MXPA96004326A - Improvements in and related to composite door coating panels - Google Patents

Abstract

The present invention relates to a double coating composite panel comprising two steel facing plates (2, 3) of a thickness between 2 millimeters and 32 millimeters joined together by transverse members (1). Each transverse member (1) is generally aligned perpendicular to the facing plates and is spaced from its adjacent members by a distance of between 10 and 80 times the thickness of the center of the facing plates (2, 3) the spacing between the facing plates being between 30 millimeters and 800 millimeters. A filling or loading material, eg, concrete, is introduced into the separation between the plates.

Description

"IMPROVEMENTS IN AND RELATED TO COMPOSITE DOUBLE COATING PANELS" This invention * relates to double-skin composite panels comprising a layer of a filler or filler (usually a cementitious material such as concrete) coated with plates (usually carbon steel) and methods to produce them. A lighter filler or filler such as a synthetic resin loaded may be used for certain applications. The double-coated composite panels exhibit characteristics similar to those of reinforced concrete structures and are advantageous as the facing plates act as reinforcements to allow the required strength characteristics to be achieved with lower total depth structures than that of the reinforced concrete. High reinforcing ratios are possible and the plates act as a permanent seal for the central concrete layer. Double-layered composite panels are known comprising two steel facing plates placed on each side of a concrete layer and connected thereto by transverse members which extend generally perpendicular to and are fixed at their ends to both facing plates. These panels are disclosed in the Patent Numbers GB-A-2136032, GB-A-2136033 and GB-A-2258669. Up to now, these double clad composite panels have been produced in situ, that is, at the site where the main sub-structures are to be installed or assembled. During on-site production, not only is the amount of on-site management required doubled because each liner is handled separately but also significantly increases panel production costs. Generally, these known panels comprise a combination of relatively thick facing plates, internal ties and face plate stiffeners. They also require external support and / or internal stiffeners for the facing plates during the casting of concrete between the plates to avoid structural distortion caused by high hydrostatic pressures produced during casting. It has also been found necessary to limit the height from which or the rate at which the concrete is poured to reduce these pressures. The double-skin composite panels of the present invention are intended to be produced at the factory and supplied to the site as integral structures comprising facing plates secured together by transverse connecting members. The plates can be flat or curved. The dimensions of the panels according to the invention are such that they are rigid enough to retain their configuration during handling in order to allow large structures to be assembled quickly and accurately. Individual panel sizes up to 3.5 meters wide by up to 18 meters long are feasible, minimizing construction time at the site. The relatively narrow separation of the transverse connecting members allows the concrete to creep up to high loads without distorting the structural configuration of the panel and without the need for internal reinforcement or external shoring. The panels in accordance with this invention allow double-layer composite structures to be constructed in thicknesses that have hitherto been impractical. The tests and experiments carried out by the applicants have shown that, for most panels of double coating compounds of potential commercial interest, there are limits that must be placed on the thickness of the facing plate, separation of the plate and separation of the plate. transverse member if the required panel strength and handling capacity is to be achieved. Also, that each cross member must be secured to both facing plates, preferably by welding, with its longitudinal axis essentially perpendicular to the generally parallel facing plates. These tests have also established that panels having transverse connecting members fixed to both faceplates have greater strength than conventional structures having overlapping shear studs. Therefore, applicants have established that for panels of a width of 1 meter to 3.5 meters and a length of 2 meters to 18 meters, the spacing between the adjacent transverse members is important, inter alia, to prevent sagging of the plates away from the filling or loading material (usually concrete). If this separation is too large, there is a high possibility of warping occurring. Applicants have also established that there is a relationship between the thickness of the plate and the cross member spacing that must be followed to achieve the required handling capacity and strength characteristics. Likewise, the applicants have determined a scale of steel plate thicknesses that provide the required strength characteristics without increasing the weight and handling capacity of the panels.

The Patent Number GB-A-2136033 discloses that the spacing between the transverse members of a double-skin composite panel is preferably equal to the spacing between the facing plates of the panel. Also, that the spacing between the transverse members can be as large as up to four times the spacing between the facing plates but advantageously it is less than twice this spacing. Neither Patent Number GB-A-2136032 nor GB-A-2258669 discloses which are the desirable separations. The present invention discloses the manner of providing double-skin composite panels having the characteristics discussed above. By the term "double-coated composite panel" is meant a panel comprising two generally parallel facing plates joined together by a plurality of cross-members placed in a plurality of separate and aligned rows generally perpendicular to the facing plates, the interior of the panel loaded with a filling or loading material, eg, a cementitious material such as concrete. According to the present invention there is provided in one aspect a fabricated double-skin composite panel comprising two facing plates of a thickness of between 2 millimeters and 32 millimeters joined together by transverse members each aligned generally perpendicular to the facing plates and separated from its adjacent members by a distance of between 10 and 80 times the thickness of the facing plates, the separation between the facing plates being between 30 millimeters and 800 millimeters. In a preferred construction, the transverse members are each connected to both facing plates. The transverse members may take the form of bars, tubes, continuous tapes or the like. Preferably, the width of the panel is between 1 meter and 3.5 meters and the length of the panel is between 2 meters and 18 meters. The thickness of each facing plate can be between 3 millimeters and 20 millimeters. Alternatively, this thickness can be between 6 millimeters and 20 millimeters. The separation between the facing plates can be between 100 millimeters and 800 millimeters. Alternatively, the separation can be between 150 millimeters and 800 millimeters. In one arrangement, the spacing between the adjacent transverse members is within the range of 10 to 60 times the thickness of the facing plates. In other arrangements, this separation is between 10 and 50 times the thickness of the facing plates or from 15 to 50 times this thickness. In a preferred arrangement, this scale is between 20 and 40 times the thickness of the facing plate. The double-skin composite structures are assembled from a multiplicity of individual panels, each panel being welded to its adjacent panel or panels. Preferably, the ends of each transverse member are welded to the facing plates. Alternatively, the connection between some or all of the transverse members may take the form of a pin and plug connection where in one arrangement, the ends of the transverse member, each is formed with a deformable pin or plug, a corresponding plug or pin (as the case may be), making sure on the inner surface of the metal plates of the panel. The plug may comprise a suitable dimensioned recess or recess formed in the facing plate. The pin is preferably of convergent cross section and defines a frictional fit within the opening or recess. Alternatively, each transverse member can be welded at one end to the inner surface of one of the facing plates and can be formed at its other end with a pin or plug, the pin or the plug respectively cooperating with a pin or plug secured to the surface internal of the other metal plate of the structure. For assembly purposes, each facing plate may have secured to its inner surface a plate formed with a generally flat or profiled section and an inclined end section, the inclined end section acts as a guide when the panel is aligned with the adjacent double facing composite panel which will be soldered. In a preferred arrangement, the plate takes the form of a reinforcing backing plate which is secured along and protrudes from one side of an inner face of each panel, the plates being secured to the internal faces of the respective panel and each one including a first section of a length that overlaps the spacing between the adjacent panels and an end section that is inclined inward toward the respective panel center. In another aspect, therefore, an apparatus is provided for use when the adjacent double-skin composite panels of a double-skin composite structure are assembled together, the apparatus comprising a backing plate secured along and protruding from one side of each internal face of each panel, the plates are secured on the internal faces of the respective panel and each includes a first section of a length that overlaps the spacing between adjacent panels and an end section that is inclined inward toward the center of the respective panel. During the welding of the adjacent panels, each backing plate can cooperate with a movable shoe above the adjacent edges of the outer faces of the adjacent panels to define with the plate a mold for retaining the liquid metal produced during the welding operation . In a s further aspect, a backing plate comprising a profiled or generally planar section and an inclined end section, the generally planar or profiled section being capable during the use of defining a wall of a weld metal deposit, is provided, and the inclined end section acts in cooperation with the inclined section on the opposite face as a guide for placing together the adjacent panels of a composite double-faced structure. The transverse members may be steel bars of essentially uniform cross-section along their entire length. Alternatively, the bars may be of "I" or "T" section. The facing plates can usually be flat or curvilinear.

The invention will now be described by way of example only with reference to the accompanying diagrammatic drawings, in which: Figure 1 is a perspective view of a double-skin composite panel in accordance with the invention; Figure 2 is an enlarged side view of the panel shown in Figure 1; Figures 3 and 4 are side views of alternative transverse members for use in the panels shown in Figures 1 and 2; Figure 5 illustrates diagrammatically an assembly of a double-skin composite structure of a multiplicity of double-skin composite panels as illustrated in Figures 1 to 4; Figure 6 is a plan view from above two adjacent double clad composite panels ready to be welded together; Figure 7 is a view of adjacent panels during welding; Figure 8 illustrates a spacer for use with the illustrated apparatus; and Figures 9 to 12 are side views of alternative transverse members of the panels according to the invention.

The double-skin composite panel illustrated in Figures 1 and 2 comprises a plurality of separate steel cross members 1, each welded at each end to the inner surfaces of the steel facing plates 2, 3. The transverse members 1 are placed perpendicular to the faceplates and may comprise continuous bars, tubes or tapes. For reasons of simplification, the transverse members will be referred to below as bars. To complete the structure, the gap between the plates is filled with a cementitious material, e.g., concrete 5 normal or lightweight. By doing this, the bars 1 are embedded in the concrete. As illustrated, the bars 1 are welded between the flat plates. Sometimes, however, it is necessary to weld the bars between the plates that have a single curvature. During use, the panels in accordance with the invention are subjected to various forces and stresses which, unless accommodated, can result in panel failure during use. Applicants have determined that faults in a wide range of panel sizes can be avoided or at least minimized by ensuring that the thickness of the facing plate, the spacing of the bar and the spacing of the bars are within the scales specified in the foregoing. Therefore the Applicants have established that for panels of a size 1 meter by 2 meters up to 3.5 meters by 18 meters, the thickness of the steel facing plates must be within the scale of 2 millimeters or 32 millimeters. Likewise, the separation between the frontal plates 2, 3 must be 30 millimeters and 800 millimeters, and the center of each bar must be separated from the centers of the adjacent bars by a distance equal to between 10 and 80 times the thickness of the bars. plaques. The preferred separation scales are between 10 and 60, 10 and 50, 15 and 50 times and 20 and 40 times the thickness of the facing plates. As shown, the transverse members 1 are welded on the plates 2, 3 at the centers forming a predetermined pattern and the spacing between the adjacent transverse members must be between 20 and 50 times the thickness of the plate. The cross members, however, do not need to form any specific pattern. The bars 1 illustrated in Figures 1 and 2 are generally cylindrical. There may be occasions, however, when bars in the form of "I" or "T" are preferred. This bar is illustrated in Figure 3.

The "I" section connecting member illustrated in Figure 3 includes a vertical ribbon 6 and an end flange 7 (only one of which is shown). The member is secured in each steel plate 2, 3 steel encased by the welds 9, and the interface of each continuous tape and the flange is provided with a radius 10. The concrete introduced between the faceplates and around the connecting members generates Compression force that usually act in the direction of Arrow C towards the angle between the connecting members. The predominant part of the vertical component of these compression forces as shown in Figure 3, it goes directly towards the tabs 7 by pushing the tabs 7 towards their desired contact with the front plates. Tension and bending forces are still generated at the intersection of the continuous belts 6 and the flanges 7, but these do not act at the site of the respective welds 9. The radius 10 greatly reduces the stress concentration factors. In the arrangement shown, the welds 9 are mainly loaded with a shear stress in a limited amount of direct tension. Therefore, a greatly reduced and / or lower quality welding can be employed. Also, for the rods, the length of the weld is increased significantly thereby further reducing the weld stresses. In the arrangement illustrated in Figure 4, each flange 7 is formed with stepped side portions 12 and a central depression 11, its contact with the adjacent faceplate being limited to the stepped side portions 12. This construction of the connecting member can be usefully used when the member adopts the shape of a bar to be welded on adjacent facing plates by a resistance or friction welding technique. Turning now to Figure 5 of the drawings, as shown in the panels, as described above with reference to Figures 1 and 2, they are assembled together to produce a composite double-skin structure using, for example, a crane 14. Since a panel is positioned in position by the crane 14, it is welded to its adjacent panel or panels to produce a double-coated composite structure of the required configuration and dimensions. It will be seen from Figure 6, secured on each of the internal surfaces of the two plates 2, 3 facing there is a backing plate 15. The plate 15 can be secured, for example by welding or by means of an adhesive. The backing plate 15 is produced, for example, from carbon steel. Each backing plate 15 includes a generally flat or appropriately profiled section 16 which overlaps the required spacing 17 between the adjacent panels. The backing plates 15 also include inwardly inclined sections 18 which act to assist alignment of the adjacent panels during assembly of the structure. Therefore, the inwardly inclined sections 18 enter and provide guides to allow the backing plates 15 of a panel to enter the adjacent side of the neighboring panel in an appropriate manner in order to align the panels with respect to each other. The inclined sections 18 can be formed with holes to allow cement to flow from one side of the backing strip to the other during the filling operation. As will be seen from Figure 7, during welding the generally flat section 16 of each backing plate defines a side of a reservoir for retaining the molten solder metal produced by resistance heating of the welding consumables. The other side of the respective reservoir is defined by a shoe 19 cooled with water that moves upwardly above the outer faces of the sides of the panels, in a conventional manner. Typically welding is effected by an electrically conductive slag technique. As illustrated in Figure 8, a spacer 20 can initially be placed within the spacing between adjacent panels for alignment purposes and to ensure a minimum width for welding. These separators 20 can be removed and consumed during the welding process. Figures 9 to 12 illustrate alternative shapes of the transverse members. The transverse member illustrated in Figure 9 takes the form of a steel tie bar 21 welded at one end to the face plate 2 which is formed at its other end with a plug 22. A steel pin 23 is welded on the plate 3 and is dimensioned to define a frictional fit within the interior of the plug 22. As will be seen from this Figure, the pin tapers inward from its base for ease of initial placement of the plug above the pin, then applying to one or both of the steel plates to push the pin over the plug to provide a mechanical friction connection between the pins. same. Therefore, as the pin enters the socket, the latter expands radially to create high radial forces and mobilize friction. Typically the pin and socket are produced by machining or a cold forging process. Turning now to the arrangement illustrated in Figure 10, the connector in this embodiment comprises a transverse member in the form of a tubular (or partially tubular) tie bar 24 whose open ends extend above and deform by the pins. insured in each plate 2, 3 front. In Figure 11, the illustrated transverse member comprises a tie bar 26 whose ends define the pins 27 which extend toward and deform the plug 28 secured in each faceplate. Only one end of the bar 26 can define a pin, the other comprising a plug or simply welding to the other facing plate. In Figure 12, a steel pin 29 is dimensioned to define a frictional fit within the interior of a plug 30. In this embodiment, the plug comprises an aperture configured in the face plate 2. The cross section of the pin 29 tapers to assist location of the pin within the opening and to ensure a good frictional fit between the pin and the face plate 2. The steel pin 29 can be formed with an internal collar 31 (shown in broken line) that abuts against the inner face of the steel plate 2. The pin can extend to the outer face of the plate 2 or can be placed from the surface to define a recess in order to receive a welding cap. In an alternative arrangement, the pin extends through the opening and carries external screw threads to receive an internally threaded nut that, in essence, replaces the previously described plugs. The clamping force between the pins and the plugs can be increased by the use of an adhesive such as a slow solid epoxy resin which has the additional advantage of acting as a lubricant during assembly. The expanded adhesive does not necessarily have to solidify quickly immediately since there will be sufficient mechanical interlacing between the pins and the plugs to allow the panels to be handled immediately. Alternatively, or additionally, the epoxy resin charged with very fine particles (for example submicron size) of a very hard substance such as silicon carbide or aluminum carbide, can be employed of course. As explained above, during assembly the epoxy resin acts as a lubricant, the excess of the epoxy resin being removed from the joint by high radial forces generated during assembly. The discrete particles are embedded in the steel interfaces of the pin and plug connectors as the radial force is transferred to be carried through the particles before the solidification of the epoxy resin. The subsequent application of a tension load acting in one direction to pull the plug pin outward, mobilizes an "earth-like" interaction as the interface cutting shear is transferred from one embedded particle to the other. In addition, or alternatively, a compound charged with welding or heavy solder powder can be applied to the external faces of the pins and / or the internal faces of the plug. These compounds act as lubricants during assembly and, when subjected to heating, the solder or brazing metal melts and during subsequent cooling solidifies to define a high capacity joint or weld soldered with simple or strong solder. Additionally, or alternatively, an anti-lubricating agent that acts to remove the oxide layer from the surface of the metals can be applied to the surface of the pin or plug. Placing the matching surfaces together results in an intimate metal-to-metal contact resulting in a series of cold-press welds and mechanical entanglements providing an almost original metal resistance connector. It will be appreciated that the foregoing is only exemplary of the apparatus in accordance with the invention and that modifications can easily be made therein without departing from the true spirit of the invention as set forth in the appended claims.

Claims (34)

CLAIMS:

1. A prefabricated double-skin composite panel comprising two facing plates of a thickness of between 2 millimeters and 32 millimeters joined together by transverse members each aligned generally perpendicular to the facing plates and spaced apart from their adjacent transverse members by a distance between 10 and 80 times the thickness of the centers of the facing plates, the separation between the facing plates being between 30 millimeters and 800 millimeters.

2. A panel according to claim 1, wherein each transveresal member is connected at its ends to both facing plates.

3. A compliance panel With the claim 1 or claim 2, wherein the facing plates are produced from steel.

4. A panel according to any of claims 1 to 3, wherein the transverse members are produced from steel.

5. A panel according to any of the preceding claims, wherein the thickness of each facing plate is between 3 millimeters and 20 millimeters.

6. A panel according to any of the preceding claims wherein the thickness of each facing plate is between 6 millimeters and 20 millimeters.

7. A panel according to any of the preceding claims, wherein the separation between the facing plates is between 100 millimeters and 80 millimeters.

8. A panel according to any of the preceding claims, wherein the separation between the facing plates is between 150 millimeters and 800 millimeters.

9. A panel according to any of the preceding claims, of a width of between 1 meter and 3.5 meters and a length of between 2 meters and 18 meters.

10. A panel according to any of the preceding claims wherein the spacing between the adjacent transverse members is within the range of 10 to 60 times the thickness of the facing plates.

11. A panel according to claim 10, wherein the spacing between the adjacent transverse members is within the range of 10 to 50 times the thickness of the facing plates.

12. A panel according to claim 10, wherein the spacing between the adjacent transverse members is within the range of 15 to 50 times the thickness of the facing plates.

13. A panel according to claim 10, wherein the spacing between the adjacent transverse members is between 20 and 40 times the thickness of the facing plate.

14. A panel according to any of the preceding claims, wherein the transverse members are welded to the facing plates.

15. A panel according to any of claims 1 to 13, wherein each transverse member is connected to one or both of the facing plates by a pin and plug connection.

A panel according to any of the preceding claims, wherein each facing plate is secured to its inner surface on one or more edges or edges, a backing plate formed with a generally flat or profiled section and an end section inclined able to act as a guide during the assembly of the panel in an adjacent panel.

A panel according to claim 16, whereby the backing plate is secured along and protrudes from one side of each inner face of each panel, the backing plates are secured on the internal faces of the respective panel and each includes a first section of a length extending beyond the end of the panel, and an end section that is inclined inward toward the center of the panel.

18. A double-coated composite panel comprising two facing plates connected together by a plurality of transverse members, each facing plate being secured to its inner surface, a backing plate formed with a generally flat or profiled section and an inclined end section, the inclined end section acts as a guide when aligning the panel with a double facing composite panel adjacent to which it is to be welded.

19. A backing plate comprising a generally planar or profiled section and an inclined end section, the generally planar or profiled section is capable, during the use of defining a wall of a weld metal tank and the inclined end section it acts in cooperation with the inclined section on the opposite face as a guide for arranging the adjacent panels of a double-coated composite structure together.

20. A panel according to any of the preceding claims, wherein each transverse member comprises a steel bar.

21. A panel according to claim 20, wherein each steel bar is of essentially uniform cross section along its entire length.

22. A panel according to claim 20, wherein each steel bar is of an "I" or "T" section.

23. A double-skin composite panel according to claim 1, wherein the transverse members are connected to the facing plates by connections comprising a pin or plug welded to the inner surface of one or both metal sheets and a plug or socket. complementary pin carried by one or both ends of the transverse members and sized to receive the pin or for insertion into the plug of the adjoining face plate.

24. A panel according to claim 23, wherein the pin and / or plug is deformable during assembly.

25. A panel according to claim 23 or claim 24, wherein the plug comprises a properly dimensioned hole or recess formed in one or each facing plate.

26. A panel according to any of claims 23 to 25, wherein the pin is of convergent cross section and defines a frictional fit between the opening or recess.

27. A panel according to any of the preceding claims, wherein the facing plates are generally planar.

28. A panel according to any of the preceding claims, wherein the facing plates are generally curvilinear.

29. A method for producing a structure of a plurality of double-skin composite panels according to any of claims 16 to 19, the method includes the step of placing the inclined end sections of the backing plates of a panel within the open end of the adjacent panel with the first sections of the backing plate closing the inner side of the separation between the panels.

30. A method according to claim 29, wherein the first section of each backing plate defines a wall of a mold for retaining the liquid metal produced during welding together of the adjacent edges or edges of the panels.

31. A double clad composite panel essentially as described above and as described with reference to Figures 1 and 2 of the accompanying drawings.

32. A double clad composite panel essentially as described herein with reference to Figures 3 and 4 of the accompanying drawings.

33. An assembly of a double-clad composite structure of a multiplicity of double clad composite panels essentially as described herein with reference to Figures 5 to 8 of the accompanying drawings.

34. A double clad composite panel essentially as described herein with reference to Figures 9 to 12 of the accompanying drawings.