U.S. patent application number 13/640634 was filed with the patent office on 2013-02-28 for protective shelter.
This patent application is currently assigned to Hesco Bastion Limited. The applicant listed for this patent is James Heselden. Invention is credited to James Heselden.
Application Number | 20130047829 13/640634 |
Document ID | / |
Family ID | 42289845 |
Filed Date | 2013-02-28 |
United States Patent
Application |
20130047829 |
Kind Code |
A1 |
Heselden; James |
February 28, 2013 |
PROTECTIVE SHELTER
Abstract
A protective shelter is provided offering opposite outer
supports and a roof structure extending between the supports,
wherein the roof structure comprises a first layer covering a space
between the outer supports and providing a first level of
protection to the shelter and a second layer in the form of a
pre-detonation screen providing a second level of protection to the
shelter, wherein the pre-detonation screen comprises a plurality of
individual panels arranged and supported over and spaced from the
first layer, at least one of the individual panels comprising a
first panel material presenting a substantially closed surface to
an incoming projectile and at least one second panel material
forming an edging strip to the first panel material and being of
greater rigidity than the first panel material.
Inventors: |
Heselden; James; (Leeds,
GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Heselden; James |
Leeds |
|
GB |
|
|
Assignee: |
Hesco Bastion Limited
Leeds, Yorkshire
GB
|
Family ID: |
42289845 |
Appl. No.: |
13/640634 |
Filed: |
April 8, 2011 |
PCT Filed: |
April 8, 2011 |
PCT NO: |
PCT/GB2011/050701 |
371 Date: |
November 5, 2012 |
Current U.S.
Class: |
89/36.02 ;
89/904; 89/920 |
Current CPC
Class: |
E04B 2001/3252 20130101;
E04B 1/3205 20130101; E04H 9/10 20130101; E04B 2001/3294
20130101 |
Class at
Publication: |
89/36.02 ;
89/904; 89/920 |
International
Class: |
F41H 5/24 20060101
F41H005/24; E04H 9/06 20060101 E04H009/06; F41H 5/04 20060101
F41H005/04 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 23, 2010 |
GB |
1006816.1 |
Claims
1. A protective shelter offering opposite outer supports and a roof
structure extending between the supports, wherein the roof
structure comprises a first layer covering a space between the
outer supports and providing a first level of protection to the
shelter and a second layer in the form of a pre-detonation screen
providing a second level of protection to the shelter, wherein the
pre-detonation screen comprises a plurality of individual panels
arranged and supported over and spaced from the first layer, at
least one of the individual panels comprising a first panel
material presenting a substantially closed surface to an incoming
projectile and at least one second panel material forming an edging
strip to the first panel material and being of greater rigidity
than the first panel material.
2. The protective shelter according to claim 1, wherein: a. the
second panel material is of greater shear strength than the first
panel material; and/or b. the second panel material is of greater
tensile strength than the first panel material; and/or c. the
second panel material is less brittle than the first panel
material; and/or the second panel material is of greater smoothness
than the first panel material.
3. The protective shelter according to claim 1, wherein the edging
strip is formed by at least one pre-detonation screen edge element
formed from the second panel material.
4. The protective shelter according to claim 3, wherein the
pre-detonation screen edge element comprises a channel into which
an edge of the panel is received.
5. The protective shelter according to claim 4, wherein the
pre-detonation screen edge element comprises two opposed channels
into which the edges of two neighbouring panels are received.
6. The protective shelter according to claim 1, wherein the first
layer is supported on at least one of the outer supports by an
anchor beam comprising a first longitudinal beam element comprising
a plurality of anchor beam components arranged end to end and a
second neighbouring longitudinal beam element side by side with the
first element and comprising a plurality of anchor beam components
arranged end to end, joints between individual anchor beam
components of the first longitudinal element being staggered with
respect to joints between individual anchor beam elements of the
second longitudinal element.
7. The protective shelter according to claim 1, wherein the
pre-detonation screen is supported above the first layer by a
plurality of rafters extending from the first layer and by a purlin
supporting at least a plurality of the rafters, the purlin
comprising a plurality of individual purlin components overlapping
with and staggered with respect to one or more neighbouring purlin
components and connected together by one of more connecting
elements to form a continuous but staggered purlin.
8. A protective shelter offering opposite outer supports and a roof
structure extending between the supports, wherein the roof
structure comprises a first layer covering a space between the
outer supports and providing a first level of protection to the
shelter, and a second layer in the form of a pre-detonation screen
providing a second level of protection to the shelter, wherein the
pre-detonation screen is supported above the first layer by a
plurality of rafters extending from the first layer and by a purlin
supporting at least a plurality of the rafters, the purlin
comprising a plurality of individual purlin components overlapping
with and staggered with respect to one or more neighbouring purlin
components and connected together by one of more connecting
elements to form a continuous but staggered purlin.
9. The protective shelter according to claim 8, wherein the first
layer is supported on at least one of the outer supports by an
anchor beam comprising a first longitudinal beam element comprising
a plurality of anchor beam components arranged end to end and a
second neighbouring longitudinal beam element side by side with the
first element and comprising a plurality of anchor beam components
arranged end to end, joints between individual anchor beam
components of the first longitudinal element being staggered with
respect to joints between individual anchor beam elements of the
second longitudinal element.
10. The protective shelter according to claim 8, wherein the
connecting elements comprise a plurality of channels for receiving
the purlin components.
11. The protective shelter according to claim 10, wherein the
connecting elements comprise at least one flange for connection to
the rafter beam.
12. The protective shelter according to claim 11, wherein the width
of the flange and the length of the channel are substantially the
same.
13. A protective shelter offering opposite outer supports and a
roof structure extending between the supports, wherein the roof
structure comprises a first layer covering a space between the
outer supports and providing a first level of protection to the
shelter, and a second layer in the form of a pre-detonation screen
providing a second level of protection to the shelter, wherein the
first layer is supported on at least one of the outer supports by
an anchor beam comprising a first longitudinal beam element
comprising a plurality of anchor beam components arranged end to
end and a second neighbouring longitudinal beam element side by
side with the first element and comprising a plurality of anchor
beam components arranged end to end, joints between individual
anchor beam components of the first longitudinal element being
staggered with respect to joints between individual anchor beam
elements of the second longitudinal element.
14. The protective shelter according to claim 13, wherein the first
layer of the roof structure comprises a plurality of tray members
arranged to receive earth, sand or aggregate material defining an
inner skin to provide a first level of protection in the roof
structure, and the tray members are arranged to be supported by
transverse beams, wherein the transverse beams are arranged to be
supported at their respective ends by the opposite outer
supports.
15. The protective shelter according to claim 14, wherein the
transverse beams form a transverse beam bridge across the shelter
such that the height of the shelter centrally, and away from the
opposite supports is substantially the same as the height of said
supports.
16. The protective shelter according to claim 14, wherein the
transverse beams are arranged to define a shallow arch across the
shelter such that the internal height of the shelter centrally, and
away from the opposite supports is greater than the height of said
supports.
17. The protective shelter according to claim 13, wherein the tray
members comprise a series of inter connected identical tray members
having mutually connectable engagement formations at opposite ends
thereof.
18. The protective shelter according to claim 13, wherein the outer
supports are formed from gabions comprising opposed side walls
comprising a plurality of side wall elements connected together at
spaced intervals by a plurality of partition walls such that spaces
between neighbouring pairs of partition walls define, together with
the side walls, individual compartments of the gabion, adjacent
side and partition walls being connected to one another by pivotal
connections enabling the gabion to be folded between fully
flattened and deployed configurations.
19. The protective shelter according to claim 18, wherein at least
one of the pivotal connections is a releasable connection which
when released allows a side wall element to open with respect to
the gabion to allow access from the side of the gabion to any
contents of the gabion compartments.
20. The protective shelter according to claim 18, wherein
stanchions are situated in one or more of the gabion units,
providing additional support between the ground and the roof
structure.
21. The protective shelter according to claim 7, wherein the
connecting elements comprise a plurality of channels for receiving
the purlin components.
22. The protective shelter according to claim 1, wherein the first
layer of the roof structure comprises a plurality of tray members
arranged to receive earth, sand or aggregate material defining an
inner skin to provide a first level of protection in the roof
structure, and the tray members are arranged to be supported by
transverse beams, wherein the transverse beams are arranged to be
supported at their respective ends by the opposite outer
supports.
23. The protective shelter according to claim 8, wherein the first
layer of the roof structure comprises a plurality of tray members
arranged to receive earth, sand or aggregate material defining an
inner skin to provide a first level of protection in the roof
structure, and the tray members are arranged to be supported by
transverse beams, wherein the transverse beams are arranged to be
supported at their respective ends by the opposite outer
supports.
24. The protective shelter according to claim 1, wherein the outer
supports are formed from gabions comprising opposed side walls
comprising a plurality of side wall elements connected together at
spaced intervals by a plurality of partition walls such that spaces
between neighbouring pairs of partition walls define, together with
the side walls, individual compartments of the gabion, adjacent
side and partition walls being connected to one another by pivotal
connections enabling the gabion to be folded between fully
flattened and deployed configurations.
25. The protective shelter according to claim 8, wherein the outer
supports are formed from gabions comprising opposed side walls
comprising a plurality of side wall elements connected together at
spaced intervals by a plurality of partition walls such that spaces
between neighbouring pairs of partition walls define, together with
the side walls, individual compartments of the gabion, adjacent
side and partition walls being connected to one another by pivotal
connections enabling the gabion to be folded between fully
flattened and deployed configurations.
Description
FIELD
[0001] The present invention relates to a protective shelter and,
in particular, to such a shelter that can provide protection within
a war zone and which can be readily assembled in a quick, secure
and reliable manner.
BACKGROUND
[0002] While a variety of requirements arise for temporary, or at
least quickly-built shelters, there is generally a compromise
between the level of protection offered by the shelter and the
speed, reliability and ease with which such a structure can be
built.
[0003] Also, the degree of protection required by the shelter can
change over time and known protective shelters, while perhaps
providing an appropriate initial level of protection, may not be
suited to a scenario in which a lesser, or greater, degree of
protection is required.
[0004] Our co-pending applications PCT/GB2008/050275 and
PCT/GB2009/051431 describe certain types of shelter which utilise a
shallow-arched roof structure to provide support for a ballast
material to protect the shelter from explosive attack.
[0005] However, we have now developed certain improvements to these
structures, particularly although not exclusively with reference to
pre-detonation screens for such structures and to certain
structural improvements allowing for greater strength and greater
ease of manufacture and assembly, and this invention consequently
seeks to provide for a protective shelter having certain advantages
over known such shelters.
BRIEF DESCRIPTION OF THE FIGURES
[0006] The invention is described further hereinafter, by way of
example only, with reference to the accompanying drawings in
which:
[0007] FIG. 1 shows a panel formed from a first panel material, to
be used in the construction of a pre-detonation screen according to
a first aspect of the invention;
[0008] FIG. 2 shows an edge element formed from a second panel
material for providing an edging strip to the panel shown in FIG.
1;
[0009] FIGS. 3, 4 and 5 show photographs of the shelter of the
invention in construction at the stage of assembly of the
pre-detonation screen;
[0010] FIG. 6 shows a connecting element for connecting purlin
components together in the construction of a pre-detonation screen
according to a second aspect of the present invention;
[0011] FIG. 7 shows a rafter component;
[0012] FIG. 8 shows a purlin component;
[0013] FIGS. 9 and 10 show photographs illustrating the insertion
of the connecting element of FIG. 6 into the rafter component of
FIG. 7;
[0014] FIGS. 11 and 12 show anchor beam components use in the
construction of a roof structure according to a third aspect of the
invention; and
[0015] FIGS. 13 and 14 show photographs of a shelter in accordance
with the invention at the stage of construction of the anchor beam
assemblies.
DETAILED DESCRIPTION
[0016] As will be appreciated from the following description,
examples of a shelter embodying the present invention can be
quickly and, importantly, reliably constructed in a manner
requiring a minimum number of personnel and, critically, in a
manner such that each separate component of the structure can be
removed and lifted, preferably single handedly.
[0017] Also, all separate components can advantageously be of a
size such that they are readily transportable, in flat-packed
unassembled form on a pallet, such as a pallet of dimensions 2
metres.times.2.2 metres, preferably on a pallet of dimensions 1.2
metres.times.1.2 metres.
[0018] According to a first aspect of the present invention, there
is provided a protective shelter offering opposite outer supports
and a roof structure extending between the supports, wherein the
roof structure comprises a first layer covering a space between the
outer supports and providing a first level of protection to the
shelter and a second layer in the form of a pre-detonation screen
providing a second level of protection to the shelter, wherein the
pre-detonation screen comprises a plurality of individual panels
arranged and supported over and spaced from the first layer, at
least one of the individual panels comprising a first panel
material presenting a substantially closed surface to an incoming
projectile and at least one second panel material forming an edging
strip to the first panel material and being of greater rigidity
than the first panel material.
[0019] The primary purpose of the pre-detonation screen is to cause
an incoming explosive projectile to detonate on the pre-detonation
screen and not on the first layer of the roof structure. Typically,
in the event of such an attack the pre-detonation screen acts as a
sacrificial layer, protecting the first layer from the primary
detonation of the projectile. Our co-pending applications
PCT/GB2008/050275 and PCT/GB2009/051431 describe briefly the use of
pre-detonation screens, typically of plywood, but we have now found
that an improved form of pre-detonation screen may be obtained by
the use of composite panel elements making up the screen, wherein
those elements or any of them comprise a first panel material
presenting a substantially closed surface to the incoming
projectile and at least one second panel material forming an edging
strip to the first panel material and being of greater rigidity
than the first panel material. Exemplary materials for the first
and second panel materials include woods, plastics, metals and
composites. However, the second panel material should be selected
to have greater rigidity than the first. In this way, the risk of
gaps appearing in the pre-detonation screen as it is subjected to
warping and flexing, particularly when deployed in harsh climatic
conditions, is minimised. One preferred material for the first
panel material is wood, especially plywood, and one preferred
material for the second panel material is metal, especially
aluminium, and from now on in this specification we shall make
reference only to those especially preferred materials. It will
however be easily understood that the selection of appropriate
alternative materials is well within the capability of the skilled
addressee.
[0020] Preferably the second panel material is of greater shear
strength than the first panel material.
[0021] Preferably the second panel material is of greater tensile
strength than the first panel material.
[0022] Preferably the second panel material is less brittle than
the first panel material.
[0023] Preferably the second panel material is of greater
smoothness than the first panel material, allowing an improved and
seamless fit between neighbouring panels of the screen.
[0024] Also preferably, the first panel material forms a panel and
the second panel material forms an edging strip to the panel. The
edging strip may be formed on one or more edges of the panel,
preferably on at least two edges of the panel. The edging strip may
be continuous or discontinuous. Its primary function is to
reinforce the edges of the panel to prevent warping and bending of
the panel in deployment and the consequent appearance of gaps in
the pre-detonation screen through which an incoming projectile may
pass.
[0025] The edging strip is preferably formed by at least one
pre-detonation screen edge element formed from the second panel
material. Preferably the pre-detonation screen edge element
comprises a channel into which an edge of the panel may be
received. Even more preferably, the pre-detonation screen edge
element comprises two opposed channels into which the edges of two
neighbouring panels may be received. The channels may oppose each
other directly in a flat pre-detonation screen section or may be
offset to allow and arched pre-detonation screen section to be
constructed.
[0026] According to a second aspect of the present invention, there
is provided a protective shelter offering opposite outer supports
and a roof structure extending between the supports, wherein the
roof structure comprises a first layer covering a space between the
outer supports and providing a first level of protection to the
shelter, and a second layer in the form of a pre-detonation screen
providing a second level of protection to the shelter, wherein the
pre-detonation screen is supported above the first layer by a
plurality of rafters extending from the first layer and by a purlin
supporting at least a plurality of the rafters, the purlin
comprising a plurality of individual purlin components overlapping
with and staggered with respect to one or more neighbouring purlin
components and connected together by one of more connecting
elements to form a continuous but staggered purlin.
[0027] The provision of a purlin supporting a plurality of the
rafters provides important advantages in terms of the structural
stability of the roof structure generally and the pre-detonation
screen in particular. It also enables the entire roof structure to
be pre-assembled before being lifted by crane onto the opposite
outer supports. This enables construction of the roof structure at
a remote location, perhaps away from incoming fire or from other
hostile activity, or simply away from a place of exposure.
[0028] The connecting elements preferably have a plurality (usually
two) of channels for receiving the purlin components. Generally,
those channels will be adjacent one another. The connecting element
is also preferably provided with a flange element for insertion
into, or connection to, the rafter beam to secure the connecting
element in place. Typically the rafter beam comprises a plurality
of rafter beam components which are arranged end to end to form the
rafter beam, with connecting elements inserted at the interstices
between rafter beam components. When the connected element is
mounted between two rafter beam components in this way, it
preferably comprises a pair of opposed flanges for respective
insertion into, or connection to, neighbouring rafter beam
components. Staggering the components of the purlin with respect to
each other has the important benefit in this case that it enables
the connector elements to be made by extrusion since the width of
the flange element for insertion into the rafter is substantially
the same as the length of the each channel receiving the purlin
components.
[0029] Thus, preferably the connecting elements comprise a
plurality of channels for receiving the purlin components. Also
preferably, the connecting elements comprise at least one flange
for insertion into the rafter beam. Preferably the width of the
flange and the length of the channel are substantially the same,
enabling the connecting element to be manufactured by extrusion,
particularly if the element is of metal or plastic construction.
Aluminium is the preferred material.
[0030] According to a third aspect of the present invention, there
is provided a protective shelter offering opposite outer supports
and a roof structure extending between the supports, wherein the
roof structure comprises a first layer covering a space between the
outer supports and providing a first level of protection to the
shelter, and a second layer in the foiin of a pre-detonation screen
providing a second level of protection to the shelter, wherein the
first layer is supported on at least one of the outer supports by
an anchor beam comprising a first longitudinal beam element
comprising a plurality of anchor beam components arranged end to
end and a second neighbouring longitudinal beam element side by
side with the first element and comprising a plurality of anchor
beam components arranged end to end, joints between individual
anchor beam components of the first longitudinal element being
staggered with respect to joints between individual anchor beam
elements of the second longitudinal element.
[0031] The provision of a plural longitudinal beam elements has
been found to offer significantly greater structural stability to
the roof structure generally and the pre-detonation screen in
particular. Preferably the first longitudinal beam element is
formed from a plurality of first (outer) anchor beam components,
each component laying substantially flat on the outer supports but
offering an inclined channel for receiving panel elements of a
pre-detonation screen. Preferably the second longitudinal beam
element is formed from a plurality of second (inner) anchor beam
components, each component laying substantially flat on the outer
supports and adjacent the components of the first beam element, but
with the joints therebetween staggered with respect to each other.
First and second longitudinal beam elements may be secured together
by transverse beams forming the first layer of the roof
structure.
[0032] Preferably the first layer of the roof structure comprises a
plurality of tray members arranged to receive earth, sand or
aggregate material defining an inner skin to provide a first level
of protection in the roof structure, and the tray members are
arranged to be supported by transverse beams, wherein the
transverse beams are arranged to be supported at their respective
ends by the opposite outer supports. The transverse beams may form
a transverse beam bridge across the shelter such that the height of
the shelter centrally, and away from the opposite supports is
substantially the same as the height of said supports.
Alternatively, the beams may be arranged to define a shallow arch
across the shelter such that the internal height of the shelter
centrally, and away from the opposite supports is greater than the
height of said supports.
[0033] In order to assist the quick and reliable formation of such
a bridge structure, the supporting transverse beams members
advantageously comprise transverse beams of identical shape and
configuration. Each transverse beam member may comprise a plurality
of transverse beams joined together end-to-end by any suitable
connecting means, such as one or more flitch plates for example. In
the case of an arched bridge structure, the ends of each transverse
beam member may be chamfered so as to connect end to end to form an
arched section.
[0034] A greater plurality of beam members--for example three, four
or five--may be provided end-on end, with suitable connecting
members; although in this case it may be necessary for the shelter
to be provided with one or more internal stanchions for supporting
the roof beam assembly.
[0035] In a preferred embodiment, each transverse beam is provided
by two transverse beam members joined end to end. Preferably, each
transverse beam member is identical. Preferably, a vertical member
of the transverse beams includes sections to accommodate flitch
plates, for supportively connecting the transverse beams.
Preferably still, the sections are controlled tolerance channels in
the transverse beams. Advantageously, securing the transverse beams
with the flitch plates in this manner creates a strong continuous
transverse roof beam.
[0036] Preferably, each roof beam member is joined end-to-end with
its paired roof beam member in a manner which provides a continuous
straight-line or arched join.
[0037] The ends of the transverse beams are arranged to be
supported by the outer supports, and may be advantageously be
arranged to be connected to anchor beam components on the outer
supports.
[0038] The anchor beam components advantageously serve to space the
transverse beams along the length of the shelter and are arranged
such that each transverse beam is effectively connected to, in a
secure manner, adjacent anchor beam components. Advantageously, a
the anchor beam components are arranged along the opposite outer
supports to form an anchor beam comprising a first longitudinal
beam element comprising a plurality of anchor beam components laid
end to end, and a second neighbouring longitudinal beam element
side by side with the first element and comprising a plurality of
anchor beam components arranged end to end, the joints between
individual anchor beam components of the first longitudinal element
being staggered with respect to joints between individual anchor
beam elements of the second longitudinal element. Preferably the
transverse beams are connected to anchor beam components in both
the first and the second longitudinal beam elements.
[0039] In any case, the anchor beam components, through their
secure engagement to the transverse roof beams, provide for a rigid
footing/support structure that extends along the length of the
upper surface of the walls of the shelter and thereby combine to
effectively define a lintel transverse beam extending along the
length of the wall. Such rigid supporting structure provided by the
anchor beam serves to define the aforementioned lintel transverse
beam in a manner such that, should the outer wall suffer damage, or
the integrity thereof be in any way compromised, the rigidity and
stability of the overall roof structure can remain intact
advantageously serving to retain the roof structure in place in
spite of any such damage to the wall(s).
[0040] The structure of the invention can advantageously include a
second laterally extending layer, spaced from the tray members and
arranged so as to define a pre-detonation screen. The
pre-detonation screen preferably comprises a plurality of
individual panels arranged and supported over and spaced from the
first layer, at least one of the individual panels comprising a
first panel material presenting a substantially closed surface to
an incoming projectile and at least one second panel material
forming an edging strip to the first panel material and being of
greater rigidity than the first panel material.
[0041] The pre-detonation screen is advantageously spaced from the
initial layer formed by the tray members and the soil, sand,
aggregate layer by a distance in the order of from about 0.5 metres
to about 2 metres, for example.
[0042] Preferably, the tray members comprise a series of inter
connected identical tray members having mutually connectable
engagement formations at opposite ends thereof.
[0043] Preferably each tray member comprises a plurality of tray
sections. Each tray section may be separated from its neighbouring
tray section by a stiffening flange to give extra structural
robustness to the tray member.
[0044] As a further feature, the portions of the roof structure
provided above the earth, sand or aggregate layer can
advantageously be formed from the inter connected metal poles, for
example such as scaffold poles.
[0045] Such poles are arranged to provide roof trusses and rafter
poles, within the overall structure of the roof. As one example,
the pre-detonation screen can comprise plywood panels having a
thickness of 19 mm.
[0046] As should be appreciated from the above, and from the
description below, the invention is particularly advantageous
insofar as the roof structure can be readily formed on gabion units
which are arranged to form the opposite walls of the shelter.
[0047] The wall structures can be formed from structural blocks
such as those that are the subject matter of European patent
0466726, European patent 1951963 or European patent application
06779610.2. Continuous wall structures, and other types of modular
wall structure (concrete blocks for example) are also contemplated.
Particularly preferred wall structures are of the type described in
European patent 1951963, namely that at least one wall structure is
formed from a gabion comprising opposed side walls comprising a
plurality of side wall elements connected together at spaced
intervals by a plurality of partition walls such that spaces
between neighbouring pairs of partition walls define, together with
the side walls, individual compartments of the gabion, adjacent
side and partition walls being connected to one another by pivotal
connections enabling the gabion to be folded between fully
flattened and deployed configurations, wherein at least one of the
pivotal connections is a releasable connection which when released
allows a side wall element to open with respect to the gabion to
allow access from the side of the gabion to any contents of the
gabion compartments. Such gabions are openable to facilitate
dismantling or repair.
[0048] In a particularly preferred arrangement for providing
additional strength to the shelter, when the outer supports
comprise gabion units, stanchions may be situated in one or more of
the gabion units, providing additional support between the ground
and the roof structure.
[0049] The overall protective shelter can then be quickly and
reliably constructed as required, and in a manner responsive to the
level of danger faced, and the level of protection required.
[0050] For example, once the gabions are in place to form the walls
of the shelter, the roof structure can be readily, reliably formed,
requiring a minimal number of personnel and, through use of the
component parts described herein, in a structurally rigid and
reliable manner so as to first provide a basic level of blast
protection by way of the transverse beams and an interlaid series
of connected trays, as described further herein, and the layer of
earth, sand or other aggregate provided thereon.
[0051] Referring to FIGS. 1 to 5, there is shown a protective
shelter 1 in accordance with the invention comprising opposite
outer supports, of which adjacent outer supports 2 and 3 are
visible in FIG. 3. Roof structure 4 extends between the supports to
provide a first layer covering the space between the outer
supports. In the case of the illustrated embodiment the roof
structure first layer is formed from a plurality of trays 5
supported on transverse beams 6 extending across the width of the
shelter in a manner very much as described in our previous
application PCT/GB2009/051431. In use of the shelter the trays will
be filled with an aggregate material providing blast protection,
but no such material is shown in the Figures.
[0052] The roof structure first layer provides a first level of
protection to shelter, but a second level is provided by
pre-detonation screen 7 which comprises a plurality of individual
panels 8 arranged and supported over and spaced from the first
layer and presenting a substantially closed surface to an incoming
projectile. In the illustrated embodiment, panels 8 are made from
plywood, which constitutes the first panel material. The panels are
provided with edging elements 9, formed in this case from extruded
aluminium and comprising opposed channels 10 and 11 into which the
edges of neighbouring panels 9 are received as illustrated in FIGS.
3, 4 and 5.
[0053] Also shown in FIGS. 3, 4 and 5, but now also with reference
to FIGS. 6 to 10 pre-detonation screen 7 is supported above the
first layer of the roof structure by a plurality of rafters 12
extending from the first layer and by purlins 13, each purlin 13
comprising a plurality of individual purlin components 14
overlapping with and staggered with respect to each neighbouring
purlin component, as is best shown in FIGS. 4 and 5, and connected
together by connecting elements 15 to form a continuous but
staggered purlins 13 supporting the pre-detonation screen.
[0054] As will be appreciated with reference to FIGS. 3 to 10 the
connecting elements of this embodiment are arranged to be received
within rafters 12 as illustrated, but many other suitable forms of
connecting element may be envisaged.
[0055] Purlin components 14 are arranged with slots 16 to provide
an interference fit with receiving channels 17 on the connecting
elements but, again many other means may be envisaged to secure the
purlin components into the connecting elements.
[0056] Referring now to FIGS. 3, 4 and 11 to 14, pre-detonation
screen 7 is supported on the opposite outer supports with the aid
of anchor beam 18, which is shown in construction in FIGS. 13 and
14. Anchor beam 18 comprises a first longitudinal beam element
comprising a plurality of first (outer) anchor beam components 19
laid end to end and a second neighbouring longitudinal beam element
side by side with the first element and comprising a plurality of
second (inner) anchor beam components 20 arranged end to end,
joints between individual anchor beam components of the first
longitudinal element being staggered with respect to joints between
individual anchor beam elements of the second longitudinal
element.
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