WO1997035079A1

WO1997035079A1 - Building structures

Info

Publication number: WO1997035079A1
Application number: PCT/GB1997/000743
Authority: WO
Inventors: John Joseph Freeman; Andrew William Leask
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-03-19
Filing date: 1997-03-18
Publication date: 1997-09-25
Anticipated expiration: 1998-09-19
Also published as: AU1936297A; GB9605763D0

Abstract

A building structure is formed from a plurality of prefabricated wall panels and a plurality of prefabricated floor slabs, a lower wall panel (10) being shown interconnected with an outer floor slab (12) and mounted on a support beam (14) of an arrangement forming part of the building foundation constructed on site. The wall panel (10) has a precast concrete component (16) and a layer of rigid insulation (20) bonded to one face thereof over a liquid impermeable flexible membrane (18) which extends to such a height as to define a suitable dampproof course. The panel (10) is also prefabricated with an interior wall sheet in the form of a cement particle board (22). The floor slab (12) has a concrete component (24), a layer of rigid insulation (20) bonded to one face thereof, and a liquid impermeable membrane (28), functioning as a dampproof course, bonded to the insulation (26). When mounted on the beam (14) on site, the panel (10) and the slab (12) can be interconnected and, by way of a further membrane (30) on the beam (14), a continuous waterproof membrane is formed. The building method eliminates many of the steps currently performed on site in adverse conditions and enables those steps to be carried out in a controlled factory environment.

Description

Building Structures

This invention relates to a building structure and more particularly to a method of forming a building structure and apparatus from which the building structure is formed.

According to one aspect of the present invention there is provided a method of forming a building structure, the method comprising prefabricating a plurality of wall assemblies by moulding one component of each from a structural material, securing an insulation material to one face of the structural component, and on at least some of the wall assemblies securing a liquid impermeable material sheet between the structural component and the insulation material over at least part of the wall assembly, prefabricating a plurality of floor assemblies by moulding one component of each from a structural material, securing an insulation material to one face of the structural component, and securing a liquid impermeable material sheet to the insulation material, preparing a foundation for the building structure on site, erecting the prefabricated wall and floor assemblies by supporting those wall assemblies having the material sheets and the floor assemblies on the foundation, and securing adjacent assemblies together with respective material sheets being liquid sealed together, whereby to form the building structure.

Preferably the prefabricating of each wall assembly mcludes the cladding of the insulation material on a face thereof remote from the structural component. The cladding may be a cement particle board.

Preferably also the material sheet on each of the respective wall assemblies is extended over a respective edge of the structural component. The insulation and material sheet on each of at least some of the floor assemblies may be extended beyond one or more edges of the structural component, and an additional insulation provided along the or each edge. On each assembly, the insulation may be secured to the structural component by bonding with a suitable adhesive. The securing of the liquid impermeable material sheet to the insulation on each floor assembly, and securing of the liquid impermeable sheet between the insulation and the structural component on said some wall assemblies, may be by bonding with a suitable adhesive.

Respective opposed edges of the insulation on each of the wall and floor assemblies may be tongue and grooved whereby adjacent assemblies can be interconnected by locating the tongue of one of the assembUes into the groove of the adjacent assembly.

Advantageously the external face of the structural component of at least certain of the wall assembUes is provided with a decorative finish during prefabrication.

Beams are preferably supported by the foundation and provide support surfaces for the floor and wall assemblies, and a liquid impermeable material sheet is located on each of the support surfaces whereby to cooperate with the material sheets of the floor and wall assemblies in a sealed relation.

The foundation may be prepared by inserting piles on site, capping the piles and mounting support beams on the pile caps.

At least some adjacent assemblies may be secured together by bolting through said one component of one assembly into said one component of the adjacent assembly. At least some adjacent wall assemblies may be connected by means of a plate locating in recesses in respective edges of aligned said one components of the assemblies and being bonded into the recesses. At least some adjacent floor assemblies may be connected by dowels locating in aligned recesses in respective edges of adjacent said one components of the assemblies and being bonded into the recesses. During prefabrication of at least some of the wall assemblies, lifting devices may be incorporated whereby a roof structure can be erected on the building structure by attaching plates to the lifting devices and mounting roof trusses on the plates.

The invention also provides a building structure formed by the method according to any of the ten preceding paragraphs.

According to another aspect of the invention there is provided apparatus for forming a building structure, the arrangement comprising a plurality of prefabricated wall assemblies, each of which comprises a component moulded from a structural material, an insulation material secured to one face of the structural component, and a Uquid impermeable material sheet secured on at least some of the wall assemblies between the structural component and the insulation material over at least part of the respective wall assembly, a plurahty of prefabricated floor assemblies, each of which comprises a component moulded from a structural material, an insulation material secured to one face of the structural component, and a liquid impermeable material sheet secured to the insulation material, and means for securing prefabricated waU and floor assemblies together on site with adjacent material sheets Uquid sealed together, whereby to erect the building structure on an on-site foundation.

Preferably said one component of each assembly is moulded from a cementitious material, for example concrete.

Preferably also the insulation material on each wall assembly is cladded on a face thereof remote from the structural component, for example with a cement particle board.

Opposed edges of the insulation material on each of the wall and floor assemblies may have a tongue and a groove respectively, whereby the insulation material of adjacent assemblies, and thus the adjacent assemblies themselves, can be accurately secured together. An external face of the structural component of each of at least certain of the wall assemblies can be provided with a decorative finish, such as a moulded relief pattern. The material of the structural component of each of at least some of the assemblies may be coloured.

Preferably each of the liquid impermeable material sheets has the form of a flexible membrane, for example of plastics, to define a dampproof course.

The invention also provides a building structure formed of apparatus according to any of the six preceding paragraphs.

An embodiment of the present invention will now be described by way of example only, with reference to the accompanying drawings, in which:-

Fig. 1 is a part-sectional elevation through part of an erected building structure according to the invention;

Fig. 2 is a part-sectional elevation through an upper part of the building structure with an associated roof structure;

Fig. 3 is a part-sectional elevation through a joint between adjacent waU assemblies or panels;

Fig. 4 is a part-sectional elevation through a joint between adjacent floor assemblies or slabs; and

Fig. 5 is a part-sectional elevation through part of a foundation.

Referring to the drawings, a building structure is formed from a plurality of prefabricated wall assemblies or panels and a plurahty of prefabricated floor assemblies or slabs. Part of one design of a lower wall panel 10 is shown in Fig. 1 together with one design of an outer floor slab 12. The panel 10 and slab 12 are shown interconnected and mounted on one support beam 14 of an arrangement of support beams forming part of the building foundation as hereinafter described.

The wall panel 10 is formed of a precast concrete component 16 of substantially rectangular configuration, to one face of which, at a lower section thereof, is bonded a membrane 18 in the form of a liquid impermeable flexible plastics sheet defining a suitable dampproof course. The membrane 18 is bonded to said one face to such a height as to be at least 150 mm above external ground level. The required height above ground level may vary depending on which country the building structure is to be formed. The membrane 18 extends beyond the lower end of said one face to locate on the lower edge of the component 16. The concrete component 16 is cast in a mould designed to ensure that the thickness of the concrete is guaranteed within acceptable tolerances. Where the panel 10 forms an external waU, coloured concrete can be used and can be patterned, for example by including a mat in the mould. The external wall surface appearance can therefore be selected by the intended occupier of the building and it is also envisaged that a logo of the occupier could be cast in the external wall surface if desired. It will be appreciated however that it is not necessary to have any pattern on the extemal walls, and a smooth surface and natural colour for finishing with appropriate paint can be provided. The wall panels when cast are coated with a clear seal, allowing for easy cleaning of the concrete.

A layer of rigid insulation 20 is bonded to said one face of the component 16 over the membrane 18 and the open face of the insulation 20 is finished with an interior wall sheet bonded thereto, for example a sheet of cement particle board 22. The latter does not degrade if it becomes wet and will dry out in around two days. The interior wall sheet may be such as to protect the insulation from fire, although this may require a mechanical fixing of the interior wall sheet to the concrete component 16 in addition to the bonding of the sheet to the insulation 20. In the lower wall panel 10, the insulation 20 and board 22 terminates short of a lower edge of the component 16 and membrane 18, for connection to the floor slab 12 as hereinafter described.

The insulation 20 can be varied in thickness to suit cUmatic conditions of the site where the building is to be constructed. As shown in Fig. 3, opposite edges of the insulation 20 are formed with respective tongues 20a and grooves 20b whereby to ensure the insulation of adjacent panels can accurately interconnect and thereby accurately connect adjacent panels together, with accurate sealing by gluing, for example using an epoxy concrete glue. The insulation 20 is machined to very high tolerances whereby, by also casting the concrete component 16 within acceptable tolerances, as weU as making the board 22 to acceptable tolerances, both acceptable external and internal joints are created.

It is to be appreciated that other wall panels may be formed with the insulation and board over the whole surface thereof, and that, where necessary, the wall panels will be prefabricated with windows etc., the membrane 18 being appropriately positioned to seal on to the window frames and the like.

The floor slab 12 has a concrete component 24 of substantially rectangular configuration and a layer of rigid insulation 26 bonded to one face thereof. A membrane 28 in the form of a liquid impermeable plastics sheet functioning as a dampproof course, is bonded to the open face of the insulation 26. The concrete component 24 terminates short of an outer edge of the panel 12 to enable a further layer of insulation 32 to be positioned outwardly of the concrete for a purpose hereinafter described.

Each concrete component 24 is also cast in a specially designed mould to ensure that the thickness of the concrete is guaranteed within acceptable tolerances. The surface of the component 20 to form the floor can be controlled, for example by casting the component 28 upside down in a high quality mould lined with a suitable material to ensure a high quality finish. A final top dressing can be applied to guarantee the surface quality of the floor surface before the application of a clear sealant which provides a hard wearing coating preventing staining of the concrete. Coloured concrete can be used. High quality floor slabs 12 can therefore be prefabricated with a finished floor surface before being delivered to site.

The insulation 26 again has opposite edges with respective tongues 26a and grooves 26b whereby to ensure accurate interconnection of the insulation of adjacent floor slabs and therefore of the adjacent floor slabs themselves (Fig. 4). The insulation 24 is machined to very high tolerances and as the concrete is cast with acceptable tolerances, acceptable joints between floor slabs are created. The insulation can be varied in thickness to suit climatic conditions of the site, and the load bearing capacity of the insulation is chosen to suit the imposed loads in order to ensure minimal settlement. There are materials available with different load bearing capacities and, for example, it may be necessary to have a higher load insulation where a floor slab is supported, than in other areas where the insulation is purely used for insulation purposes.

The wall panels and floor slabs are prefabricated in a factory and then delivered to the site for the building structure. At least those panels which will form the upper wall panels of the structure, one of such panels 34 being shown in Fig. 2, each have incorporated, on a top edge of the concrete component 16, a lifting device 36 which enables a timber plate 38 to be attached thereto by means of a bolt 40. The plates 38 can be used to enable attachment thereto of roof trusses 42 of a roof structure 44.

As an alternative, or in addition, to gluing, at least some of the wall panels may be formed in respective edges of the concrete component 16 with recesses 46 (see Fig. 3), the recesses 46 of adjacent wall panels being ahgned when the panels are positioned in an abutting relation. An mterconnecting plate 48 has one end bonded in one of the adjacent recesses 46, whereby to locate into the ahgned recess 46 of the adjacent wall panel when the latter is moved into the abutting relation, and be bonded thereto thereby interconnecting the panels. A sealing gasket 50 is located between the adjacent edges of the wall panels. In a similar way, adjacent floor slabs are interconnected by means of a dowel 52 (see Fig. 4) bonded into aligned recesses 54 in adjacent edges of the concrete component 24 of abutting floor slabs.

It is also anticipated that, in the building structure to be erected, the path for required services can taken through the insulation 20 of the wall panels and the insulation 26 of the floor slabs, and provision for this, and for necessary sealing, can be made when the wall panels and floor slabs are prefabricated in the factory. For example, grooves can be formed in the insulation of wall panels before the interior wall sheet is bonded to the insulation. Alternatively, surface or skirting trunking can be used.

On site, a foundation for the building structure is created by the use of piles 56 (see Fig. 5) each of which is capped and labelled, providing a cap 58, the support beams 14 being mounted on the caps 58. The use of up-to-date piling techniques enables speeding up of the time on site for creating the required foundation. If the ground does not require the use of pUes, the support beams 14 may be instaUed on paving slabs which replace the pUe caps at the junctions of the floor slabs, the beams then being levelled and concrete being poured between the ground and the beams to support the latter over their length. If appropriate, the paving slabs may be cast on site by traditional methods with levelling compound being used to ensure the required tolerances are met over the whole site. It is necessary to ensure that all the floor slab edge supports are level across the site and that the supports are square to the perimeter which is set square. It may be appropriate to support the floor slabs along all four edges.

The prefabricated wall panels and floor slabs are taken on site with the lower wall panels and the floor slabs being suitably mounted on the beams 14. As shown in Fig. 1, a lower wall panel 10 can locate relative to an outer floor slab 12 with the latter positioned below the insulation 20 and plasterboard 22 of the panel 10. The latter is secured to the floor slab 12 by means of an anchor bolt 60 which is introduced through the concrete component 16 of the panel 10 through the insulation 32 of the floor slab 12 and into the concrete component 24 of the latter. The head of the anchor bolt 60 locates in a rebate in the component 16 which is subsequently infilled. The beam 14 supporting the wall panel 10 and the floor slab 12 has a membrane 30 in the form of a liquid impermeable flexible plastics sheet bonded to its upper surface by suitable adhesive, the membrane 30 extending below both the wall membrane 18 extending across the lower edge of the concrete component 16 of the wall panel 10, and the membrane 28 of the floor slab 12. The membranes 18, 28 and 30 are bonded together to form the required seal. Similarly, where adjacent floor slabs 12 are supported on a beam 14 (Fig. 4), the latter has a membrane 31 bonded by suitable adhesive to its support surface whereby the membrane 68 locates below each of the respective membranes 28 and can be bonded to the latter to form a sealed joint.

Once the building structure is completed by interconnecting appropriate wall panels and floor slabs in accordance with the connecting methods herein¬ before described, the building can be completed by erection of the roof struc¬ ture 44 incorporating a suspended ceiling 62, a ventilated soffit 64, and other conventional roof structure components and insulation. By attaching suitable plates to the concrete components of wall panels through the insulation using a thermal break material, it is envisaged that lattice beams can be fixed to the wall panels at appropriate positions to function as supports for the construction of a roof. Multiple storeys can be constructed within the bmlding structure by utilising similar wall panels and floor slabs or alternatively other panel types such as timber framed panels. Intervening floors may be supported on timbers bolted to the concrete components of external waUs through the insulation using a thermal break fixing method. The thickness of the concrete component on external wall panels can be varied to suit the loads the concrete is expected to carry from internal floors or roofs. It is also possible to create load bearing columns by bonding and pinning another pre-cast concrete component to that of a prefabricated wall panel. The column can be formed externally of the wall panel and, for example, have the same pattern as the external wall surface of the panel, or can be formed internally and be embraced by the insulation during fabrication.

When wall panels are connected together and floor slabs are connected together, and also when wall panels are connected to floor slabs, it is important to ensure a continuous waterproof membrane by providing a suitable water¬ tight seal between adjacent membranes. There is thus provided a building system which eliminates many of the steps currently performed on site in adverse conditions and enables those steps to be carried out in a controlled factory environment. The amount of labour and management supervision required on site is substantiaUy reduced and a high quality, close tolerance building can be created in substantially less time than is normal. The structure and the method of instaUation enables a building to be supplied and installed at known costs whatever the ground conditions found on site may be. The building system is a highly engineered product, working on very close tolerances on the different materials used in its manufacture and installation, in order to enable the requirements of the appropriate authorities to be satisfied in terms of performance with regard to insulation, water penetration etc. Elements can be varied to suit the local conditions found or required in various countries. There is effectively no wet work required on site and correspondingly no curing time as panels and slabs are mechanicaUy fitted together. The use of coloured concrete, sculptured outer wall surfaces and decoratively finished floors proves acceptable.

Claims

Claims:-

1. A method of forming a building structure, the method comprising prefabricating a plurality of wall assemblies by moulding one component of each from a structural material, securing an insulation material to one face of the structural component, and on at least some of the waU assembUes securing a liquid impermeable material sheet between the structural component and the insulation material over at least part of the wall assembly, prefabricating a plurality of floor assemblies by moulding one component of each from a structural material, securing an insulation material to one face of the structural component, and securing a Uquid impermeable material sheet to the insulation material, preparing a foundation for the building structure on site, erecting the prefabricated waU and floor assemblies by supporting those waU assembUes having the material sheets and the floor assemblies on the foundation, and securing adjacent assembUes together with respective material sheets being liquid sealed together, whereby to form the building structure.

2. A method according to Claim 1, wherein the prefabricating of each waU assembly includes the cladding of the insulation material on a face thereof remote from the structural component.

3. A method according to Claim 2, wherein the insulation material is cladded with a cement particle board.

4. A method according to any of Claims 1 to 3, wherein the material sheet on each of the respective wall assemblies is extended over a respective edge of the structural component.

5. A method according to any of the preceding Claims, wherein the insulation and material sheet on each of at least some of the floor assemblies is extended beyond one or more edges of the structural component, and an additional insulation is provided along the or each edge.

6. A method according to any of the preceding Claims, wherein, on each assembly, the insulation is secured to the structural component by bonding with a suitable adhesive.

7. A method according to any of the preceding Claims, wherein securing of the liquid impermeable material sheet to the insulation on each floor assembly, and securing of the liquid impermeable sheet between the insulation and the structural component on said some wall assemblies, is by bonding with a suitable adhesive.

8. A method according to any of the preceding Claims, wherein respective opposed edges of the insulation on each of the wall and floor assembUes are tongue and grooved whereby adjacent assemblies can be interconnected by locating the tongue of one of the assemblies into the groove of the adjacent assembly.

9. A method according to any of the preceding Claims, wherem the extemal face of the structural component of at least certain of the waU assemblies is provided with a decorative finish during prefabrication.

10. A method according to any of the preceding Claims, wherein beams are supported by the foundation and provide support surfaces for the floor and wall assemblies, and a liquid impermeable material sheet is located on each of the support surfaces whereby to cooperate with the material sheets of the floor and wall assemblies in a sealed relation.

11. A method according to Claim 10, wherein the foundation is prepared by inserting piles on site, capping the piles and mounting the support beams on the pile caps.

12. A method according to any of the preceding Claims, wherein at least some adjacent assemblies are secured together by bolting through the structural component of one assembly into the structural component of the adjacent assembly.

13. A method according to any of the preceding Claims, wherein adjacent wall assemblies and adjacent floor assemblies are connected by gluing.

14. A method according to any of the Claims 1 to 12, wherein at least some adjacent wall assemblies are connected by means of a plate locating in recesses in respective edges of aligned structural components of the assemblies, the plate being bonded into the recesses.

15. A method according to any of the Claims 1 to 12 and Claim 14, wherein at least some adjacent floor assemblies are connected by dowels locating in aligned recesses in respective edges of adjacent structural components of the assemblies, the dowels being bonded into the recesses.

16. A method according to any of the preceding Claims, wherem, during prefabrication of at least certain of the wall assembUes, lifting devices are incorporated and on site a roof structure is erected on the building structure by attaching plates to the lifting devices and mounting roof trusses on the plates.

17. Apparatus for forming a building structure, the arrangement comprising a plurahty of prefabricated wall assemblies, each of which comprises a component moulded from a structural material, an insulation material secured to one face of the structural component, and a liquid impermeable material sheet secured on at least some of the wall assemblies between the structural component and the insulation material over at least part of the respective wall assembly, a plurality of prefabricated floor assemblies, each of which comprises a component moulded from a structural material, an insulation material secured to one face of the structural component, and a liquid impermeable material sheet secured to the insulation material, and means for securing prefabricated wall and floor assemblies together on site with adjacent material sheets Uquid sealed together, whereby to erect the building structure on an on- site foundation.

18. Apparatus according to Claim 17, wherein each structural component is moulded from a cementitious material.

19. Apparatus according to Claim 18, wherein the cementitious material is concrete.

20. Apparatus according to any of Claims 17 to 19, wherein the insulation material on each waU assembly is cladded on a face thereof remote from the structural component.

21. Apparatus according to Claim 20, wherein the insulation material is cladded with a cement particle board.

22. Apparatus according to any of Claims 17 to 21, wherem opposed edges of the insulation material on each of the wall and floor assembUes have a tongue and a groove respectively, whereby the insulation material of adjacent assemblies, and thus the adjacent assemblies themselves, can be accurately secured together.

23. Apparatus according to any of Claims 17 to 22, wherein an external face of the structural component of each of at least certam of the wall assemblies is provided with a decorative finish.

24. Apparatus according to Claim 23, wherein the decorative finish has the form of a moulded relief pattern.

25. Apparatus according to any of Claims 17 to 24, wherem the material of the structural component of each of at least some of the assemblies is coloured.

26. Apparatus according to any of Claims 17 to 25, wherein each of the liquid impermeable material sheets has the form of a flexible membrane to define a dampproof course.

27. Apparatus according to Claim 26, wherein the material sheet is formed of a plastics material.

28. A building structure formed by the method accordmg to any of Claims 1 to 16.

29. A building structure formed by the apparatus according to any of Claims 17 to 27.

30. A method of forming a building structure substantiaUy as hereinbefore described with reference to the accompanying drawings.

31. Apparatus for formmg a building structure substantiaUy as hereinbefore described with reference to the accompanying drawings.

32. A building structure substantiaUy as hereinbefore described with reference to the accompanying drawings.

33. Any novel subject matter or combination including novel subject matter disclosed, whether or not within the scope of or relating to the same invention as any of the preceding claims.