WO2015128786A1

WO2015128786A1 - A cast structural element

Info

Publication number: WO2015128786A1
Application number: PCT/IB2015/051324
Authority: WO
Inventors: Heinrich Alfred SCHOLTEN
Original assignee: WOLDT, Roman
Priority date: 2014-02-25
Filing date: 2015-02-21
Publication date: 2015-09-03

Abstract

Disclosed is a cast structural element (1) which comprises a matrix of cast structural material (2) at least partly containing a sheet of insulation material (3), preferably with the cast structural material (2) comprising a cementitious material and with the insulation material (3) comprising magnesium oxide.

Description

A CAST STRUCTURAL ELEMENT

FIELD OF THE INVENTION

This invention relates to a cast structural element used in the construction of buildings, walls and the like.

BACKGROUND TO THE INVENTION

Buildings and walls are constructed using various techniques and structural elements. These include using building blocks such as bricks which are packed in off-set layers with mortar between adjoining bricks and layers to secure the bricks to each other.

Walls may also be created by placing panels between upright supports. The panels may comprise precast concrete or cement, or fibrous or other compressed material in so-called dry-walling.

Another alternative is for a wall to be to cast-in-place, in which case formwork is constructed to define a volume that the wall will occupy once cast. The formwork is filled with wet concrete or cement to fill the cavities and cure over time. Once cured sufficiently the formwork is removed to allow final curing of the wall.

Similarly, buildings also require foundations, floors and ceilings. In double storey buildings it is common for the ceiling of one level to function as the floor for the next level. Such a floor or ceiling is commonly constructed by placing precast concrete slabs on support beams, or it is cast in situ.

In many constructions walls and floors are finished with tiles, which are painstakingly secured to walls and/or floors by means of tile cement. This is a laborious task which, if done to good quality, has to be performed by specialist tiling artisans. A tiling artisan is generally substantially more expensive than a bricklayer, but a bricklayer typically cannot or at least should not if quality is a consideration, be used for tiling,. A consideration with most buildings is energy efficiency, and with increasing electricity generation costs and electricity supply constraints an ever increasing focus is placed on the energy efficiency of newly constructed buildings. This is not only the case for buildings in traditionally 'cold' areas such as countries in the northern hemisphere, but increasingly also in countries with more moderate climates. For example, even in Southern African countries with very moderate climates it is becoming compulsory to design residential homes to meet minimum energy efficiency standards.

These considerations require floors, walls, ceilings and windows to prevent to a predetermined degree the loss of energy from such a building through radiation.

To achieve these energy efficiency standards, especially walls, ceilings and windows have to be thermally insulated in some manner or form. In the case of windows this may take the form of double glazing windows or fixing emission restrictive shields on the glass panes.

In the case of walls it is sometimes necessary to build a double wall with a layer of insulation in-between. Presently one of walls is first built, after which insulation board is attached to the wall. The board is pierced in several places to fit over metal ties, anchors, pipe work and electrical conduits. This is a messy job and often insulation boards break off or are blown away by wind gusts. After fitting the boards the builder has to erect the second wall, to locate the insulation board between the two walls. This is done without being able to see the first wall, because it is then hidden from sight by the insulation board. This makes height alignment of the second wall with the first wall difficult.

Alternatively, insulation board is glued to the exterior of a single or double wall and rendered to harden and waterproof the wall. This leaves the insulation board vulnerable to environmental damage and aging.

These processes are expensive and time consuming.

In the case of ceilings it is very often necessary to place thermal insulation on top of the ceiling. This may take the form of a layer of insulation wool or shredded fibrous material. In both cases this provides acceptable insulation properties but unfortunately also forms excellent nesting material for insets and rodents. Existing building materials and techniques do not provide an easy solution to the abovementioned problems. OBJECT OF THE INVENTION

It is an object of the invention to provide a cast structural element which at least partly overcomes the abovementioned problems. SUMMARY OF THE INVENTION

In accordance with the invention there is provided a cast structural element which comprises a matrix of cast structural material at least partly containing a sheet of insulation material. There is provided for the cast structural material to comprise a cementitious material, preferably concrete or cement, and for the insulation material to preferably comprise magnesium oxide.

There is further provided for the structural element to comprise a panel in abutment with an insulation material panel, preferably cast into abutment with it, alternatively for the structural element to comprise two panels between which an insulation material panel is located, preferably cast into abutment with it; and further preferably for the or each structural material panel to have the same length and height as the insulation material panel, and more preferably for the or each structural material panel to also have the same thickness as the insulation material panel.

According to an alternative asepct of the invention there is still further provided for the or both insulation material panels to extend from both ends of the cast structural element by a predetermined length equal to half of a predetermined mortar gap between adjoining cast structural element in a wall or floor to be formed by a plurality of the cast structural elements, as the case may be.

There is still further provided for the or both insulation material panels to extend from one end of the cast structural element by a predetermined length equal to that of a predetermined mortar gap between adjoining cast structural element in a wall or floor to be formed by a plurality of the cast structural elements, as the case may be. According to a still feature of the invention there is provided for the structural element to comprise two outer structural material panels within which two insulation material panels are located spaced apart by a third centrally located structural material panel.

There is also provided for at least one reinforcing rod to be transversely embedded in the structural element to extend through the sheet of insulation material and at least partly into the cast structural material, and preferably into both structural material panels where the structural element comprises an insulation panel sandwiched between two cast structural material panels, and further preferably into both cast structural material panels adjacent each insulation panel where the structural element comprises two outer cast structural material panels within which two insulation material panels are located spaced apart by a centrally located cast structural material panel. There is provided for the cast structural element to comprise a building block, preferably having ends with complimentary shaped and sized engaging formations.

There is further provided for the complimentary engaging formations, in a building block that comprises two structural material panels between which an insulation material panel is located, to be formed by the one structural material panel being aligned fully with the insulation panel and the other structural material panel being offset in the length of the building block to extend at one end beyond the end of the aligned structural material panel and insulation panel, and at the other end of the building block for the end of the aligned structural material panel and insulation panel to extend beyond the end of the offset structural material panel, and preferably for the length by which the structural material panel is offset from the aligned structural material panel and insulation panel to correspond to the combined thickness of the aligned structural material panel and insulation panel.

There is further provided for the complimentary engaging formations, in a building block that comprises two outer structural material panels within which two insulation material panels are located spaced apart by a central structural material panel, to be formed by the building block having a stepped end at both ends along the longitudinal centre line of the third centrally located structural material panel, to form a building block with steps of equal length at both ends. There is also provided for each structural material panel and each insulation panel to have a thickness of about 40mm.

According to a still further aspect of the invention there is provided for the cast structural element to be provided with a finished surface on at least one of its sides, and further for the finished surface to comprise a tile secured to such side.

In accordance with a further aspect of the invention there is provided a planar arrangement of structural elements according to the invention contiguously interlocked to form a single plane, and preferably for the planar arrangement to comprise a floor, wall or ceiling.

There is still further provided for a wall, floor or ceiling having a finished surface, preferably a tiled wall, floor or ceiling, comprising a plurality of structural elements with a finished surface contiguously arranged end to end with their finished surfaces all on one side.

There is provided for an intersecting arrangement of three cast structural elements according to the invention comprising two structural material panels between which an insulation material panel is located, with their similar ends in abutment to form a single plane with a stepped channel at their abutting ends, with the complimentary end of a third similar cast structural element located in the channel in a substantially perpendicular relationship to the plane.

In accordance with a further aspect of the invention there is provided a method for making a cast structural element which includes locating a sheet of insulation material in a mould, casting a structural material into the mould, and allowing the product to cure for a predetermined period until stable.

These and other features of the invention are described in more detail below. BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention are described by way of example only and with reference to the accompanying photographs in which: Figure 1 is a top perspective view of a representation of a structural element according to a first embodiment of the invention; Figure 2 shows an end-to-end arrangement between two structural elements of the embodiment shown in Figure 1 , and detail of the joint between them;

Figure 3 shows an intersecting joint, and detail thereof, of three structural elements according to the first embodiment of the invention shown in Figure 1 ;

Figure 4 is a top perspective view of a representation of a structural element according to a second embodiment of the invention;

Figure 5 is a perspective view of an end-to-end arrangement of two structural elements according to the second embodiment shown in Figure 4;

Figure 6 shows a top perspective view of a representation of an insulating sheet prior to being placed in a mould for structural material to be cast around it, with a plurality of transverse reinforcing rods through it; and

Figure 7 is a top perspective view of a representation of a structural element according to a third embodiment of the invention. DETAILED DESCRIPTION OF THE INVENTION

A first embodiment of a cast structural element (1 ) according to the invention is shown in Figures 1 to 3. This cast structural element (1 ) comprises a matrix of cast structural material (2) at least partly containing a sheet of insulation material (3).

In this embodiment the structural material (2) comprises concrete and the insulating material (3) comprises magnesium oxide.

The insulating material (3) is provided in the form of a magnesium oxide panel (5) which is partially embedded within the concrete (4), having concrete (4) on both sides thereof to effectively sandwich it.

The concrete (4) is cast around the magnesium oxide panel (5) to bind with it and cure to form the structural element (1 ). In this embodiment the structural element (1 ) thus comprises a cast building block (6) which can be used to construct a wall, floor panel or ceiling panel with integrated thermal insulation.

As shown in Figure 1 the building block (6) has offset ends (7A, 7B), with the insulating panel (3) being fully aligned with a panel of concrete (4A) on one end (7A) but with the second panel of concrete (4B) being offset by a predetermined length at the same end (7A) of the aligned insulating panel and first concrete panel. This creates a step (7) in the ends of the building block (6).

At the opposite end (7B) of the building block the insulating panel extends beyond both ends of the two panels (4A, 4B) between which is located. This provides a stepped end (7B) to the block that is different to the first described stepped end (7A).

These step ends (7A, 7B) in the building block (6) allow for two blocks (6A, 6B) to be located end-to-end with the stepped ends (7A, 7B) dovetailing onto each other, whilst leaving a mortar gap (8A, 8B) of predetermined width between the aligned concrete panels of the two block (6A, 6B). This is shown in the detail of Figure.

It is also possible to create an intersecting junction (10) using the building blocks (1 1 ) according to this first embodiment of the invention, as shown in Figure 3. In this instance two blocks (1 1 A, 1 1 B) in a row are aligned end-to-end such that the single extending concrete panel (12) of one block (1 1 A) is aligned and in abutment with the concrete panel (13) of a second block (1 1 B). This leaves a mortar gap (15) between ends of these blocks (1 1 A, 1 1 B), and a larger gap (16) on the opposite side of the two end-to-end blocks (1 1 A, 1 1 B). Into this larger gap (16) the end (17) of a third block (1 1 C) may be located to complete the intersecting junction (10). The location of the third block (1 1 C) into the larger gap (16) also provides spaces (17A, 17B) for mortar to be filled into the intersection (10).

This first embodiment of the cast structural element (1 ) according to the invention includes two concrete panels (4A, 4B) sandwiching a single insulating panel of magnesium oxide (5). This provides a building block (6) which may be used for a single wall construction, floor panel or ceiling panel.

A second embodiment of a cast structural element (20) according to the invention is shown in Figures 4 and 5. This cast structural element (20) comprises a sandwich of two spaced apart insulating panels (21 A, 21 B) within a matrix of three spaced apart concrete panels (22A, 22B, 22C). It includes two outer concrete panels (22A, 22C) within which two insulation material panels (21 A, 21 B) are located spaced apart by a central concrete panel (22B).

This cast structural element (20) also forms a building block (23). It also includes stepped ends (24A, 24B) which allows for such blocks (23) to be located end-to-end (25) for structural integrity purposes, as shown in Figure 5. As mentioned above, the outer panels (22A, 22C) and the central panel (22B) of this cast structural element (20) are concrete panels. The insulating panels (21 A, 21 B) are magnesium oxide panels.

The two insulating panels (21 A, 21 B) are located on opposite sides of the central concrete panel (22B), each having a concrete panel (22A, 22C) on its outside. The centrally located concrete panel (22B) is stepped at its ends, with it being aligned at one end (24A) with the one insulating panel (21 B) and stepped out beyond the end of the other insulating panel (21 A), and at the other end (24B) being set back from both insulating panels (21 A, 21 B).

As is shown in Figure 5 two blocks (23) of this second embodiment (20) may be aligned end to end to align and to provide mortar gaps (25-27) of predetermined thickness. The building blocks (6, 23) are cast with each of the panels that comprise it having a typical thickness of about 40mm. This provides the first embodiment (6) with a thickness of about 120mm and the second embodiment (23) with a thickness of about 200mm, which is similar to standard single and double wall thicknesses. As will be apparent, the cast structural elements (1 , 20) don't only function as building blocks for walls. These may also be used for floors or ceilings. The structural elements may be reinforced to allow it to bear weight, which is a requisite in some applications.

The integrated insulating panels within the cast structural elements have significant benefits. They provide predictable and consistent insulating properties to structures. The speed at which a building may be constructed using these structural elements is also increased since the phased construction of a double wall with insulating cladding in its centre is eliminated. The builder simply builds as if the building blocks were normal building blocks or bricks. Of course, if desired the structural elements may be produced with flat ends, i.e. having no offset ends. This may be useful for builders that wish to lay building blocks in a completely conventional manner, which does not use the offset ends or with mortar gaps. The size of the structural elements may also be modified to suit specific purposes. Indeed it is envisaged that some builders may be most comfortable with structural elements that have the same dimensions as conventional sized bricks, and cast structural elements according to the invention could also be provided in such dimensions. The structural elements (1 , 20) are cast by creating a mould and locating one or more insulating panels within it, depending on the embodiment (1 , 20) of the structural element to be created. The insulating panel has flat edges allowing it to stand on its edge in the mould.

As shown in Figure 6 the insulating panel (30) may be provided with reinforcing rods (31 ) that extend through it. The length by which the ends of each rod (31 ) extend on the both sides of the insulating panel (30) is less than the thickness of the to-be cast concrete panel. This ensures that the rods (31 ) are completely contained within the final cast structural element on either side.

Concrete is then cast into the mould (not shown) on both sides of the insulating panel (30). To ensure the concrete does not push the insulating panel (30) to one side of the mould during casting and the insulating panel is thus located centrally in the mould, the panel (30) may be braced within the mould, for example by means of clamps to its upper edge. These can be removed once the mould has been filled, to allow for full contact between the concrete on the surfaces of the insulating panel (30).

In this configuration the edges of the insulating panel (30) are in contact with the bottom and ends of the mould, and the top edge of the insulating panel (30) is level with the top of the mould. This means the two concrete panels on opposite sides of the insulating panel do not contact each other, making for true sandwich configuration.

It is possible to also suspend the insulating panel within the mould prior to casting, for example by using thin wire strands extending between the insulating panel and the edges of the mould. The concrete is then cast around the insulating panel to complete encapsulate.

It is also possible to locate the insulating panel only with one edge, for example the bottom edge, against the mould surface. In such instance the ends and top edge of the insulating panel would not extend to the mould ends and top, allowing concrete to be cast around those edges of the insulating panel.

A third embodiment (40) of a cast structural element according to the invention is shown in Figure 7. In this embodiment (40) an insulation panel (41 ) of magnesium oxide is located between two cast concrete panels (42A, 42B). To the outer surface of each concrete panel (42A, 42B) there is affixed a ceramic tile (43A, 43B), having the same length and width as the two panels (42A, 42B). This allows the building block (40) so-formed to be used as block in wall that is intended to have a tiled surface on both sides, for example for an inner wall in a building. The block (40) is thus provided with a finished surface (in the form of the ceramic tile).

It is also possible to affix a ceramic tile to only one of the concrete panels (42A, 42B) of the block, as would be required where on side of the wall to be formed by it would not be tiled (for example forming an outer wall of a building, where the outer wall may be plastered and painted).

It will be appreciated that surface finishes other than ceramic tiles may be used, for example porcelain tiles, or other types of decorative surface finishes.

It will be appreciated that the embodiments described above are given by way of example only, and are not intended to limit the scope of the invention. It is possible to alter aspects of the embodiments without departing from the essence of the invention.

It is for example possible to use insulating material other than a magnesium oxide panel. It is also possible to use a structural material other than concrete, for example other cementitious materials.

It is also possible to form the cast structural element with engaging formations other than one the ends thereof. It is for example possible to form complimentary engaging formations along the top and bottom edges thereof. It is also possible to form engaging formations other than steps, for example by forming a tongue and groove formation at the ends or along the top and bottom edges.

It is also possible to cast the structural element with services apertures there through, for example standard apertures for water pipes and electrical conduits.

Claims

1 . A cast structural element which comprises a matrix of cast structural material at least partly containing a sheet of insulation material.

2. A cast structural element as claimed in claim 1 in which the cast structural material comprises a cementitious material.

3. A cast structural element as claimed in claim 2 in which the insulation material comprises magnesium oxide.

4. A cast structural element as claimed in claim 2 or 3 in which the cementitious material comprises concrete or cement.

5. A cast structural element as claimed in any one of claims 1 to 4 in which the structural material comprises a panel in abutment with an insulation material panel.

6. A cast structural element as claimed in claim 5 which includes two structural material panels between which an insulation material panel is located.

7. A cast structural element as claimed in claim 5 or 6 in which the structural material panel is cast into abutment with the, or both, insulation material panels, as the case may be.

8. A cast structural element as claimed in any one of claims 1 to 4 in which the structural element comprises two outer structural material panels within which two insulation material panels are located spaced apart by a third centrally located structural material panel.

9. A cast structural element as claimed in claim 8 in which the structural material panel is cast into abutment with both insulation material panels.

10. A cast structural element as claimed in any one of claims 6 to 9 in which the, or both as the case may be, structural material panels have the same length and height as the insulation material panel.

A cast structural element as claimed in claim 10 in which the, or both as the case may be, structural material panels have the same thickness as the insulation material panel.

A cast structural element as claimed in any one of claims 6 to 1 1 in which the, or both as the case may be, insulation material panels extend from at least one end of the cast structural element by a predetermined length.

A cast structural element as claimed in claim 12 in which the, or both as the case may be, insulation material panels extend from both ends of the cast structural element by a predetermined length equal to half of a predetermined mortar gap between adjoining cast structural element in a wall or floor to be formed by a plurality of the cast structural elements, as the case may be.

A cast structural element as claimed in claim 12 in which the, or both as the case may be, insulation material panels extend from one end of the cast structural element by a predetermined length equal to that of a predetermined mortar gap between adjoining cast structural element in a wall or floor to be formed by a plurality of the cast structural elements, as the case may be.

A cast structural element as claimed in any one of claims 1 to 14 which includes at least one reinforcing rod transversely embedded in the structural element to extend through the sheet of insulation material and at least partly into the cast structural material.

A cast structural element as claimed in claim 6 or 7 which includes at least one reinforcing rod transversely embedded in the structural element to extend through the sheet of insulation material and at least partly into the one, or both as the case may be, structural material panels.

A cast structural element as claimed in claim 8 or 9 which includes at least one reinforcing rod transversely embedded in the structural element to extend through both sheets of insulation material and the centrally located third structural material panel and at least partly into each of the two outer structural material.

18. A cast structural element as claimed in any one of claims 1 to 17 which comprises a building block, preferably having ends with complimentary shaped and sized engaging formations.

A cast structural element as claimed in any one of claims 6 or 7 which comprises a building block having ends with complimentary shaped and sized engaging formations, in which the complimentary engaging formations are formed by the one structural material panel is aligned fully with the insulation panel and the other structural material panel is offset in the length of the building block to extend at one end beyond the end of the aligned structural material panel and insulation panel, and at the other end of the building block the end of the aligned structural material panel and insulation panel extend beyond the end of the offset structural material panel.

A cast structural element as claimed in claim 19 in which the length by which the offset structural material panel is offset from the aligned structural material panel and insulation panel corresponds to the combined thickness of the aligned structural material panel and insulation panel.

A cast structural element as claimed in claim 8 or 9 which comprises a building block having ends with complimentary shaped and sized engaging formations in which the complimentary engaging formations are formed by the building block having a stepped end at both ends along the longitudinal centre line of the third centrally located structural material panel to form a building block with steps of equal length at both ends.

A cast structural element as claimed in any one of claims 1 to 21 in which each structural material panel and each insulation panel has a thickness of about 40mm.

23. A cast structural element as claimed in any one of claims 1 to 22 provided with a finished surface on at least one of its sides.

24. A cast structural element as claimed in claim 23 in which the finished surface comprises a tile secured to its side.

25. A planar arrangement of structural elements comprising a plurality of structural elements as claimed in any one of claims 1 to 25 contiguously interlocked to form a single plane.

26. A tiled wall, floor or ceiling comprising a plurality of structural elements as claimed in claims 25 or 26 contiguously arranged end to end with their tiled surfaces all on one side.

27. An intersecting arrangement of three structural elements as claimed in any one of claims 6 or 7 that each comprises two structural material panels between which an insulation material panel is located, with their similar ends in abutment to form a single plane with a stepped channel at their abutting ends, with the complimentary end of a third similar structural element located in the channel in a substantially perpendicular relationship to the plane.

28. An intersecting arrangement of three structural elements as claimed in any one of claims 8 or 9, with their similar ends in abutment to form a single plane with a stepped channel at their abutting ends, with the complimentary end of a third similar structural element located in the channel in a substantially perpendicular relationship to the plane.

29. A method of making a cast structural element which includes locating a sheet of insulation material in a mould, casting a structural material into the mould, and allowing the product to cure for a predetermined period until stable.