GB2130268A - Mesh panel formwork - Google Patents

Abstract

Buildings are constructed from prefabricated panels comprising a metal frame (20) infilled with metal mesh (18). These panels are bolted into long structural members (42, 48) at top and bottom. The bottom structural members (42) may have downwardly projecting joggles (44) by means of which they are concreted into the foundations. When the prefabricated parts have been built up the resulting open structure is coated with concrete. <IMAGE>

Description

SPECIFICATION Structures This invention relates to prefabricated parts for use in constructing buildings, and to a method of building using such parts.

The present invention provides a system of prefabricated parts which can be factory built.

These are transported to the site and erected to give a structure which is then clad with concrete at the site. It is possible, and preferred, to make the prefabricated parts light in weight, greatly facilitating transport and erection. The application of concrete can all be done at the site. Preferred forms of the invention can give a building with good strength against hurricane and earthquake.

The system of parts of this invention comprises panels and elongate structural members attachable to top and bottom regions of these panels. Preferably the parts also include prefabricated roof trusses, and also purlins. The panels consist of a metal frame infilled with mesh or another perforate sheet material. This mesh or sheet is such as to be capable of being coated with concrete. The preferred mesh material is expanded metal mesh, a known material formed by punching metal sheet so as to slit and distort it into a mesh, without punching out waste.

The panels and the structural members are all provided with bolt holes (or some other fastening means) enabling them to be connected together at the points defined by these bolt holes (or other fastening means).

Preferably the structural members attachable to top and bottom regions of the panels are channel sections, and it is preferred that the bottom channels have projections from the channel base to act as joggles embedded in foundation concrete.

Roof trusses are preferably made from metal angle section lengths paired together to give a T section. This form of construction can give a lightweight truss of adequate strength.

The invention embraces such prefabricated roof trusses, also bottom channels and the panels themselves; it also embraces methods of building using the system of parts. The various aspects of the invention are set forth specifically in the patent claims which follow.

The invention will be more fully explained, and various preferred features disclosed, by the following description of an embodiment.

This is an example only, and is described with reference to the accompanying drawings in which: Figure 1 is an elevational view of a first building panel; Figures 2 and 3 are elevational views of further building panels; Figure 4 is a detail of one corner of a panel; Figure 5 illustrates the joining of panels at a corner of a building; Figure 6 is an exploded view which illustrates the connection of an internal wall; Figure 7 is a perspective view of bottom channels on a blockwork foundation; Figure 8 is a vertical section through such a channel and foundation; Figure 9 is a sectional view of a panel inserted between top and bottom channels; Figure 10 is an elevational view of a roof truss; Figure ii is a detail view of the lower part of a roof truss on a wall; Figure 12 is a section through a purlin; and Figure 13 is a diagrammatic view of a partially completed building.

Referring to the drawings, Figs. 1, 2 and 3 of the drawings show three types of prefabricated building panels 2, 4, 6 used in forming a building structure. All three panels have the same overall dimensions of 4ft wide X 8ft high, and are constructed in a similar way.

Each is formed from two frames with a sheet 1 8 of 14 inch diamond-raised expanded metal mesh sandwiched between them. Each frame is formed from lengths of 7/8 inch by 7/8 inch 1 6 swg mild steel angle section and the mesh is made from 20 swg steel sheet. As can be seen from Figs. 4 and 9, each length of angle section 20 has a web 22 lying against the mesh 1 8 and a second web 24 projecting outwardly from it.

For the panel 2, the frame on one face of the mesh 1 8 surrounds its periphery and also has a central upright and cross members (all of angle section) as shown in Fig. 1. The frame at the opposite side face also surrounds the periphery of the panel but may omit some or all of the cross members. Construction is by welding. The first mentioned frame is assembled in a jig, the metal mesh 18 is laid on it and then the second frame, previously assembled in a separate jig, is laid on top and the two frames and the mesh welded together.

Bolt holes 28 are provided in the webs 24 around the periphery of the panel. These holes are provided close to the corners, and at either side of the mesh, as shown in Fig. 4.

Further bolt holes (not shown) are provided intermediately along each edge of the panel.

The panels shown in Figs. 2 and 3 are constructed similarly from the same materials.

However, the panel shown in Fig. 2 is constructed so as to leave a door opening 30 and the panel shown in Fig. 3 is constructed so as to leave a window opening 32. As mentioned, the panels have the same overall size; they are provided with bolt holes 28 in exactly corresponding positions with the result that any one of the three panels can be fitted at the same position in a structure. These three panel types between them are enough to enable provision of doors, windows and plain walls in the building. Of course further panels of the same size but with a different size window opening could be provided if desired.

After fabrication of the panel 4 shown in Fig.

2 a steel door frame (not shown complete with hinges is welded into the opening provided. Similarly, a steel frame carrying window louvres is fitted into the aperture provided for it in the panel 6 of Fig. 3.

Figs. 7 and 8 iilust;rite the making of a foundation at the building site. A conventional foundation trench 34 is dug, and a reinforced concrete base 36 provided in the trench.

Three course of conventional apertured, 6 inch wide concrete blocks are laid on this base 36. Reinforcing rods 40 are placed in the apertures and then elongate channels 42 of 14 swg steel are laid on the top course of blocks 38. These channels are also prefabricated parts of the system and they are provided on their underside (i.e. the face of the channel base opposite to the channel opening) with projecting metal strips 44. These are welded on at the factory, as are bolts 46 projecting through into the channel.

The channels 42 are laid with the strips 44 projecting into the apertures in the blocks 38.

When the channels 42 have been laid and their position checked, the apertures in the blocks are filled with wet concrete. The projecting strips 44 constitute joggles which become embedded in this concrete so that the channels 42 are very firmly held to the foundation of the structure. The bolts 46 are positioned so as to align with bolt holes 8 in the panels.

After the channels 42 have been set in place, panels 2, 4 or 6 are fitted into the channels. The bolt holes 28 in their bottom edges fit over the bolts 46 which are positioned appropriately. These bolts hold the panels down into the channels 42. Adjacent panels 2, 4 or 6 are also bolted together and channels 48, prefabricated with bolt holes at appropriate positions, are fitted over the top of the panels and bolted to them as shown in Figs. 9 and 1 3. In this way a structure of wall panels secured together and secured at their base and top is rapidly built up from the prefabricated parts. Preferably all bolt holes are oval slots.

As indicated in the diagrammatic Fig. 13, the bottom and top channels 42, 48 do not run the full length of a wall. They are formed from convenient lengths of channel section which are chosen so that the break between two lengths does not coincide with the joint between two panels in a straight run. In this way the channels overlap the joints between panels and prevent hinging movement at these joints.

At each corner of the building there is an upright post 50, of angle section prefabricated with bolt holes, and the adjoining panels are both bolted to this as shown in tig. 5. Internal walls can also be made from the same set of standard panels and these are joined into the external walls as shown in Fig. 6. One web 52 of an upright upright angle section 50 is sandwiched between adjoining panels 54 of an exterior wall, and the adjoining panel 56 of an interior wall is bolted to the other web 58.

Another prefabricated component is the roof truss 60 illustrated in Fig. 10. Each of these trusses is made in two halves which are bolted together at the building site. Each half has a base 62, a main diagonal 64 and a central upright 66 provided with bolt holes for attaching to the central upright 66 the other half truss. Further diagonals and uprights lie within the outline of the truss. All these various parts of the truss are formed from pairs of angle sections welded together into a T section. This gives a strong truss of lighter construction than is normal for prefabricated trusses which frequently incorporate single lengths of heavier angle section or rolled steel section.On each main diagonal the truss carries five brackets 68 for supporting purl ins and at its outer ends the truss has welded to it horizontal plates 70 which are provided with holes at a spacing to align with bolt holes through the top channel 48 and the bolt holes 28 of panels beneath.

The panels 2, 4, 6 and trusses 60 are dimensioned so that an end wall can be built up from an exact number of the panels. In this embodiment the panels are 8 feet high and 4 feet wide and each truss has a span of 24 feet so that each end wall is formed from six panels. The side walls are also formed from an exact number of panels and as shown by the diagrammatic side elevation Fig. 13, the roof trusses are provided at the joints between alternate panels, giving an 8 foot spacing between the trusses, together with one four foot spacing because there is an odd number of side wall panels. The trusses 72 at each end of the building are constructed similarly to the trusses 60 except that expanded metal mesh is again sandwiched between the angle sections. These trusses 72 constitute gable ends.

Purlins 74 of rolled Z section are bolted onto the brackets 68. These purlins have a length sufficient to extend from one roof truss to the next. They are joined end to end by the brackets 68 which extend to either side of a roof truss and thereby have sufficient length to overlap with the ends of the purlins as shown in Fig. 11.

After these various prefabricated parts have been bolted together the water and sewerage pipes are installed and fixed in position by tying to the metal mesh 1 8 with pieces of wire. Electric cable ducts are fastened to the metal mesh in the same way. The metal mesh is then clad with concrete, preferably by the application of successive layers. No formwork is required for this; the mesh is itself capable of supporting wet concrete applied to it while that concrete begins to dry and then becomes capable of supporting a further layer. Expanded metal mesh has loops of metal projecting slightly at each side. At one side these are inclined upwards and at the other side they are inclined downwards. The concrete should first be applied on the side where the loops are inclined upwards. Concrete can then be applied successfully to the opposite side of the mesh.

The concrete which is applied can be ordinary concrete or aerated concrete and it can be applied manually with a trowel or can be applied by spraying from conventional concrete spraying equipment. Concrete is applied to the gable ends 72 as well as to the rectangular wall panels 2, 4, 6. The various prefabricated steel parts all become encased in and concealed by the applied concrete, up to the top of the walls. The steel work is preferably all degreased, and treated with a rust inhibitor as part of the factory fabricating operations. This has been found to give better concrete adhesion than with galvanised steel surfaces. Steelwork which remains exposed, such as door and window frames, the trusses 60 and the purlins 74, is degreased and painted at the factory.Once the concrete has been applied and allowed to set, the building interior and exterior can be finished and decorated in the same way as with a conventional concrete structure.

The roof can be of any conventional roof sheeting material such as galvanised iron or aluminium. The roof sheeting 76 is held to the purlins 74 by J-bolts 78 passing through large diamond-shaped washers in conventional manner, The embodiment described above has a number of important advantages.

Firstly, the building has reinforcing steel throughout its walls. Furthermore the reinforcing steel is connected together into a unitary assembly, and the channels 42, 48 are arranged to prevent one panel hinging relative to the next. These features together lead to a strong steelwork structure reinforcing the walls and giving them substantial strength to resist hurricane or earthquake. However, using this system cast reinforced concrete columns and beams are not required.

Secondly, because the steelwork structure is bolted to the bottom channel 42 which in its turn is secured to the reinforcing foundation by means of the projecting joggles 44, there is resistance to the entire building being lifted from its foundation by a hurricane.

The various prefabricated steel components can be mass produced in a factory which means that they can be made economically.

Because relatively light gauge steel is used throughout (14 swg is the thickest) and because of the sizes chosen for the prefabricated parts, all the prefabricated parts are light enough to be lifted by one man and the prefabricated parts can be assembled without any requirement for fixed scaffolding or a hoist. Portable scaffolding towers are sufficient. For example, a panel 2, as shown in Fig.

1 weighs only 46 Ibs.

The bolt holes provided during the factory prefabricating define the points of attachment making it possible for much of the assembly work to be carried out without specially trained labour.

The prefabricated parts are relatively small also, so that they can be carried by a moderate sized truck. The overall effect of economical prefabrication, unskilled labour and ease of transport is to give a very economical form of construction, especially suitable for houses.

It should be appreciated that although the above embodiment discloses preferred features, changes to it may be made within the scope of the invention which is by no means limited to the exact form of construction shown in the drawings.

Claims (24)

1. A system of prefabricated parts assemblable to form a building structure, to be coated with concrete after assembly, comprising panels with a metal frame infilled with a mesh or other perforate sheet capable of being coated with concrete elongate structural members attachable to the top and bottom regions of the panels, the said structural members and panels being provided with bolt holes or other means enabling them to be fastened together at positions defined by the said bolt holes or other fastening means.

2. A system according to claim 1 wherein the said mesh is expanded metal mesh.

3. A system according to claim 1 or claim 2 wherein each panel comprises a pair of frames each formed from metal angle section, with the said mesh or other perforate sheet sandwiched between the frames, each length of angle section having a web lying against the mesh or sheet and a web projecting therefrom.

4. A system according to any one of the preceding claims wherein said panels including panels with door openings formed therein, panels with window openings formed therein and panels with no such opening, all these panels being of uniform overall size.

5. A system according to any one of the preceding claims wherein the structural members attachable to the bottom regions of panels are metal channel sections to receive the bottoms of panels in the channels, and each having projections from the opposite face of the channel to be embedded in foundation concrete.

6. A system according to claim 5 wherein each channel has bolts welded to the base of the channel so as to project into the opening of the channel to pass through respective bolt holes provided on the panels.

7. A system according to any one of the preceding claims also including prefabricated metal roof trusses provided with bolt holes or other fastening means enabling them to be fastened to top regions of the panels and/or structural members attachable to top regions of the panels.

8. A system according to claim 7 wherein structural members attachable to top regions of the panels are metal channel sections to fit over the top of the panels, while the trusses are provided with plates to rest on the channel sections, these plates and channel sections being provided with bolt holes arranged to align with bolt holes in the tops of the panels.

9. A system according to claim 7 or claim 8 including gable ends which are prefabricated roof trusses, the frame of which is infilled with a mesh or perforate sheet capable of being coated with concrete.

10. A system according to any one of claims 7 to 9 wherein each roof truss carries brackets for the attachment of purlins these brackets projecting outwardly to either side of the truss.

11. A system of prefabricated parts substantially as herein described with reference to the accompanying drawings.

1 2. A method of constructing a building with the system of parts set forth in any one of the preceding claims, comprising bolting the said panels and structural members together, and coating the resulting structure with concrete.

13. A method of constructing a building with the system of parts set forth in claim 5 or any later claim appendant thereto, comprising the steps of providing foundation walls of concrete blocks with upwardly open apertures laying metal channel sections as set forth in claim 5 on the foundation walls with the said projections extending into the said apertures filling the apertures with concrete fitting said panels into the metal channel sections, and bolting them to the channel sections and to each other bolting said elongate structural members to the top regions of the panels, and coating the resulting structure with concrete.

14. A building panel comprising a metal frame infilled with a mesh or other perforate sheet, capable of being coated with concrete when upright, without formwork, the frame having parts projecting from each face of the mesh or other perforate sheet, which parts are provided with bolt holes or other fastening means enabling panels to be connected together.

15. A panel according to claim 14 wherein the said mesh is an expanded metal mesh.

16. A panel according to claim 14 or claim 15 having a pair of frames each formed from metal angle section, with the said mesh or sheet sandwiched between the frames, each length of angle section having a web lying against the mesh or sheet and a web projecting outwardly therefrom, and the bolt holes or other fastening means being provided in said outwardly projecting webs.

1 7. A building panel substantially as herein described with reference to any of Figs.

1 to 6 of the accompanying drawings.

18. A bottom member suitable to receive panels according to any one of claims 14 to 1 7 comprising a metal channel section to receive margins of the panels in the channel, and having projections from the opposite face of the base of the channel, to be embedded in foundation concrete.

19. A bottom member according to claim 1 8 having bolts welded to the base of the channel so as to project into the opening of the channel to pass through respective bolt holes provided on the panels.

20. A channel section substantially as herein described with reference to Figs. 7 to 9 of the accompanying drawings.

21. A prefabricated roof truss comprising a frame having horizontal, upright and diagonal members each formed from a respective pair of lengths of metal angle section, joined face to face to form a T section.

22. A roof truss according to claim 21 wherein the said frame is infilled with a mesh other perforate sheet capable of being coated with concrete when upright, without formwork, said mesh or sheet being sandwiched between the angle sections of each said pair.

23. A roof truss according to either claim 21 or claim 22 consisting of two halves connectable at a central upright.

24. A prefabricated roof truss substantially as herein described with reference to Figs. 10 to 12 of the accompanying drawings.