts will serve to keep the interior of the shelter dry even if the shelter is exposed to weather or erected on damp ground.

Preferably the structure has a covering of earth or sand or gravel or other particulate material. It will be readily appreciated that the amount of protection against radiation will depend on the thickness of the covering. Even six inches of earth will give a substantial measure of protection. Preferably however a much thicker layer of earth or gravel or sand, for example three to five feet thick would be provided. The user, after erecting the shelter, would put on as much cover as possible in the circumstances.

Preferably the structural members are arranged to permit of limited deformation of the structure under loads, for example either by resilience of individual structural members or by the provision of separate springs or other resilient elements, preferably with means for limiting deflection of the structure.

The following is a description of one embodiment of the invention, reference being made to the accompanying drawings in which:—

Figure 1 is a diagrammatic section through a shelter; and

Figures 2,3 and 4 are diagrams illustrating components of the structure.

Referring to Figure 1, the shelter is erected on firm ground, for example a concrete base 10 with a layer 11 of sand or gravel to form a bed. The shelter comprises essentially an outer impermeable barrier 12 and an inner skeleton structure 13 with foam padding 14 between the skeleton structure and the outer barrier 12. As seen in Figure 1, the skeleton structure 13 defines a generally curved assembly having a flat base but with no sharp angles apart from where the sides meet the base. In plan the structure is conveniently elongate with curved ends, e.g. of a generally elliptical form. Apart from the outer structural members defining the shape of the skeleton structure, there are a plurality of load-bearing uprights such as the members 15 together with bracing and strengthening struts such as for example are shown at 16 and 17. The horizontal struts 17 towards the side of the structure are conveniently arranged as supports for bunks.

Over the skeleton structure is a layer of metal mesh 18 to form a support for the foam padding 14. The purpose of this padding, which is of nonflammable material, is to provide a support for the outer membrane barrier 12. This is of flexible or semi-flexible material chosen to be resistant to light, ozone, ultraviolet radiation and soil acids. A number of materials are available which might typically have a life of at least 15 years without significant corrosion or deterioration.

The membrane 12 may be formed as a complete bag having an access opening closable

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by a flap or a separate member, conveniently of the same material as the membrane 12, the flap or other closure being sealable to the main membrane structure to form an airtight assembly.

5 The seal may be effected by an airtight zip or by an inflatable tube to form a pressure seal or by a mechanical clamping arrangement.

It may be more convenient however to form the membrane 12 of two or more sheets of 10 impermeable material which are sealed together after the sheets have been positioned under and over the skeleton structure 13 with its foam padding 14.

Provision is made for circulating filtered air 15 through the structure. This is preferably done by a manually operable pump, the operation of which provides exercise for users of the shelter and economises on energy supplies. A battery-powered pump however is preferably also 20 provided.

The unit thus far described, if erected inside a house or garage, would, on its own provide protection against residual radiation and also against attack by gas or biological weapons. 25 Preferably however the whole structure is covered in earth, sand or aggregate as shown at 22. Even six inches of sand or earth will give a significant amount of protection but preferably this outer covering is of the order of three to five feet thick. 30 In the embodiment illustrated in Figure 1 there is a smooth outer skin 23 of metal foil with a thin layer of concrete to give further protection against radiation and to hold the sand or aggregate in place.

35 The blast pressure waves from a nuclear explosion can cause fracturing of a rigid structure and it is preferable to make the structural assembly such that it has a significant amount of "give". Subsidence of the soil may also cause 40 fracturing of a rigid assembly by excessive local loads, particularly with heavy coverings of earth or sand. For these reasons, the structural members are arranged to permit of deformation of the structure. This may be done in various ways. 45 Referring to Figure 2 there is shown one example of a curved load-bearing upright member 30 to give support in a vertical direction on a horizontal upper member 31, the lower end of the member 30 resting on a horizontal member 32. Excessive 50 vertical load will cause deflection of the member 30, this deflection being limited, in this construction, by a secondary upright 33 which will come into contact with the members 31,32 when the deflection of member 30 reaches a 55 magnitude determined by the gaps 34 between the ends of the member 33 of the horizontals 31, 32. In this embodiment, the member 33 is carried on supports 35 from the member 30.

Figures 3 and 4 illustrate constructions in 60 which a certain amount of "give" is permitted by the use of springs. Figure 3 shows two telescopically arranged tubes 40,41 with a compression spring 42 limiting the travel of the tube 40 inside the tube 41. Figure 4 shows a

65 construction in which two load-bearing tubes 50, 51 are axially aligned and are telescopically arranged over an inner guide tube 52. A compression spring 53 between the ends of the tubes 50, 51 limits their relative movement.

70 Structural components such as have been shown in Figures 2, 3 and 4 may be used for the main load-bearing elements in the skeleton structure 13 of Figure 1.

Claims

75 1. A shelter comprising a load-bearing skeleton structure surrounded by an impermeable membrane with a layer of resilient material between the membrane and the skeleton structure, a closable access opening through the

80 membrane and resilient material and air supply means for supplying air for breathing to the interior of the structure.
2. A shelter as claimed in claim 1 wherein the skeleton structure is a metal framework.

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3. A shelter as claimed in claim 2 wherein the framework is formed of steel tubes.
4. A shelter as claimed in either claim 2 or claim 3 wherein the framework is shaped to define a structure having generally curved surfaces at

90 least around the upper and side parts of the structure.
5. A shelter as claimed in claim 4 wherein the framework for the structure has a substantially flat base.

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6. A shelter as claimed in any of the preceding claims wherein a metal mesh or other support for the resilient material is provided between the skeleton structure and the resilient material.
7. A shelter as claimed in any one of the

100 preceding claims wherein the impermeable membrane is formed of a butyl rubber or other flexible polymeric material.
8. A shelter as claimed in any of the preceding claims wherein the impermeable membrane is

105 fabricated as a bag having an access opening.
9. A shelter as claimed in any of claims 1 to 7 wherein the impermeable membrane is formed of two or more sheets sealed together with airtight seals.

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10. A shelter as claimed in any of the preceding claims and having a covering of earth or sand or gravel or other particulate material.
11. A shelter as claimed in any of the preceding claims wherein said structure is arranged to

115 permit of limited deformation of the structure under loads.
12. A shelter as claimed in claim 11 wherein the structure comprises resilient structural members with means for limiting deflection of

120 said members.
13. A shelter as claimed in claim 11 wherein

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the structure comprises spring-restrained
14. A shelter substantially as hereinbefore telescopic members with means for limiting the 5 described with reference to the accompanying telescopic deflection of said members. drawings.

Printed for Her Majesty's Stationery Office by the Courier Press, Leamington Spa, 1983. Published by the Patent Office, 25 Southampton Buildings, London, WC2A 1AY, from which copies may be obtained.