WO2007147178A2

WO2007147178A2 - A construction element

Info

Publication number: WO2007147178A2
Application number: PCT/ZA2007/000035
Authority: WO
Inventors: Allen Michael Tucker
Original assignee: Allen Michael Tucker
Priority date: 2006-06-14
Filing date: 2007-07-02
Publication date: 2007-12-21
Also published as: WO2007147178A3

Abstract

The invention provides a construction element or panel (10) which has an outer cementitious layer (12), a reinforcing scrim (14) which is at least partially embedded in the outer layer, an intermediate cementitious layer (16) which is bonded to the outer layer and an insert (18) which is bonded to the intermediate layer and to the outer layer through the intermediate layer.

Description

A CONSTRUCTION ELEMENT

BACKGROUND OF THE INVENTION

[0001] The invention relates to a construction element such as a panel for use in the construction of buildings and structures and a method of manufacturing of the construction element.

[0002] Lightweight building elements and panels are known. In various applications it is important that these elements have outer surface properties similar to those of heavy elements constructed from traditional cementitious, brick, clay or stone materials.

[0003] Lightweight cementitious panels are prone to cracking and breaking which are unsightly and might render the panels useless.

SUMMARY OF THE INVENTION

[0004] This invention aims to provide an alternative lightweight construction element and a method of manufacturing thereof which might alleviate some of the aforementioned problems.

[0005] The invention provides a construction element which includes an outer cementitious layer, a reinforcing scrim which is at least partially embedded in the outer layer and a lightweight cementitious insert which is bonded to the outer layer.

[0006] The outer layer may include a filler. The filler may include polypropylene which

is preferably fluorinated. [0007] The insert may be foamed or may include expanded polystyrene.

[0008] The construction element may include an intermediate cementitious layer which is bonded to the outer layer and to the insert. Preferably the scrim is at least partially trapped between the outer layer and the intermediate layer.

[0009] The invention also provides a method of manufacturing of a construction element which includes the steps of:

(a) applying an outer cementitious layer to a first mould surface

(b) at least partially embedding a fibreglass reinforcing scrim into the outer layer;

(c) allowing the outer layer to at least partially set; and

(d) bonding a lightweight cementitious insert with the outer layer.

[0010] The outer layer may include a filler. The filler may include polypropylene which is preferably fluorinated.

[0011] The first mould surface may include ornamentation or may be textured.

[0012] The insert may be foamed or may include expanded polystyrene.

[0013] The method of manufacturing may include the step of bonding an intermediate cementitious layer to the outer layer and to the insert.

[0014] The method of manufacturing may include the step of at least partially trapping the scrim between the outer layer and the intermediate layer. O

[0015] The method of manufacturing may include the step of engaging the first mould surface with a second similar mould surface to form a cavity between the opposing outer layers on the respective surfaces.

[0016] The method of manufacturing may include the step of filling the cavity with the insert.

[0017] The method may include the step of allowing the outer layers and the insert to set.

[0018] The method may include the steps of disengaging the first mould surface from the second mould surface and the outer layer and disengaging the second mould surface from the outer layer.

[0019] The invention also provides a wall which includes a foundation, a plurality of spaced apart pillars wherein each pillar extends from the foundation and has at least one vertical slot, a plurality of construction elements of the aforementioned kind wherein each element extends between adjacent pillars and is at least partially located in the slot and an elongate coping member which has an elongate, horizontal recess wherein the panel is at least partially received.

[0020] The panel may be embedded in the foundation.

[0021] The coping member may extend on top of the panel between the adjacent pillars. ^

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The invention is further described by way of examples with reference to the accompanying drawings in which :

Figure 1 is a cross-sectional side view of a construction element or panel according to the invention;

Figure 2 is a perspective view of a first mould used in the manufacturing of the panel of Figure 1 ;

Figure 3 is a perspective view of an enclosed mould body which is used in the manufacturing of the panel of Figure 1 ;

Figure 4 is a perspective view of a wall which is manufactured from the panels of Figure

1;

Figure 5 is a front side view of the wall of Figure 4;

Figure 6 is a cross-sectional view from above of the wall of Figure 5 on the line 6-6 shown in Figure 5; and

Figure 7 is a cross-sectional side view of the wall of Figure 4 on the line 7-7 shown in

Figure 5.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0023] Figure 1 illustrates a planar construction element or panel 10 which has an outer cementitious layer 12, a reinforcing scrim 14 which is at least partially embedded in the outer layer 12, an intermediate cementitious layer 16 which is bonded to the outer layer 12 and an insert 18 which is bonded to the intermediate layer 16 and to the outer layer 12 through the intermediate layer 16. [0024] The panel 10 has a width W of between 30mm to 50mm, a height H of between 1600mm to 2000mm and a length L of between 2500mm and 2800mm. The outer layer 12 has a thickness T1 of between 2mm to 5mm, the intermediate layer 16 has a thickness T2 of between 2mm and 5mm and the insert 18 has a thickness T3 of between 20mm to 45mm.

[0025] The outer layer 12 is made from high strength Portland cement which is mixed with a filler such as sand and/or fluorinated polypropylene. Polypropylene and especially fluorinated polypropylene enhances the flexibility of the outer layer 12 and protects the outer layer 12 against cracking.

[0026] The scrim 14 is made of woven fibreglass or fluorinated polypropylene. It is important that the scrim 14 is made from a non-ferrous material as ferrous materials are prone to corrosion when brought into contact with Portland cement accelerants and corrosive environments. The scrim 14 is of high strength and has good cohesion with the outer layer 12. Importantly the scrim 14 is elastic.

[0027] The intermediate layer 16 is made from the same material as the outer layer 12.

[0028] The insert 18 is made from a mixture of Portland cement and an appropriate filler or foaming agent. As a filler expandable polystyrene can be used.

[0029] The panel 10 has a robust exterior formed by the outer layer 12 which can be shaped, handled and worked in the same manner as any other high strength cementitious product. The panel 10 is relatively lightweight and is transportable. Despite a high slendemess ratio the panel 10 is substantially rigid but is flexible to a limited degree without cracking or breaking. This is caused by the fact that the reinforcement of the panel 10 by way of the scrim 14 is close to an outer surface of the panel 10. The reinforced shell of the panel 10 which consists of the outer layer 12, the scrim 14 and the intermediate layer 16 surrounds the insert 18 and provides substantial rigidity and strength to the panel 10.

[0030] As the scrim 14 is made from a non-ferrous material the ingress of water into the panel 10 does not result in corrosion of the scrim 14 and the possible separation of the scrim 14 from the outer layer 12. Accordingly the panel 10 can be used in exterior applications and in hostile environments.

[0031] As is illustrated in Figures 2 and 3 the panel 10 is manufactured by way of two identical and opposing moulds 20. Each mould 20 has a mould surface 22 which is surrounded by side walls 24. A semicircular inlet 26 is formed in a wall 24A at one end of the mould 20. The mould 20 is made from any appropriate material and the mould surface 22 includes surface ornamentation or texturing 28 which is used to impart a required ornamentation or texture to the outer layer 12. The cementitious material of the outer layer 12 is sprayed onto the mould surface 22 and walls 24 while in liquid format. The material adheres to the inside of the moulds 20 to form the outer layer 12. Thereafter an appropriately sized scrim 14 is brought into contact with the outer layer 12 and at least partially embedded in the outer layer 12. The cementitious material of the intermediate layer 16 is thereafter sprayed onto the scrim 14 and the outer layer 12 while in a liquid format so that the scrim 14 becomes trapped between the outer layer 12 and the intermediate layer 16 and the intermediate layer 16 bonds to the outer layer 12. [0032] At this point the outer layer 12 and intermediate layer 16 are allowed at least partially to set while the mould 20 lies in a horizontal position.

[0033] The same procedure is followed in respect of a second mould 2OA and once the outer layers 12, 12A and intermediate layers 16, 16A on the mould 20 and the second mould 2OA have partially set the mould 20 and the second mould 20A are brought together at their respective walls 24 and interengaged in the manner shown in Figure 3.

[0034] The mould 20 and the second mould 2OA are locked to one another in this position in any appropriate manner. The combined mould 20 and second mould 2OA form an enclosed mould body 30. The mould body 30 is placed in a vertical orientation so that the opposing inlets 26 face upwards. Alternatively the mould body 30 is laid in a horizontal position. In this manner a cavity 32 is formed in the mould body 30 between the opposing outer layers 12, scrims 14 and intermediate layers 16. The cavity 32 is filled by pouring or pumping liquid material of the insert 18 into the cavity 32 through the inlets 26. As the material of the insert 18 flows into the cavity 32 it contacts with and bonds to the intermediate layer 16. In this manner the insert 18 becomes bonded to both the intermediate layer 16 and the outer layer 12 by way of the intermediate layer 16.

[0035] Once the cavity 32 is filled the outer layer 12, intermediate layer 16 and insert 18 are allowed to set. Once the outer layer 12, intermediate layer 16 and insert 18 have set the mould 20 and mould surface 22 are disengaged from the second mould 2OA and the outer layer 12. Thereafter the second mould 2OA and mould surface 22A are disengaged from the outer layer 12. O

[0036] The resulting product is the panel 10 of Figure 1.

[0037] The intermediate layer 16 is optional and can be omitted from the panel 10. In this case the insert 18 is in direct contact with and bonded to the outer layer 12 and the scrim 14 is at least partially trapped between the outer layer 12 and the insert 18.

[0038] By varying the ornamentation and texturing on the mould surface 22 any required surface ornamentation or texturing can be imparted to the outer layer 12.

[0039] By mixing appropriate colorants and fillers with the material of the outer layer 12 the texture and colour of the panel 10 can be varied.

[0040] The panel 10 can be used in the construction of various buildings and structures and has high insulation, fire resistant and impact resistance characteristics.

[0041] Figures 4 to 7 illustrate the use of the panel 10 in the construction of a wall 50. The wall 50 has a base or foundation 52, a plurality of spaced apart pillars 54, a cap 56 on each pillar 54, a panel 10 which extends between each pair of adjacent pillars 54 and an elongate coping member or tile 58 which is positioned on each panel 10 and which extends between the adjacent pillars 54.

[0042] The foundation 52 is made from concrete and is cast in a trench 60 in for example the ground 62 in a known manner.

[0043] Each pillar 54 is inserted vertically into the foundation 52 before same has set. Each pillar 54 is square or rectangular shaped in cross section and has two elongate and vertical slots 64 which extend in the pillar 54 for a substantial portion of its length. y

Each slot 64 is dimensioned so that a panel 10 can fit snugly and at least partially into the slot 64 so that the panel 10 can at least partially be trapped in the slot 64.

[0044] Depending on requirement a pillar 54 at the end of the wall 50 can have a single slot 64. Accordingly each pillar 54 has at least one slot 64.

[0045] Each of the pillars 54 is manufactured in the same manner as the panel 10 and, except for its dimensions, has a similar structure to that of the panel 10.

[0046] The cap 56 is known and fits over the upper end of the pillar 54.

[0047] Each panel 10 is fitted into the slot 64 of each of the opposing pillars 54 and is also at least partially embedded into the wet foundation 52.

[0048] In this position the pillars 54 and the panels 10 are supported in any appropriate manner in order for the foundation 52 to set.

[0049] The tile 58 has an elongate and horizontal recess 66 which is complementary shaped to a top 68 of the panel 10 so that the top 68 of the panel 10 fits at least partially into the recess 66. In this manner the panel 10 is at least partially received and trapped within the recess 66 of the tile 58 and the tile 58 extends on top of the panel 10.

[0050] The cap 56 and tile 58 are respectively fixed to each pillar 54 and panel 10 in any appropriate manner and can for example be bolted or glued.

[0051] Once the foundation 52 has set and the tile 58 has been fitted to the panel 10, each panel 10 is framed on its respective sides by the foundation 52, opposing pillars 54 and the tile 58. The framing rigidifies and strengthens the panel 10 along its border and limits possible buckling of the panel 10 against sideways and downward pressures on the panel 10.

[0052] As a result of the lightweight construction of the panels 10 and the pillars 54 a light foundation 52 can be used.

[0053] Because of variations in the surface ornamentation or texturing 70 on the outer layer 12 of the pillars 54 and panels 10 the wall 50 can have different appearances resembling different finishes.

[0054] In most applications the wall 50 requires less construction time and is less expensive than walls with similar finishes which are built by hand and from traditional materials which give a similar finish.

Claims

1. A construction element which includes an outer cementitious layer, a reinforcing scrim which is at least partially embedded in the outer layer and a lightweight cementitious insert which is bonded to the outer layer.

2. A construction element according to claim 1 wherein the outer layer includes a filler.

3. A construction element according to claim 2 wherein the filler includes polypropylene.

4. A construction element according to claim 3 wherein the polypropylene is fluorinated.

5. A construction element according to any one of claims 1 to 4 wherein the insert is foamed.

6. A construction element according to any one of claims 1 to 5 wherein the insert includes expanded polystyrene.

7. A construction element according to any one of claims 1 to 6 which include an intermediate cementitious layer which is bonded to the outer layer and to the

insert.

8. A construction element according to claim 7 wherein the scrim is at least partially trapped between the outer layer and the intermediate layer.

. A method of manufacturing of a construction element according to claim 1 which includes the steps of:

(a) applying the outer layer to a first mould surface;

(b) at least partially embedding the scrim into the outer layer;

(c) allowing the outer layer to at least partially set; and

(d) bonding the insert with the outer layer.

10. A method according to claim 9 wherein the outer layer includes a polypropylene filler.

11. A method according to claim 9 or 10 wherein the first mould surface includes ornamentation.

12. A method according to claim 9, 10 or 11 wherein the first mould surface is textured.

13. A method according to any one of claims 9 to 12 which includes the step of bonding an intermediate cementitious layer to the outer layer and to the insert.

14. A method according to claim 13 which includes the step of at least partially trapping the scrim between the outer layer and the intermediate layer.

15. A method according to any one of claims 9 to 14 which includes the step of engaging the first mould surface with a second similar mould surface to form a cavity between the opposing outer layers on the respective surfaces.

16. A method according to claim 15 which includes the step of filling the cavity with the insert.

17. A method according to claim 15 or 16 which includes the step of allowing the outer layers and the insert to set.

18. A method according to claim 15, 16 or 17 which includes the steps of disengaging the first mould surface from the second mould surface and the outer layer and disengaging the second mould surface from the outer layer.

19. A wall which includes a foundation, a plurality of spaced apart pillars wherein each pillar extends from the foundation and has at least one vertical slot, a plurality of construction elements according to claim 1 wherein each element extends between adjacent pillars and is at least partially located in the slot and an elongate coping member which has an elongate, horizontal recess wherein the panel is at least partially received.

20. A wall according to claim 19 wherein the panel is embedded in the foundation.

21. A wall according to claim 19 or 20 wherein the coping member extends on top of the panel between the adjacent pillars.