GB2495902A - Security panel for use in construction of secure structures within buildings - Google Patents

Abstract

The panel comprises two structural layers 112, 114 forming an inner and outer wall of the panel and a core inner barrier layer 106 located in between the structural layers, the barrier layer having a higher level of resistance to penetration than the structural layers. Preferably the barrier layer is ribbed / perforated or may comprise a flattened expanded steel lattice sheet. There may be a second barrier layer located within the panel made from plywood. The panel may connect to adjacent panels via a tongue and groove edge profile where the upper end of the first structural layer comprises two grooves and the lower end comprises a pair of tongues. The panel may also incorporate an integrated lifting strap. Also claimed are a method of constructing the panel, where the structural layers are bonded together using an adhesive. Also claimed is a secure structure comprising a number of panels adjacent to each other to form walls and ceilings.

Description

Security Panel The present invention relates to a security panel for use in the construction of secure structures, including those constructed within existing buildings.

Methods of providing a security panel and constructing a secure structure within a building are also provided.

Buildings often require secure areas within their primary structure in order to protect valuable goods, equipment, documents etc. from unauthorised access. Such secure areas can be constructed from several layers of brick and heavy doors etc. which are arranged to form "secure rooms" within the building. Such secure rooms must be sufficiently strong and secure to prevent attack by an intruder from the outside for a sufficiently long time to enable security personnel to intervene or alternatively cause the intruder to simply give up and flee. Security standards are often set categorised by, amongst other factors, the length of time the structure can withstand a simulated attack by an intruder before breach.

One problem with such semi-permanent secure structures of this type is that it they are expensive and time consuming to build. It is often desirable to construct, relocate or reconfigure secure structures within the building at short notice; however this is often not possible with such semi-permanent secure structures.

According to the present invention there is provided a security panel comprising a plurality of integrated panel layers, the panel layers comprising:-a first structural layer adapted to provide a section of an outer wall of a secure structure; a second structural layer adapted to provide a section of an inner wall of a secure structure; and a first barrier layer provided between the first and second structural layers, the first barrier layer having a higher level of resistance to penetration than the first and second structural layers.

A second barrier layer may be provided. It may be provided between the first barrier layer and the first or second structural layers.

The first and/or second barrier layers may be ribbed and / or perforated to provide a roughened surface.

The first and second structural layers may be provided with engagement means at either end to allow a first security panel to be engaged with a second security panel such that the resulting first and second engaged security panels form a portion of a secure wall. The engagement means may comprise tongue and groove profiles provided at either or both ends of the security panel. The tongue and groove profiles may comprise a pair of grooves provided at the top of the first structural member and a pair of tongues provided at the bottom of the first structural member, a pair of tongues provided at the top of the second structural member and a pair of grooves provided at the bottom of the second structural member. The external dimensions of the tongue profiles are preferably similar to the internal dimensions of the groove profiles in order to provide a tight seal between the first and second security panel of the secure wall.

At least one of the first or second structural layers may be provided with an elongate member at its lower end and a corresponding recess at its upper end in order to provide a concealed channel therebetween when the first and second security panels are engaged to form the secure wall.

The first and second structural layers may comprise a relatively thick layer of mineral fibre material. Optionally, the relatively thick layer of mineral fibre may have a thickness of between around 60mm and 200mm.

The first and second structural layers may comprise a relatively thin skin layer. The skin layer may comprise a layer of coated steel. Portions of the skin layer may extend around the surfaces of the tongue and groove profiles to facilitate engagement with each other when a first security panel is engaged with a second security panel.

The first barrier layer may comprise a lattice structure. The lattice structure may be provided by a flattened, expanded steel sheet.

Optionally, the first barrier layer may have a thickness of between around 2tobmm.

The second barrier layer may comprise a laminar structure. It may be a plywood material. It may have a greater thickness than the first barrier layer, and that thickness may be around 18mm.

Adhesive may be provided between the first and second structural layers in order to secure the first and second structural layers together and to enclose the barrier layer(s) therebetween.

Lifting members may be also be clamped between the first and second structural layers to assist handling of the resulting security panel. The lifting members may comprise lifting straps.

According to the present invention there is also provided a secure structure comprising:-a plurality of said security panels arranged to provide a secure structure, the plurality of security panels being arranged adjacent and on top of one another to form walls and or ceilings of the secure structure.

At least a portion of the plurality of security panels may be secured to one another by a fixing plate extending between each security panel. The fixing plate may be adapted to be inserted in a slot provided between the first and second structural members of first and second adjacent security panels.

Fastening means may be provided to pass through portions of the fixing plate in order to secure adjacent panels. The fastening means may comprise a plurality of fastening screws.

The secure structure may also be provided with an internal divider beam which engages with innermost structural layers of the security panels to retain adjacent columns of security panels in spaced relationship with one another. The internal divider beam may have a u-shaped ridge which is received within a gap between the columns of adjacent security panels.

An external divider member may also be provided which engages with outermost structural layers of the security panels. The external divider member may comprise a u-shaped longitudinal channel having outer flanges which mate with a portion of the outermost skin of the structural member. Packing material may also be provided in the u-shaped channel of the external divider member.

A protective cap may also be provided to cover the external divider member and thereby conceal the joint between columns of adjacent security panels. The protective cap may comprise a u-shaped longitudinal channel adapted to be received within the u-shaped channel of the external divider member. The protective cap may also comprise outer flanges adapted to extend past outer flanges of the external divider member, and may be inwardly bent in order to provide gasket edges which mate with the external skin of the outermost structural layer to prevent access to the join between adjacent columns of security panels. The gasket edges may be provided with resilient sealing means in order to maintain tension against the skin of the outermost structural layer. The resilient sealing means may comprise a strip of rubber or similar material.

Fastening means is provided to secure the security panels to the internal divider beam. The fastening means may comprise a plurality of screws extending through the protective cap, packing material, external divider member, fixing plate and into the internal divider beam.

A cover member is also provided to cover the head of the screws in order to prevent access thereto. The cover member may comprise a strip of resilient material which is received and retained within the u-shaped channel of the protective cap. The strip may comprise flanged ends which correspond with a pair of recesses provided along either edge of the u-shaped channel to provide a snap-fit between the cover member and the protective cap.

According to the present invention there is also provided a method of constructing an integrated securfty panel for use ri constructing a secure structure, the method comprising the steps of:-providing a first structural layer adapted to provide a portion of an outer wall of the secure structure; providing a second structural layer adapted to provide a portion of an inner wall of the secure structure; and providing a first barrier layer between the first and second structural layers, the first barrier layer having a higher level of resistance to penetration than the first and second structural layers.

The method may further comprise the steps of enclosing the first barrier layer between the first and second structural layers and securing the first and second structural layers to one another with a suitable adhesive. The method may further comprise the step of enclosing lifting members between the first and second structural layers.

The method may further comprise providing a second barrier layer between the first barrier layer and the first or second barrier layers.

According to the present invention there is also provided a method of constructing a secure structure, the method comprising the steps of:-arranging a plurality of said security panels on top of and adjacent one another to provide a secure wall and or ceiling of the secure structure.

The method of constructing the secure structure may further comprise securing at least a portion of the plurality of security panels to one another with a fixing plate which extends between an edge of each security panel.

The method of constructing the secure structure may further comprise spacing the innermost structural layers of the security panels, and hence the security panels themselves, from each other with an internal divider member.

The method of constructing the secure structure may further comprise dividing the outermost structural layers of the security panels and hence the security panels themselves, from each other with an external divider member.

The method of constructing the secure structure may further comprise the step of concealing any external joins and attachment points from external view. The method may comprise covering the external divider member with a protective cap having outer flanges which extend past outer flanges of the external divider member.

The method of constructing the secure structure may further comprise the step of fastening the security panels to the internal divider with suitable fastening means which extend through the protective cap, packing material, external divider, fixing plate and into the internal divider.

Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying figures, in which: Fig. 1 is a partial cut away view of a first embodiment of an integrated security panel according to the present invention; Fig. 2A is a cross sectional side view of an upper section of the integrated security panel showing a tongue and groove profile provided thereon; Fig. 28 is a cross sectional side view of a lower section of the integrated security panel showing a tongue and groove profile and an elongated lip portion provided thereon; Figs. 2C and 2D are cross sectional views along opposite longitudinal edges of the integrated security panel; Fig. 3 is a cross sectional side view of an upper and lower security panel engaged with one another by fastening means to provide a column of security panels; Fig. 4 is a cross sectional top view of a pair of adjacent security panels I columns of security panels joined together by fastening means to secure them to a primary building structure; Fig. 5 is a more detailed view of a protective cap of Fig. 4 which covers the join between the adjacent panels I columns of security panels; Fig. 6 is a schematic orthogonal representation, and corresponding plan projection of a secure structure comprising a plurality of security panels arranged to provide secure walls; Fig. 7 is a further view of the structure of Fig. 6 further comprising security panels laid flat to provide a ceiling over an entry door of the secure structure; Figs. 8, 9, 10, 11 are cross sectional top views showing fixing means used to join the security panels together and to the primary building structure at various lateral locations around the secure structure progressing from a first wall end (Fig. 8) and first corner (Fig. 9) towards a second corner (Fig. 10), third corner (Fig. 11), a first door jamb (Fig. 12), to an opposing doorjamb (Fig. 13); Figs. 14 to 16 are cross sectional side views showing the vertical profile of the walls of the secure structure; Figs. 17 to 19 are various views of a second embodiment of an integrated security panel according to the present invention; and Figs. 20 and 21 are various views of a third embodiment of an integrated security panel according to the present invention.

Referring to Fig. 1, a security panel 100 is provided with an inner sheet 102 and an outer sheet 104 which together enclose an intermediate barrier layer 106. The sheets 102 and 104 each comprise a relatively thick mineral fibre structural layer 108 and 110 which are covered on both sides by relatively thin skin layers 112 and 114. In the embodiment shown, the outward facing skin layer 112 and the inward facing skin layer 114 comprise a layer of coated, galvanised steel.

As best illustrated in Fig. 2B and Fig. 3,the bottom of the outer sheet 104 has an elongated lip 116 and a pair of tongues 118, 119 extending downwardly therefrom. The outer skin layer 112 of the outer sheet 104 extends around the lip 116 and covers tongue 118, whereas the inner skin layer 113 of the outer sheet 104 covers tongue 119.

Referring to Fig. 2A, the top of the outer sheet 104 is shaped to provide a recess 130,8 pair of tongues 120,121 extending upwardly therefrom and a pair of grooves 122 and 123 therein. The outer skin layer 112 of the outer sheet 104 extends around and covers tongue 120 and groove 122, whereas the inner skin layer 113 of the outer sheet 104 covers tongue 121 and groove 123.

As best illustrated in Fig. 2B and Fig. 3, the bottom of the inner sheet 102 has a pair of tongues 124, 125 extending downwardly therefrom and a pair of corresponding grooves 126 and 127 therein. Skin layer 115 of the inner sheet 102 extends around and covers tongue 125 and groove 127, whereas skin layer 106 of the inner sheet 102 extends around and covers tongue 124 and groove 126.

Referring to Fig. 2A, the top of the inner sheet 102 has a pair of tongues 128, 129 extending upwardly therefrom. The skin layer 115 of the inner sheet 102 extends around and covers tongue 128, whereas the skin layer 106 of the inner sheet 102 covers tongue 129.

The security panels 100 may be produced on a rolling production line where they are cut from a roll of material. In the present embodiment this results in the longitudinal edges of the panels having tongue and groove formations provided thereon (as illustrated in Figs. 2C and 2D) and the square edges (the edges perpendicular to the longitudinal edges) being planar.

In the present embodiment the intermediate barrier layer 106 comprises a sheet of flattened, expanded steel arranged in a diamond pattern. The intermediate barrier layer 106 is slightly shorter than the overall height of the security panel 100. This provides a slot between the sheets 108, 100 which allows a fixing plate 132 to be received therein. As shown in Fig. 2C and 2D, as well as extending vertically between upper and lower adjacent security panels the fixing plate 132 also extends laterally between corners of adjacent security panels.

During fabrication of a security panel 100, the intermediate barrier layer 106 is laid between the inner sheet 102 and the outer sheet 104 such that the intermediate barrier layer is "sandwiched" therebetween. In this regard, a suitable adhesive is provided between the sheets 102, 104 in order to secure them together with the barrier layer 106. Both the diamond shaped arrangement of the barrier layer 106 and the roughened surfaces of the skins 114 and 113 further improve this adhesion. Although not shown in the present embodiment, lifting straps may also be compressed between the sheets 102, 104 to facilitate eventual manoeuvre of the resulting integrated security panel 100.

Construction of a secure wall comprising several of these security panels will now be described with particular reference to Figs. 1, 3, 4 and 5.

Referring to Fig. 3, a lower security panel 100A is first laid upright at an appropriate location for a secure wall. The fixing plate 132 is then slotted between sheets 102, 104 of the lower panel 1 OOA. Fastening means in the form of a fastening screw 134 is then driven through the front of the sheet 104 through a lower fixing hole in the fixing plate 132 and into the sheet 102 thereby securing the fixing plate 132 to the lower security panel bOA.

Upper security panel 1 OOB is then placed on top of the lower security panel 1 OOA such that the fixing plate 132 slots between the sheets 102 and 104 of the upper panel 1 OOB. A fastening screw 136 is then driven through a washer plate 141 and into the sheet 102, through an upper fixing hole in the fixing plate 132 and into the sheet 104 thereby securing the upper security panel 1 OOB to the lower security panel 1 OOA by way of the fixing plate 132. A shorter fastening screw 139 is also driven into the washer plate 141 through to the sheet 102 to further secure the upper and lower security panels to one another by way of the washer plate 141.

Note that as the upper security panel 1 OOB is brought into contact with the lower security panel 1 OOA, the tongue and groove profiles at the top of the lower security panel 1 OOA engage with the tongue and groove profiles at the bottom of the upper security panel 1 OOB as follows:-elongated lip 116 covers recess 130 (thereby concealing and preventing access to the head of fastening screw 134), tongues 118 and 119 are received within grooves 122 and 123, and tongues 128 and 129 are received within grooves 124 and 127. In this regard, the skins covering the tongue and groove profiles provide a degree of resilience which ensures that a tight and secure seal is provided therebetween (indeed this seal may be made virtually airtight if desired). The security panels 100A and 100B are therefore now stacked one on top of the other to provide a column of security panels.

As shown in Fig. 1 and Fig. 4, columns of security panels are arranged adjacent one another to form a secure wall. A first column of panels 1 OOC is secured to an adjacent column of panels 100D which are each, in turn, secured to a girder 138 of the primary building structure as follows.

A girder bracket 140 having a u-shaped channel running therealong is secured to the girder by a series of fastening screws 142 provided therealong. An internal divider beam 144 is then placed over the girder bracket 140 and secured with fastening screws 147.

A first column of panels 1 OOC is arranged against a flange on one side of the internal divider beam 144 and a second column of panels 100D are arranged against a flange on the other side of the internal divider beam 144 such that the internal divider beam 144 maintains the columns of panels adjacent one another in spaced relationship. Fastening screws 146 are then driven through the flange of the internal divider beam 144, sheet 104, fixing plate 132 and into sheet 102.

An external divider member 148 is then inserted into the space between the two outer sheets 104 and is secured to the internal divider member 144 by fastening screws 150 driven therethrough. Packing material 152 is then packed into the channel of the external divider member 148 over the heads of fastening screws 150. Fastening screws 154 are also driven through the flange of the external divider member 148, sheet 102, fixing plate 132, sheet 104, and out through the flange of the internal divider beam 140.

The adjacent columns of panels 100C and 100D are therefore now securely attached to the girder 138 and securely spaced relatively to one another; however, if they were to be left in this configuration, intruders would be able to access screw 154 and would also be able to easily access screw heads 150. As best illustrated in Fig. 5, a protective cap 156 having a u-shaped channel and flange edges 158 is therefore placed over the external divider member 148 to prevent such access. In this regard, the flange edges 158 extend outwardly to cover the flanges of the external divider member 148. The flange edges 158 are also bent back in on themselves at each end and are provided with a rubber gasket strip 160 which retains the flange edges 158 tight against the outer skin 112 of the security panel 100. Fastening screws 162 are driven through the u-shaped channel of the external divider member 148 at regular intervals therealong (although only one is visible in Fig. 1), packing material 152 and internal divider beam 144 in order to secure the protective cap 156 between the columns of panels 100C and 100D. The u-shaped channel of the protective cap 156 is also provided with a pair of recesses 164 therealong which allow a strip of resilient material 166 to be snap-fit or slid over the heads of fastening screws 162 from the top of the u-shaped channel.

With the security panels 100 arranged together as previously described an intruder cannot identify where the joins and screw heads are located without great difficulty. Furthermore, even if an intruder did have knowledge of the join and or screw head locations it would be very difficult for him to access them. It is therefore very difficult for the intruder to attempt unauthorised entry by attacking the joints of the structure.

Furthermore, if the intruder were to attempt to penetrate the mineral fibre core of the security panels 100 he would not be expecting the significant additional difficulty posed by the intermediate barrier layer 106 which would prevent him from penetrating the secure wall.

Construction of a secure structure comprising several of the previously described security panels 100 will now be described with reference to Figs. 6to16.

An example secure structure 200 is shown in Fig. 6 where several security panels 100 are arranged vertically and in Fig. 7 where several security panels 100 are arranged horizontally and laid flat on a ceiling section. The secure structures represented in Figs. 6 and 7 are mere representations of a possible structure with a selection of the various fixtures and fittings which may be required in an eventual secure structure. The reader will appreciate that certain features of the secure structure 200 may be selected in isolation depending upon the required application.

Referring to Figs. 8,9, 10 and 11, the connections provided on the walls of the secure structure 200 will now be described at various locations around the secure structure 200. In order to minimise repetition, similar features of the apparatus described subsequently have been numbered with a common two-digit reference numeral and have been differentiated by a third digit placed before the two common digits. Such features are structured similarly, operate similarly, and/or have similar functions as previously described unless otherwise indicated.

Referring to Fig. 8, at a first free end, generally designated A, a first security panel 100E is secured by a first girder bracket 1140 to a first girder 1138 by screws 1142. A fastening screw 202 is driven through the sheets of the security panel 100E into the first girder bracket 1140 to secure the panel thereto. A protective end cap 204 is placed around the ends of the panel 100E and is secured thereto by screws 206.

Referring to Fig. 9, at a first corner, generally designated B, the security panel 100E is secured to a second security panel 100F arranged perpendicular thereto. A second girder bracket 2140 is secured to a second girder 2138 by fastening screws 2142. A protective end cap 208 is placed over the tongue and groove profiles at the edge of the panel I OOE and is secured there by fastening screw 210 which extends through the sheets of the security panel 100E and into the girder bracket 2140.

In order to perpendicularly secure the security panel 1 OOF to the security panel 1 OOE, a u-shaped face bracket 212 is first secured to the security panel 100E by fastening screws 214. The security panel 100F can then be slotted into the face bracket 216 and then secured therein by fastening screws 214 driven through the sides of the face bracket 212 and into the sheets of the security panel 100F. A fixing plate 1132 may be provided between the sheets of the security panel 100F to improve this connection.

An L-shaped brace 213 is then secured at the intersection between the security panels 1 OOE and 1 OOF by fastening screws 216 in order to strengthen the joint between the security panels 1 OOE and 1 OOF.

Referring to Fig. 10, at a second corner generally designated C, a security panel 1 OOG (which is positioned at the end of a row of several columns of security panels) is secured to another security panel 100H arranged perpendicular thereto. In a similar fashion as the first corner B, a u-shaped end bracket 218 is first secured to the panel 1 OOG by fastening screws 220. A corresponding u-shaped end bracket 222 is also secured to the end of panel 100H. The two end brackets 218 and 220 are then secured to one another by fastening screw 224. An [-shaped brace 226 is then secured at the intersection between the panels 1 OOG and 1 OOH by fastening screws 228 in order to strengthen the joint between the panels 100G and 100E.

Referring to Fig. 11, at a third corner generally designated D, a security panel 1001 is secured to another security panel 100J in a similarfashion as previously described for corner C; however, an external brace plate 230 is provided to conceal screw heads 233 and provide greater strength to the outside of the resulting joint between the security panels. An internal brace 232 is also provided to strengthen the inside of the resulting joint.

Referring to Fig. 12, at a doorjamb generally designated E, the security panel 100J is provided with door post 234 attached by fastening screws 236. The door post 234 provides a frame for a door 238 to swing through a degree of movement indicated by arch A. An anchor post 240 is also attached to the inside of the security panel 100J to provided greater support. An external cover member 242 is attached to security panel 100J adjacent the door post 234 to conceal the heads of fastening screws 244.

As shown in Fig. 13 a similar doorjamb is also provided at the opposite side of the frame around door 238. Further fastening screws 246 are provided to secure the intersection between a corner panel lOOK and 100L with bracket member 248 at the adjacent corner generally designated F. An additional fastening screw 250 and fastening bracket 251 is also provided to secure this corner F of the secure structure 200 to a girder 139 of the primary building structure.

Referring to Figs. 14 to 16, the vertical profile rather than the /ateral profile of the various security panels of the secure structure 200 will now be described.

Fig. 1 4A illustrates the bottom of a horizontally arranged security panel (where the tongue and groove profiles point toward a foundation of the structure) attached to a secure foundation 300 comprising a foundation bracket 302 and an associated intermediate support member 304. The intermediate support member 304 is provided with a recess 1130 similar to that found on the top of each security panel 100 in order to provide the same concealed area behind elongated lip 116. Fig 14B shows a corresponding foundation bracket provided at the base of the secure door 238.

Fig. 15 shows the connection between a security panel 1 O1A forming a wall portion, and a security panel 101 B forming a ceiling portion of the secure structure 200. The security panels 101 A, 101 B are secured to one another with fastening screws and bracket plates similar to those previously described in relation to the corner section D. The panel 101 B attaches an internal support beam 201 and is supported by an internal bracket 203.

Fig. 16 shows the bottom of a vertically arranged security panel 100 (where the straight cut longitudinal edge of the security panel, rather than the tongue and groove profiles point toward the foundation) attached to a secure foundation 300 comprising a foundation bracket 302 and an associated intermediate support member 304. An intermediate protector plate 305 is also provided above the intermediate support member 304 to protect and conceal the fastening screw 307 there under.

In view of the previously described features an intruder will find external access to any of the fastening screws of the secure wall of Fig. 1 and the secure structure of Figs. 6 and 7 extremely difficult. For example, the protective cap 156 covers all otherwise accessible joints and fastening screws provided at the lateral join between the columns of panels 100. To defeat this, an intruder would need to prise a flange 158 away from the skin 112 and bend that flange sufficiently to gain access to the join or other fastening screws; however, this would be very difficult and time consuming to achieve due to the strength and resilience of the flanges 158 and the difficulty in gaining any purchase with a suitable tool.

Furthermore, it would be very difficult to gain access to fastening screws because of the presence of the resilient strip 166. In this regard, it would be very difficult to remove the strip 166 in view of its snap-fit engagement with the protective cap 156. Since all of these features also serve to conceal the location of the fastening screws the intruder is therefore unable to determine which part of the joint to attack.

Referring in particular to Fig. 3, as the upper security panel 100B is lowered onto the lower security panel I QUA, the elongated lip 116 covers recess 130 and hence covers the head of fastening screw 134. This also both prevents external access to the screw 134 and prevents an intruder from identifying the location of the screw 134. It also beneficially provides a flush edge at the join between the upper and lower security panels.

The fixtures and fittings provided around the wall of the secure structure also perform a similar dual function of concealing the fastening screws from view and restricting access thereto. See e.g. the L-shaped face bracket 212 (Fig. 9), L-shaped brace 226 (Fig. 10), external brace plate 230 (Fig. 11), and external cover members 242 (Figs. 12 and 13).

The fastening screws described above may also be provided with non-standard heads which require special tools to enable them to be fastened and unfastened.

Since the abovementioned features prevent attempted removal of the security panels 100 from the secure structure 200 an intruder may consider attempting to penetrate a security panel 100 itself with a drill or other tool. However, this would be unexpectedly difficult and time consuming because the intruder will not be expecting the security panel to have a "double thickness". Furthermore, they will not be expecting to encounter the intermediate barrier layer 106. The intermediate barrier layer 106 may confuse the intruder sufficiently to deter them from continuing. Furthermore, the intruder may not have equipment capable of penetrating the unexpected intermediate barrier layer 106 no matter how much time they spend attempting this.

Figs. 17 to 19 depict a second embodiment security panel generally referred to as 400. This is largely similar to the first embodiment described above, and corresponding features are simUarly numbered albeft prefixed with a "4" i.e. inner sheet 402 corresponds with inner sheet 102.

Where the second embodiment security panel 400 differs appreciably is in the provision of a second barrier layer 407. The second barrier layer 407 comprises a sheet of plywood material which is located between the first barrier layer 406 and the outer sheet 404. It will be understood that it is possible to place the second barrier layer 407 between the inner sheet 402 and the first barrier layer as an alternative.

In this embodiment, the plywood second barrier layer is 18mm thick and comprises four veneers bonded together in a known manner.

The advantage of the second barrier layer 407 is that it further mitigates the penetrability of the security panel 400, especially to intermittent blows from, for example, an axe. Under such an attack, the plywood second barrier layer 407 tends to reverberate due to its inherent resilience, and thus further mitigating penetrability in addition to simply providing an additional barrier layer to the first.

Figs. 20 and 21 depict a third embodiment security panel generally referred to as 500. This is largely similar to the first embodiment described above, and corresponding features are similarly numbered albeit prefixed with a "5" i.e. inner sheet 502 corresponds with inner sheet 502.

Where the third embodiment security panel 500 differs appreciably is in the provision of webbing straps WS. The webbing straps WS are loops of nylon strapping material which are fed through apertures in the expanded steel barrier layer 506, before the inner sheet 502 and an outer sheet 504 are bonded to it. The bonding secures the webbing straps WS in place.

The webbing straps WS provide a useful way of marioeuvring the security panel 500 into place by crane or other lifting apparatus, or even simply manually. They may be cut off once the panel 500 is installed.

It will be understood that such webbing straps may be employed with security panels similar to the second embodiment 400 i.e. those with a second barrier layer provided.

It will be understood that although described in relation to forming internal structures within buildings, the present invention may also be used to form external structures themselves.

Modifications and improvements may be made to the foregoing without departing from the scope of the invention; for example, the thickness of the barrier layers may be varied from that described above.

Moreover, the orientation of the mineral wool core may change from slabs with generally horizontally oriented fibres to mineral wool slabs with vertically oriented fibres.

Further, there may be possible variations to the driving heads of the screws to add additional proof against attack.

Claims (1)

1. <claim-text>Claims 1. A security panel comprising a plurality of integrated panel layers, the panel layers comprising:-a first structural layer adapted to provide a section of an outer wall of a secure structure; a second structural layer adapted to provide a section of an inner wall of a secure structure; and a first barrier kyer provided between the first and second structural layers, the first barrier layer having a higher level of resistance to penetration than the first and second structural layers.</claim-text> <claim-text>2. A security panel according to claim 1 further comprising a second barrier layer. (\Jis</claim-text> <claim-text>3. A security panel according to daim 2 wherein the second barrier layer is O provided between the first barrier layer and the first structural layer.</claim-text> <claim-text>0 4. A security panel according to claim 2 wherein the second barrier layer is provided between the first barrier layer and the second structural layer.</claim-text> <claim-text>S. A security panel according to any preceding claim wherein the first barrier layer is ribbed and / or perforated to provide a roughened surface.</claim-text> <claim-text>6. A security panel according to any of claims 2, 3 or 4 or claim 5 when dependant on claim 2, 3 or 4 wherein the second barrier kyer is ribbed and / or perforated to provide a roughened surface.</claim-text> <claim-text>7. A security panel according to any preceding claim wherein the first and second structural layers are provided with engagement means at either end to allow a first security panel to be engaged with a second security panel such that the resulting first and second engaged security panels form a portion of a secure wall.</claim-text> <claim-text>8. A security panel according to claim 7 wherein the engagement means comprises tongue and groove profiles provided at either or both ends of the security panel.</claim-text> <claim-text>9. A security pane' according to claim 8 wherein the tongue and groove profiles comprise a pair of grooves provided at the top of the first structural member and a pair of tongues provided at the bottom of the first structural member, a pair of tongues provided at the top of the second structural member and a pair of grooves provided at the bottom of the second structura' member.</claim-text> <claim-text>10. A security panel according to any preceding claim wherein at least one of the first or second structural layers is provided with an ethngate member at its lower end and a corresponding recess at its upper end in order to provide a concealed channel therebetween when the first and second security panels are engaged to (\.J 15 form a secure wall. r</claim-text> <claim-text>0 11. A security panel according to any preceding claim wherein the first and second structural layers comprise a layer of mineral fibre material having a O thickness of between 60mm and 200mm.</claim-text> <claim-text>12. A security panel according to any preceding claim wherein the first and second structural layers include a relatively thin skin layer.</claim-text> <claim-text>13. A security pane' according to claim 12 wherein the skin layer comprises a layer of coated steel.</claim-text> <claim-text>14. A security panel according to daim 12 or 13 when dependant on claim 8 wherein portions of the skin layer extend around the surfaces of the tongue and groove profiles to facilitate engagement with each other when a first security panel is engaged with a second security panel.</claim-text> <claim-text>15. A security panel according to any preceding claim wherein the first barrier layer comprises a lattice structure.</claim-text> <claim-text>16. A security pane' according to claim 15 wherein the lattice structure is provided by a flattened) expanded steel sheet.</claim-text> <claim-text>17. A security panel according to any of daims 2, 3 or 4 or claims 5 to 16 when dependant on claim 2) 3 or 4 wherein the second barrier layer comprises a hminar structure.</claim-text> <claim-text>18. A security panel according to any of claims 2, 3 or 4 or claims 5 to 17 when dependant on claim 2, 3 or 4 wherein the second barrier layer comprises a plywood materiaL (\.J 15 19. A security panel according to any preceding claim wherein adhesive is be provided between the first and second structural layers in order to secure the first 0 and second structural layers together and to enclose the barrier layer(s) v" therebetween.20. A security panel according to any preceding claim wherein lifting members may be a'so be clamped between the first and second structural layers to assist handling of the resulting security panel.21. A security panel according to any claim 20 wherein the lifting members comprise lifting straps.22. A secure structure comprising a plurahty of security pands according to any preceding claim arranged to provide a secure structure, the plurality of security panels being arranged adjacent and on top of one another to form wafls and/or ceilings of the secure structure.23. A secure structure according to claim 22 wherein at least a portion of the plurality of security panels may be secured to one another by a fixing plate extending between each security panel.24. A secure structure according to claim 23 wherein the fixing plate is adapted to be inserted in a slot provided between the first and second structural members of first and second adjacent security panels.25. A secure structure according to claim 24 wherein fastening means are provided to pass through portions of the fixing plate in order to secure adjacent panels.26. A secure structure according to claim 25 wherein the fastening means comprises a plurality of fastening screws. \Jisr 27. A secure structure according to any of claims 22 to 26 wherein the secure 0 structure is provided with an internal divider beam which engages with innermost structural layers of the security panels to retain adjacent co'umns of security panels 0 in spaced relationship with one another.28. A secure structure according to claim 27 wherein the internal divider beam has a u-shaped ridge which is received within a gap between the columns of adjacent security panels.29. A secure structure according to any of claims 22 to 28 wherein an external divider member is provided which engages with outermost structura' layers of the security panels.30. A secure structure according to claim 29 wherein the externa' divider member comprises a u-shaped Thngitudinal channel having outer flanges which mate with a portion of the outermost skin of the structura' member.31. A secure structure according to claim 29 or 30 wherein packing material is provided in the u-shaped channel of the external divider member.32. A secure structure according to any of claims 29 to 31 wherein a protective cap is provided to cover the external divider member and thereby conceal the joint between columns of adjacent security pane's.33. A secure structure according to claim 32 wherein the protective cap comprises a u-shaped longitudinal channel adapted to be received within the u-shaped channel of the external divider member.34. A secure structure according to claim 32 or 33 wherein the protective cap comprises outer flanges adapted to extend past outer flanges of the externa' divider member, and are inwarthy bent in order to provide gasket edges which mate with (%.J 15 the externa' skin of the outermost structural layer to prevent access to the join between adjacent columns of security panels.35. A secure structure according to claim 34 wherein the gasket edges are 0 provided with resilient sealing means in order to maintain tension against the skin of the outermost structural layer.36. A method of constructing an integrated security panel for use in constructing a secure structure, the method comprising the steps of:-providing a first structural layer adapted to provide a portion of an outer wafl of the secure structure; providing a second structura' layer adapted to provide a portion of an inner wah of the secure structure; and providing a first barrier layer between the first and second structura' layers, the first barrier layer having a higher level of resistance to penetration than the first and second structural layers.37. The method of claim 36 further comprising the steps of enclosing the first barrier layer between the first and second structural layers and securing the first and second structural layers to one another with a suitable adhesive.38. The method of claims 36 or 37 further comprising the step of enclosing lifting members between the first and second structural layers.39. The method of any of claims 36 to 38 further comprising the step of providing a second barrier layer between the first barrier layer and the first or second structural layers.40. A method of constructing a secure structure, the method comprising the steps of:-arranging a plurality of security panels according to any of claims 1 to 35 on C\J 15 top of and adjacent one another to provide a secure wall and/or ceiling of the secure 1 structure.41. The method of claim 40 further comprising securing at least a portion of the 0 plurality of security panels to one another with a fixing plate which extends between an edge of each security panel.42. The method of claims 40 or 41 further comprising spacing the innermost structural layers of the security panels, and hence the security panels themselves, from each other with an internal divider member.43. The method of any of claims 40 to 42 further comprising dividing the outermost structural layers of the security panels and hence the security panels themselves, from each other with an external divider member.44. The method of any of claims 40 to 43 further comprising the step of concealing any external joins and attachment points from external view.45. The method of any of claims 40 to 44 further comprising covering the external divider member with a protective cap having outer flanges which extend past outer flanges of the external divider member.46. The method of claim 45 further comprising the step of fastening the security panels to the internal divider with suitable fastening means which extend through the protective cap, packing material, externa' divider, fixing ptate and into the internal divider. (4 r Ce)</claim-text>