EP0934157A1

EP0934157A1 - Reinforced surface element

Info

Publication number: EP0934157A1
Application number: EP96935606A
Authority: EP
Inventors: Roar Olsen
Original assignee: Thermozell Norge AS
Current assignee: Thermozell Norge AS
Priority date: 1995-10-17
Filing date: 1996-10-17
Publication date: 1999-08-11
Also published as: WO1997014556A1; NO954125D0; AU7345196A

Abstract

The use of a cement/concrete-reinforced polymeric synthetic material (1), preferably an expanded polystyrene substrate material, in combination with a non-carrying substrate (2) such as a rectifier material for producing a carrying laminate element for constructional purposes provides a structure with improved carrying properties. The laminate may be used alone or in combination with a basic plate element (4), and it may also be used in combination with a reinforcing web in any of the layers of the laminate structure.

Description

REENFORCED SURFACE ELEMENT

The present invention concerns a constructive element comprising a laminate of a cement/concrete-enforced poly- meric synthetic material e.g. EPS (Expanded Polystyrene ϋubstrate) granulate, PVC (Poly Vinyl Chloride) granu¬ late, PU (PolyUrethane) granulate etc., optionally as a foamed product, whereon there is added a layer of a sur¬ face-finishing material, e.g. a rectifier material such as liquid spac le, gypsum etc. It is preferred to use EPS granulate and liquid spackle as materials for the constructive element according to the present invention. If the concrete-reenforced polymeric synthetic material is used alone, synergistic effects are observed when such a material is poured onto a substrate comprising a non- carrying plate and allowed to harden. Such two or mul¬ tiple layered elements may be used as structural elements ^*and represent novel, light and easily handled construc¬ tive elements to be assembled on the construction site.

There are previously known constructive elements such as pre-fabricated walls, roofs etc., but such elements have in themselves no bracing or carrying properties, and may as such not be used for these purposes unless they are assembled in association with carrying structures such as enforcing walls, floor constructions etc. The present invention makes it possible to produce light enforced constructive elements wherein the enforcement effect is achieved by the synergistic effects existing between the materials used in the laminate structure of the elements.

The materials being part of the constructive element according to the present invention are previously known materials, but when such materials are combined in a laminate constructional structure, there are obtained properties which previously were not possible with these materials separately. The laminate structure according to the invention exhibit properties which are signifi¬ cantly improved in comparison with those properties which might be expected of such a construction in view of the properties of each of the components alone. Thus the constructive element according to the invention will exhibit synergistic properties concerning rigidity, iso- lational properties, carrying properties and holdfastness as compared to the previously known elements.

The disclosure infra refers to the accompanying figures 1 and 8 showing embodiments of the structure of construc¬ tional elements according to the invention.

According to the enclosed figures 1 and 8 the element 3 according to the invention comprises a layer 1 of a cement/concrete-enforced/stabilized synthetic material, e.g. a concrete-stabilized EPS granulate whereon there is placed a layer of a surface-finishing material, e.g. a rectifying material such as liquid spackle 2. In such a structure it is only required to use a layer of liquid spackle which is significantly thinner than the layers known from the prior art, and still obtain properties which previously were associated with significantly thicker elements. The thickness of the layer of liquid spackle 2 will, according to the present invention, lie when using concrete-stabilized PES and liquid spackle, in the interval 0,25 - 50 mm, e.g. in the interval 1 - 20 mm, more preferred in the interval 10 - 15 mm, most pre¬ ferred 8 - 12 mm.

In fig. 8 there is shown a constructional element 3 com¬ prising the above mentioned rectifyer material 2, the cement/concrete-reenforced polymeric synthetic material 1 as well as an additional plate element 4, shown as a corrugated plate element, onto which the materials com¬ prising the other layers of the laminate structure are laid/cast. When constructing a floor comprising a floor construction 3 according to the present invention, there is first laid out a layer of the concrete-stabilized EPS granulate to the wanted thickness to obtain the necessary insulting effect. The isolation may here be both sound and heat proofing.

According to prior art there has been placed a layer of concrete on top of such constructions to obtain the re- quired carrying strength. However, such a layer of con¬ crete is, with the synergistic effect between the compo¬ nents according to the present invention, quite redun¬ dant.

The surface of the concrete-stabilized EPS granulate becomes porous so that spackle material, when added to the construction, penetrates into the surface of the "concrete-stabilized EPS-granulate creating a synergistic effect with a significantly improved load distribution in the final surface. By applying liquid spackle with a thickness within the above indicated intervals, especial¬ ly with a thickness within 8 - 12 mm, there is obtained a carrying ability which is sufficient to satisfy the cur¬ rent requirements for floor constructions.

The elements according to the present invention will be illustrated infra with reference to a number of embodi¬ ments which are not to be regarded as limiting in any way.

Test 1: A combination of expanded polystyrene/concrete and liσuid spackle.

An element with this combination of components is shown in figure 1. On this figure there is shown a plate- formed element 3 comprising a layer 1 of a cement/concrete-stabilised EPS granulate whereupon there is placed a layer of liquid spackle 2. In such a con¬ struction it will only be required to use liquid spackle being significantly thinner than a corresponding layer of a previously known element without any basic EPS granu- late, and still obtain properties which previously were associated with much thicker elements. The data for this test are given infra.

The thickness of the layer of liquid spackle 2 will ac- cording to the present invention be in the interval

0,25 - 50 mm, e.g. in the area 1 - 20 mm, more preferred in the area 10-15 mm, most preferred 8-12 mm.

For producing floors comprising a floor constructional element 3 according to the present invention, there is first laid out, as is previously known, a layer of a cement/concrete-stabilised EPS granulate in the wanted -thickness to obtain the wanted isolational effect. The isolation may here be both sound and heat-proofing.

Previously there has been laid out a concrete layer onto such constructions for obtaining a proper carrying abil¬ ity, but as proven infra this will not be necessary by using a structure according to the present invention.

For this test there was used EPS-concrete (Thermozell) with a layer of spackle. There have been use two types of EPS-concrete specified as "Thermozell 250" and "Ther¬ mozell" 400. The indications "250" and "400" indicate the density of the EPS-concrete in dry condition being

250 kg/m³ and 400 kg/m³, respectively. The test does not include control measurements of the density of the samp¬ les. The type of spackle being used is the same for all the tests and has the trade mark "Straa Grov" supplied by Straa Norge A/S.

The following criteria have been used for evaluating the rigidity of the floor constructions. For light, sus¬ pended floors in normal habitation buildings a rigidity at a point load (0 25 mm) of 1 kN is considered to be good when the deflection is less than 1,5 mm, acceptable when the deflection 1,6 and 1,9 mm and poor when the deflection is larger than 2,0 mm. The deflection in edges and corners should be less than 1,5 mm with a load of 1 kN. According to the load standard NS 3479 the floor should be able to withstand a point load 1,5 kN with a load surface of 0 25 mm.

Industrial floors receive their dimensions according to the expected load, and shall, according to NS 3479, be able to accommodate a point load of 5,0 kN with a load area of 100 x 100 mm. All of the indicated plates have been tested with a load area 0 of 25 mm (point load) and 100 x 100 mm.

The number of plates tested is 6. The length and width of the test plates is 1,0 x 0,5 m. The plates consisting of the different types of concrete-reenforced EPS granu¬ late indicated supra, are equipped with a layer of spa¬ ckle on one side. Control measurements of the thickness of the layer of spackle on the different plates show great variations over the plate surface, see table 1. At the same time the spackle has penetrated somewhat into the foamed concrete on account of a relatively open sur¬ face structure.

Table 1

Indication of test samples showing the thickness of spac¬ kle and plate.

Plate Spackle thickness Plate thickness mm incl. spackle mm

No, 400/10 12 145 155 No. 2: 250/20 12 - 15 145 - 154

No. 3 : 250/10 8 - 12 135 - 140

No. 4: 400/10 12 - 15 141 - 146

No. 5: 400/20 8 - 12 160 - 166

No. 6: 400/20 8 - 12 162 - 165

As is observed from table 1 the thickness of both plate and spackle layer varied relatively considerably over the test samples. However, the samples are relatively repre¬ sentative for practical floor designs.

The test samples were exposed to stresses with a single point load with a load area of 0 25 mm and with an area of 100 x 100 mm. The load points were distributed over the test sample with a least distance from the plate edge of 50 mm. There were also conducted load/deformation measurements in the plate corners. On account of rela¬ tively inaccurately cast plates there have been performed at least 3 measurements for each load. For each measure¬ ment point there is drawn a load/deformation curve. All loads have been conducted up to the breaking load. When the load area is 0 25 mm, this was in the form of break¬ through, while the load area 100 x 100 mm gave a signifi¬ cantly larger deformation and cracking zone. The deform¬ ation for relevant working loads are read from the lo¬ ad/deformation curve.

Table 2 and 3 show the results from the tests

Table 2

Deflection and breaking load with a load area of 0 25 mm. Plate Measuring Load 0-1 Kn Break Deflection point (025 mm) load kN at break Deflection load mm mm (Approx lin- eary)

400/10 1 0,25 4,5 1,00

2 0,30 4,2 0,75

3 0,25 6,3 0,75

4 0,10 5,4 0,50

5 0,25 4,2 0,65

6 0,30 4,3 1,00

250/20 1 0,50 4,3 1,20

2 0,15 4,8 0,8

3 (deload) 0,15

3 0,15 4,3 0,6

250/10 1 0,25 3,5 1,3

2 0,20 3,5 0,9

3 0,20 3,5 0,7

400/10 1 0,10 5,4 0,7

2 0,10 6, 8 0,5

3 0,10 5,4 0,7

400/20 1 0,30 3,5 0,8

2 0,20 4,3 0,4

3 0,10 3,9 0,4

400/20 1 0,10 3,4 0,3

2 0,20 2,9 0,4 0,20 3,2 0,6

Table 2

Deflection at breaking point with a load area of 100 x

100 mm.

Plate Measuring Load 0-5 Kn Break Deflection point (lOOxlOOmm) load kN at break Deflection load mm mm (Approx lin- eary)

400/10 1 0,30 21,2 0,8

2 0,40 22,3 1,20

3 0,20 20,7 0,70

250/20 1 0,30 15,1 1,20

2 0,60 13,5 2, 00

3 0,50 11,4 1,50

250/10 1 1,10 13,3 1,60*

2 0,20 12,0 1,3

3 0,20 11,3 1,1

4 (corner) 0,60 17,1 1,0**

400/10 1 0,20 16,3 >2,0*

2 0,20 21,3 1,0

3 0,25 15, 8 1,1

4 (corner) 0,30 17,1 1,0

400/20 1 0,20 15,4 1,4

2 0,10 19,8 0,4

3 0,20 19,8 0,5

4 (corner) 0,50 17,5 1,7 400/20 1 0 , 20 15 , 5 1 , 0

2 0 , 20 16 , 9 0 , 6

3 0 , 20 16 , 6 0 , 8

* Crossing crack in the isolation (not covered with spackle) at approx. 6 kN on account of curved plate. ** Bad edge.

The relatively large variation in the measuring results for one and the same plate is mainly due to an uneven thickness of the spackle and to a lesser degree to the location of the measuring points. Some of the plates were relatively significantly curved, something which led to a crack in the middle of the plate during a load with the load area of 100 x 100 mm. However, this did not lead to any crack in the spackle layer and the plates maintained at the same time their strength. A measure¬ ment relevant to a corner is not very representative on account of bad edges on the test sample . The break load is read when there has been obtained a marked change in the working profile of the curve indicating an imminent crack.

As a conclusion of the results given supra for the mea¬ surements performed on the plates, all of the plates have a good margin concerning satisfying the specified cri¬ teria for evaluating the rigidity of the floor. Even the 250 plates could withstand a significant breaking load with a limited deflection. The spackle type which is used has the ability to penetrate somewhat into the sur¬ face of the foam concrete. The results thereof are great strength and a good load distribution. The results of the tests indicated supra proves that the laminate struc¬ ture formed according to the present invention may be used as structural elements without any need for further bracing structures. For an even more convincing test showing the synergistic effects of the cement/concrete-reenforced synthetic mate¬ rial in combination with a non-carrying plate element, a test was conducted with the concrete-reenforced polymeric synthetic material as indicated supra laid on top of a sheet of conventional corrugated iron ("Planja") . The test was performed by supporting the test material bet¬ ween two supports with a distance of 5,5 m between them. The test material was either the corrugated plate alone, the laminate structure of concrete-reenforced synthetic polymeric material (concrete-reenforced EPS) and the structural layer (liquid spackle) , a similar laminated structure with a reenforcement comprising a mesh (150*- 150*5) of a netting material or a combination of the unreenforced combination of concrete and polymeric syn¬ thetic material structure cast onto the corrugated plate. The measurements were taken at 7 points along the length of the test plate. Specifically the corrugated iron plate was a plate commercially available under the trade mark "Planja 111" with a thickness of 1,25 mm cast with a layer of "Thermozell 250" with a thickness of 100 mm. The length of the plate was 5,5 m and the width of the plate was 0,7 m. The structural material was left to harden for nine days whereafter the plate again was sub- jected to a load.

The results of the tests are shown in figs. 2 - 7.

The load on the plate elements was 200 kg/m². The maxi- mum deflection of the plates was reached with the corru¬ gated iron plate alone, showing a deflection of 39 mm.

The tests conducted with laminate materials of "Thermo¬ zell" and liquid spackle with and without any conven- tional reenforcement mesh, was performed to investigate if the reenforcement web improved the holdfastness of the structure. As is evident from the test results, the reenforcement web did not improve the holdfastness in the laminated structure comprising concrete-reenforced poly¬ meric synthetic material and liquid spackle, but the addition of "Thermozell" as compared to a "pure" corru¬ gated plate reduced the deflection of the plate with about 15 mm, something which is a significant and unex¬ pected reduction in the deflection.

A further test was performed in such a way that the test material was subjected to load only in the middle. The test was conducted to give an indication of how the con¬ crete-reenforced polymeric synthetic material ("Thermo¬ zell") would behave when breaking, how the plate would buckle and to investigate wether or not there appeared any split between the layers.

The test samples were subjected to successive loads up to 1000 kg, and then further with additional 1000 kg in a load up to 2000 kg. The deflection was in principle lineary from zero and up to 2000 kg. No visible changes in plate, concrete-reenforced polymeric synthetic materi¬ al ("Thermozell") or spackle was observed at the highest load when the test was finished.

The results of tests 1 - 4 is given infra.

"Planήa 111" without "Thermozell" (deflection in mm)

Measuring 140 kg/m² 200 kg/m² 240 kg/m² point

1 0

2 -18

3 -34

4 -39

5 -32

6 -19

7 0 "Plania 111" with "Thermozell 250 (unreenforced) (de¬ flection in mm)

Measuring 140 kg/m² 200 kg/m² 240 kg/m² point

1 0 0 0

2 -9 -12 -14

3 -13 -18 -21

4 -17 -22 -27

5 -16 -20 -23

6 -10 -13 -15

7 0 0 0

"Plania 111" with "Thermozell 250" (reenforced) (de¬ flection in mm) .

I Measuring 140 kg/m² 200 kg/m² 240 kg/m² point

1 0 0

2 -12 -15

3 -19 -21

4 -22 -26

5 -20 -24

6 -13 -15

7 0 0

"Plania 111" with "Thermozell 250" (un-reenforced) + spackle 20 mm (reenforced)

Measuring 140 kg/m² 200 kg/m² 240 kg/m² point 1 0

2 -3,9

3 -6,1

4 -6,7

5 -4,6

6 -4,3

7 0

The results from the tests show that the addition of a concrete-reenforced polymeric synthetic material to a non-carrying structure will improve the carrying proper¬ ties of the structure as a laminated structure in a sig¬ nificant way, and even better carrying properties will be obtained when adding a non-carrying finish to such a laminated structure or to the concrete-reenforced poly- jneric synthetic material alone.

Claims

C l a i m s

1. The use of a cement/concrete-reenforced polymeric synthetic material in combination with a non-carrying substrate for producing a carrying laminate element for constructional purposes.

2. Use according to claim 1, wherein the cement/con¬ crete-reenforced polymeric synthetic material wherein the non-carrying substrate is a plate element.

3. Use according to claims 1 or 2 wherein the ce- ment/concrete-reenforced polymeric synthetic material is used in combination with a non-carrying substrate in association with a basic plate element.

4. Use according to any of the preceding claims wherein ^* the cement/concrete-reenforced synthetic polymeric mate¬ rial is an EPS-granulate.

5. Use according to any of the preceding claims wherein the non-carrying substrate is spackle, preferably liquid spackle.

6. Use according to any of the preceding claims wherein the laminate structure is used on combination with a reenforcing web in any of the laminate layers of the structure.

7. Constructional plate element, c h a r a c t e r i z e d i n that it comprises a cement/concrete-reenforced polymeric synthetic material laminated to a non-carrying substrate material.

8. Constructional plate element according to claim 7, c h a r a c t e r i z e d i n that the non-carrying substrate material is spackle, preferably liquid spackle.

9. Constructional plate element according claim 7, c h a r a c t e r i z e d i n that non-carrying sub¬ strate material is a plate element.

10. Constructional plate element according to claim 7, c h a r a c t e r i z e d i n that the laminate stru¬ cture is used in combination with a basic plate element or vice versa.

11. Constructional plate element according to any of the claims 7 - 10, c h a r a c t e r i z e d i n that any of the layers in the laminate construction comprises a reenforcing web material.

12. Constructional plate element according to any of the claims 7 - 11,

'c h a r a c t e r i z e d i n that the cement/con- crete-reenforced polymeric synthetic material is a ce- ment-stabilized EPS granulate.

13. Constructional plate element according to any of the claims 7 - 12, c h a r a c t e r i z e d i n that the liquid spackle comprises a layer with a thickness of 0,25 - 50 mm, pre¬ ferably 8 - 12 mm.

1 . Constructional plate element according to any of the claims 7 - 13, c h a r a c t e r i z e d i n that the layer of the cement/concrete-reenforced polymeric material is 130 - 150 mm thick.