EP2281964A1 - Cast wall, floor or ceiling element and manufacturing method thereof - Google Patents

Abstract

The cast wall, floor or ceiling element has a wall (13) with a thickness and another wall (15) with another thickness. An insulating layer (17) is provided between the former and latter walls. The cast wall, floor or ceiling element is made of hardenable casting material of cement basis, particularly light concrete. The element is made of a light concrete with an oven-dry density. An independent claim is also included for a method for manufacturing a concrete wall.

Description

The present invention relates to a cast wall, floor or ceiling element according to the preamble of claim 1 and a method for its production.

State of the art

For exposed concrete structures (exterior wall and interior wall with exposed concrete), the process to date is to first concretise an internal load-bearing shell, then allow the concrete to harden, then remove the formwork, place an insulation level, then form the formwork for the external formwork and again concreted. The whole thing is very time consuming and expensive because of the many operations that are necessary for the creation of the building. A second variant provides that you create a single-shell construction with internal insulation. However, this has the following disadvantages: 1. very many expensive connection details, e.g. In the case of multi-storey buildings, there is a thermal bridge in the area of the ceiling, which can only be laboriously insulated. 2. the lack of storage mass inside the building. This means that solar profit entries can not be used by opaque components in favor of a lower heating demand.

The US 2001/0010140 discloses a building part comprising two parallel, spaced-apart wire mesh, between which an insulating body is arranged. Straight connecting rods, whose ends are welded to the wire mesh, penetrate the insulating body and keep the wire mesh at a distance from each other. The insulating body can be made of foamed plastic, of other insulating materials of various kinds or lightweight concrete. Between the wire mesh and the insulating body is a distance between 10 and 30 mm. In the case of right-angled connecting rods spacers are additionally provided, which space the insulating body of the wire mesh. In the finished component, such as a wall, which is cast on site, the wire mesh are included in the hardened concrete. Depending on the static requirements, the inner and outer walls can have different strengths.

The DE-OS-197 48 457 discloses a thermally insulated, supporting outer wall element in a multi-layer sandwich construction. This consists of a serving as a support inner wall, an outer wall spaced therefrom and a thermal insulation layer disposed between the walls. Both exterior and interior walls are made of lightweight LB15 grade concrete. As a thermal insulation layer is also a polyurethane or Polystyrene foam in questions. The outer and inner walls are firmly connected to each other via intersecting coupling rods whose corrugated ends are embedded in lightweight concrete. By this construction it is ensured that the outer wall element is torsionally rigid and can be raised for example on the support layer.

US 2006/0201090 discloses a lightweight composition consisting of from 22 to 90% by volume of a cement composition and from 10 to 78% by volume of particles having a density between 0.03 g / cm 3 and 0.064 g / cm 3. Insulated concrete elements consist of two parallel, spaced-apart walls, which are interconnected by metal bars. The space between the walls is filled with a lightweight concrete.

task

Object of the present invention is to provide a particular cast on site wall, floor or ceiling element, in particular a fair-faced concrete element, which has the best possible insulation value for a given wall thickness. The aim is in particular to propose a cast and insulated wall and a method for their production, which can be produced quickly and inexpensively. It is also an objective to propose a monolithic wall both on the inside and on the outside in exposed concrete quality.

According to the invention, the object is achieved by a cast wall, floor or ceiling element according to the preamble of claim 1 by using as insulation layer materials, preferably insulation boards, with a compressive stress at 10% compression σ ₁₀ ≥ 60 kPa, preferably σ ₁₀ ≥ 150 kPa, and most preferably σ ₁₀ ≥ 300 kPa are used. The element according to the invention as a locally cast component of a building, in particular a building, has the advantage that it can be produced quickly and inexpensively as a fully insulated component, since it can be cast in one operation. The insulation is designed so that it is not compressed by the static pressure of the still liquid lightweight concrete. Since the insulation in the element is already integrated, a subsequent insulation is no longer necessary. The fact that the outer wall has less than half as much and advantageously less than one third of the thickness of the inner wall and serves only as a veneer, it needs only a few coupling bracket to secure the outer wall, especially because the device as part of a larger Building construction is poured on site. Due to the small number of coupling bracket only a few thermal bridges, so that the construction is surprisingly able to meet the requirements in the manufacture of passive houses. The inventive wall, floor or ceiling element has the advantage that it can be produced both on the inside and on the outside in exposed concrete quality and thus can meet the requirements of modern architecture.

The lightweight concrete element with a dry density of at most 2000 kg / m 3, preferably <1500 kg / m 3 and very particularly preferably <1200 kg / m 3, is advantageous. is made. The use of lightweight concrete eliminates the risk that the insulating layer will be compressed. Accordingly, inexpensive available insulation materials can be used. Conveniently, the casting material used is essentially made of cements, binders, foam glass or expanded clay as an additive, and mixing water and additives (additives). A lightweight concrete with foam glass as an additive is for example in the EP-A-1 183 218 , the contents of which are hereby incorporated by reference.

According to a preferred embodiment, the first wall is designed as the static support structure and the second wall as a veneer. In this case, a blanket may be supported on the inner tray, and the outer second wall may be relatively thin. The second outer wall may, for example, have a thickness between 40 and 140 or 160 mm, preferably 50 to 120 or 140 mm and most preferably between 60 and 100 or 120 mm. Due to the fact that the inner wall or shell is more strongly formed, that is to say the outer shell, a large storage mass is present in the interior of the building. This has the advantage that solar gains can be stored by opaque components of the inner shell. However, it is conceivable to assign the outer wall a supporting function and the ceiling, for example. partially supported on the outer shell by cam-like removal. In this case, the outer wall can be carried over the entire surface or supporting only in partial areas. If only one wall has a supporting function, they can have different strengths.

Preferably, the first wall has a reinforcement made of steel, which is preferably arranged centrally or symmetrically to the system axis in the wall. This has the advantage that shrinkage stresses can not lead to deformation of the wall. Advantageously the reinforcement at least two approximately parallel planes, which by means of spacers, for example by three-dimensional reinforcing baskets or blocks, are firmly connected. These planes are preferably approximately equidistant from the central axis of the wall. The deployable three-dimensional reinforcing bars can be triangular in cross-section, wherein in the corners longitudinally extending rods are present. Such reinforcing blocks are used for example in concrete ceilings.

Conveniently, prefabricated reinforcing steel nets or metal baskets, which represent a stable three-dimensional structure used. Of importance is that the metal baskets are inherently stable and are not compressed by the filled in liquid concrete. The reinforcement layers should not be displaced to each other and in their position within the formwork through the concrete.

Advantageously, at least the second wall only has a reinforcement formed by fibers. Preferably, polymer fibers are used in the form of short cut fibers. This has the advantage that can be dispensed with a reinforcement made of reinforcing steel in the second wall. This leads to a significant time savings in the production of the insulated wall. In this case, the proportion of polymer fibers in the second wall between 0.4 to 2.0 Kg / m3, preferably between 0.5 to 1.5 Kg / m3, and most preferably between 0.6 and 1.2 Kg / m3 amount.

Polymer fibers are particularly advantageously a highly crystalline polymer, preferably from the group of polyvinyl alcohols used. These fibers have the advantage that they can form chemical bonds with the casting compound. The polymer fibers used are preferably those which have a tensile strength> 1,000 N / mm 2, preferably> 1,200 and very particularly preferably> 1,500 N / mm 2 and an E modulus> 30,000 N / mm 2, preferably> 35 '. 000 N / mm 2, and most preferably> 40,000 N / mm 2.

Insulating layer materials are advantageously used which have a thermal conductivity (lambda D value = λ _D ) ≤0.04 W / mK, preferably ≤ 0.035 W / mK and very particularly preferably ≤ 0.03 W / mK. Ideally, insulation boards with a thermal conductivity ≤ 0.029 W / mK are used. As materials in particular plastics with the exception of polyurethane or mineral fibers (rock wool or glass fiber) in question. However, mineral fibers must be treated in such a way that the Water absorbency is reduced to an acceptable level. In a preferred embodiment, the insulating layer consists essentially of polystyrene, preferably an expanded or extruded polystyrene rigid foam. Polystyrene insulation boards are available at low cost and generally have sufficient compressive strength.

According to a preferred embodiment insulation boards are used as an insulating layer, which are preferably equipped with a groove and comb. This has the advantage that the insulation can not be moved against each other. It is also conceivable to use the largest possible possible insulation boards. It can be used depending on floor height plates with different compressive strengths. Plates with a σ ₁₀ between about 100 kPa and 250 kPa are ideal since they are relatively inexpensive. It is also advantageous if the insulation boards used as insulating layer have a water vapor diffusion number ≤ ∞, preferably ≤ 250 μ, and most preferably ≤ 50 μ. This is in connection with the use of lightweight concrete advantageous because it ensures the diffusion-open nature of the entire construction and can diffuse out in the dew point, condensed water.

In order not to impair the drying of the cast element, the water absorption capacity of the insulating layer should be <4% by volume, preferably <1.0% by volume and very particularly preferably <0.2% by volume. Ideally, the water absorption capacity is 0 V% measured according to the test standard EN 12087. It is important that in case of any water absorption, the insulation board is dimensionally stable. Otherwise, it can lead to tensions and deformations of the cast wall. To avoid shrinkage stresses, the casting compound is preferably admixed with shrinkage reducing agents.

Advantageously, the first wall and the second wall are connected to each other by means of coupling brackets, preferably by means of stainless steel. This can prevent the walls from coming off each other. The coupling straps may have, for example, a U, V, L, T or Z shape. The coupling bracket can basically be installed at any angle to the flat sides of the wall. Preferably, however, they extend approximately perpendicular to the flat sides of the wall. Conveniently, 0.1 to 0.6 coupling bracket, preferably 0.2 to 0.4 coupling bracket are provided per square meter. The coupling brackets can be made from structural steel, stainless steel or, advantageously, reinforced from a glass, carbon fiber or plastic fiber Be made of plastic. The latter coupling bracket have the advantage over steel of significantly lower thermal conductivity.

Advantageously, the cured element has a thermal conductivity <0.16 W / mK.

• Erstellen einer ersten, vorzugsweise ungefähr vertikalen, Schalungswand,
• Anbringen einer ersten Bewehrungslage aus Stahl in Abstand von der ersten Schalungswand,
• Anbringen von Distanzmitteln, vorzugsweise in Gestalt von Distanzkörben, an der ersten Bewehrungslage,
• Anbringen einer zweiten Bewehrungslage aus Stahl an den erwähnten Distanzmitteln,
• Anordnen einer Dämmschicht mit einer Druckspannung bei 10% Stauchung von σ₁₀≥ 60 kPa, vorzugsweise σ₁₀≥ 150 kPa, und ganz besonders bevorzugt σ₁₀≥ 300 kPa in Abstand von der zweiten Bewehrungslage, welche Dämmschicht eine Fläche hat, die im Wesentlichen der Fläche der ersten Schalungswand entspricht, sodass ein erster Schalungsraum mit Bewehrung gebildet ist,
• Einbringen von einer Mehrzahl von Kopplungsbügeln, welche sich durch die Dämmschicht erstrecken und diese beidseits um eine bestimmte Distanz überragen,
• Erstellen einer zweiten Schalungswand, sodass zwischen der Dämmschicht und der zweiten Schalungswand ein zweiter Schalungsraum ohne Bewehrung gebildet ist,
• Ausgießen des Schalungsraumes zwischen der ersten Schalungswand und der zweiten Schalungswand mit einer aushärtbaren Gussmasse, wobei die Schalungsräume im Wesentlichen gleichzeitig oder mit leichtem Vorlauf für den zweiten Schalungsraum mit der aushärtbaren Gussmasse gefüllt werden, sodass nach dem Aushärten der Gussmasse eine erste Wand und eine zweite Wand gebildet sind. Das erfindungsgemässe Verfahren hat den Vorteil, dass eine Wand mit einer Kerndämmung in einem Arbeitsgang direkt auf der Baustelle hergestellt werden kann. Im Rahmen des beschriebenen Verfahrens ist es auch möglich, ein dreidimensionales Bewehrungsgefüge mit mindestens zwei Ebenen in einem Verfahrensgang einzubringen. Zwischen der ersten Schalungswand und der ersten Bewehrungslage einerseits und der zweiten Bewehrungslage und der Dämmschicht andererseits werden vorteilhaft Distanzhalter eingesetzt, damit die Bewehrung ausreichend tief im Beton eingebettet ist.

The subject matter of the present invention is also a method for producing a concrete wall cast on site with the following method steps:

• Creating a first, preferably approximately vertical, formwork wall,
• Attaching a first reinforcing layer of steel at a distance from the first formwork wall,
• Attaching spacers, preferably in the form of spacer baskets, to the first reinforcement layer,
• Attaching a second steel reinforcing layer to said spacer means,
• Arranging an insulating layer with a compressive stress at 10% compression of σ ₁₀ ≥ 60 kPa, preferably σ ₁₀ ≥ 150 kPa, and most preferably σ ₁₀ ≥ 300 kPa at a distance from the second reinforcement layer, which insulating layer has an area substantially Surface of the first formwork wall corresponds, so that a first formwork space is formed with reinforcement,
• Introduction of a plurality of coupling straps, which extend through the insulating layer and project beyond it on both sides by a certain distance,
• Creating a second formwork wall so that a second formwork space without reinforcement is formed between the insulation layer and the second formwork wall,
• Pouring the formwork space between the first formwork wall and the second formwork wall with a curable casting material, wherein the formwork spaces are filled substantially simultaneously or with a slight flow for the second formwork space with the curable casting material, so that after curing of the casting material, a first wall and a second wall are formed. The inventive method has the advantage that a wall with a core insulation can be made in one operation directly on the site. In the context of the method described, it is also possible to introduce a three-dimensional reinforcement structure with at least two levels in a single process. Spacers are advantageously used between the first shuttering wall and the first reinforcement layer on the one hand and the second reinforcement layer and the insulating layer on the other hand, so that the reinforcement is embedded sufficiently deep in the concrete.

The attachment of the insulating layer to the second reinforcement layer is preferably carried out by means of plastic dowels, as used in the attachment of insulation layers to facades. The front ends of the plastic dowels can be tied to the second reinforcement layer with a binder. Other fasteners and types of attachment are also conceivable.

Preferably each on site, i. On the construction site, cast wall, floor or ceiling element of the present invention can basically be used as a vertical component (wall) or as lying component (plate). Accordingly, in the context of the present invention, the term "wall" in each case also "plates" are understood. In the latter case, the element is cast horizontally by first casting a disc, then applying the insulating layer and then casting the second disc.

Figur 1

im Grundriss ein Ausführungsbeispiel eines erfindungsgemässen Wandelements mit einer ersten Wand, welche in der Regel die Innenwand darstellt, einer zweiten Wand, welche in der Regel die Aussenwand darstellt, und einer zwischen den ersten und zweiten Wänden eingegossen Dämmschicht;

Figur 2

ein Schnitt durch das Wandelement von Figur 1 entlang der Linie A - A;

Figur 3

ein Schnitt durch das Wandelement von Figur 1 entlang der Linie B - B;

Figur 4

ein vergrösserter Vertikalschnitt durch die Wand von Figur 1; und

Figur 5

ein vergrösserter Horizontalschnitt durch die Wand von Figur 1.

The invention will be explained below by way of example with reference to the figures. It shows:

FIG. 1

an outline of an embodiment of an inventive wall element with a first wall, which usually represents the inner wall, a second wall, which usually represents the outer wall, and a cast between the first and second walls insulating layer;

FIG. 2

a section through the wall element of FIG. 1 along the line A - A;

FIG. 3

a section through the wall element of FIG. 1 along the line B - B;

FIG. 4

an enlarged vertical section through the wall of FIG. 1 ; and

FIG. 5

an enlarged horizontal section through the wall of FIG. 1 ,

That in the FIGS. 1 to 3 shown wall element 11 has a first wall 13, which usually represents the inner wall of a multi-shell wall, and a second wall 15, which is usually the outer wall of a multi-walled wall. Between the first and the second wall 13,15 an insulating layer 17 is arranged, which is in conjunction with the first and second walls 13,15. The first wall 13 is provided with a reinforcement 19 made of reinforcing steel. The reinforcement 19 preferably consists of a three-dimensional, inherently stable structure, for example a steel wire basket. The reinforcement 19 has two each arranged in a plane wire or reinforcing steel networks (= reinforcing), which are spaced apart by means of spacers 21, preferably a three-dimensional reinforcing cage made of structural steel rods. The use of a three-dimensional reinforcing cage has the advantage that the inner wall can have a high static load capacity. At the lateral ends of the two levels of wire or iron nets are connected by means of U-shaped bracket 23 with each other, so that a per se stable wire or reinforcing steel basket is formed. Preferably, the reinforcement consists of overlapping reinforcement steel meshes 24 (FIG. Fig. 2 ).

How out FIG. 1 it can be seen, the first and second walls 13,15 are connected to each other by means of a plurality of wind anchors 25. The wind anchors 25 may have a U, Z, or any other shape that ensures that the ends of the wind anchors 25 can not be pulled out of the walls under tensile load.

A wall or panel element according to the invention is produced as follows: First shuttering means 27, e.g. in the form of rails, arranged and attached to the reinforcement 19 ( FIGS. 4 and 5 ). At the distance holding means 27 opposite side of the reinforcement 19 second distance holding means 29, also preferably in the form of rails, attached. Then, the insulating layer 19 is disposed on the second distance-retaining means 29 and fixed by means of plastic dowels 31 to the reinforcement 19 or the rails. As plastic dowel 31 can be used as they are used for the attachment of insulation boards to facades for use. These dowels have a head 33 with a large contact surface. The attachment of the dowel shaft can be done for example by a wire 35. Between individual insulation elements wind anchor 25 can be inserted, which protrude with their ends on opposite sides of the insulation layer. Subsequently, a second shuttering wall is then arranged at a distance from the first shuttering wall and the insulating layer (not shown in the figures). The formwork walls are, depending on the formwork system, for example, by means of binding points and connecting pipes (spacers) 37 and then filled the formwork cavities between the shuttering walls and the insulating layer 19 with a lightweight concrete mixture.

Wall example (mass in cm):

Total wall thickness: 44 Inner pane: 16 Reinforcement mesh 4-ply with spacers: Outer pane without reinforcing mesh: 12 Core insulation (EPS plastic): 16 Stainless steel coupling bracket 0.2 / m2 Lightweight concrete with foam glass chunks and fly ash as aggregates, shrinkage reducing agents and Plastic fibers Thermal conductivity of the entire wall (calculated)

Concrete is generally used according to the European standard (SN) EN 206-1 with the following properties: Compressive strength class: LC12 / 13 or better LC8 / 9 Exposure classes: XC4 XF1 Grösstkornklasse; (all classes): eg Dmax = 8 or Dmax 016, or Dmax = 32 Chloride content class: Cl 0.10 Consistency class: Compaction mass after rolling: at least C2, better C3, or slump: F3, better range F4 to F6, or Slump: S3 better S4 or S5 gross density: D1.4 or D1.2 better D1.0 A cast on site wall, floor or ceiling element is made of a hardenable cement-based casting material, in particular of lightweight concrete. The element has a first wall with a first thickness and a second wall with a second thickness, wherein the thickness of the first wall is significantly greater than the thickness of the second wall. Between the first wall and the second wall, an insulating layer is provided, which is cast over the entire surface in the casting compound. The finished component can be used as exposed concrete part and has a thermal conductivity of <0.16 W / mK.

Legend:

11

wall element

13

first wall

15

second wall

17

damp course

19

reinforcement

21

Spacer means, e.g. 3-dimensional reinforcement structure

23

U-shaped hangers

25

wind anchor

27

Distance holding means on outer formwork wall

29

second spacer between reinforcement and insulation layer

31

plastic anchors

33

Head of the dowel

35

wire

37

connecting pipe

Claims (15)

Cast wall, floor or ceiling element made of a hardenable cement-based casting compound, in particular of lightweight concrete, - A first wall (13) with a first strength and - A second wall (15) having a second thickness, wherein the thickness of the first wall (13) is greater than the thickness of the second wall (15), and a damping layer provided between the first wall (13) and the second wall (15), - One provided in the first wall (13) steel reinforcement with at least a first and a second reinforcement layer, which are dimensionally stable interconnected by means of spacers, and
Coupling straps interconnecting the first wall (13) and the second wall (15),
characterized,.
in that materials with a compressive stress at 10% compression σ ₁₀ ≥ 60 kPa, preferably σ ₁₀ ≥ 150 kPa, and very particularly preferably σ ₁₀ ≥ 300 kPa are used as the insulating layer. Element according to claim 1, characterized in that spacers are provided between the second reinforcing layer and the insulating layer. Element according to claim 1 or 2, characterized in that the casting compound used has a dry bulk density of a maximum of 1500 kg / m3. preferably <1200 Kg / m3 and most preferably <1000 Kg / m3. Element according to one of claims 1 to 3, characterized in that at least the second wall (15) has a reinforcement with fibers, preferably with polymer fibers and advantageously in the form of short cut fibers. Element according to claim 4, characterized in that the proportion of polymer fibers in the second wall (15) between 0.4 to 2.0 Kg / m3, preferably between 0.5 to 1.5 Kg / m3, and most preferably between 0.6 and 1.2 Kg / m3. Element according to claim 4 or 5, characterized in that a highly crystalline polymer, preferably from the group of polyvinyl alcohols, are used as polymer fibers. Element according to one of claims 4 to 6, characterized in that the polymer fibers have a tensile strength> 1,000 N / mm 2, preferably> 1,200 and very particularly preferably> 1,500 N / mm 2 and an E modulus> 30,000 N / mm 2, preferably> 35,000 N / mm 2, and very particularly preferably> 40,000 N / mm 2. Element according to one of claims 1 to 7, characterized in that the insulating layer has a thermal conductivity <0.04 W / mK, preferably <0.035 W / mK and most preferably <0.03 W / mK. Element according to one of claims 1 to 8, characterized in that the insulating layer is made of a plastic or mineral insulation with the exception of polyurethane, preferably substantially of polystyrene, preferably an expanded or extruded polystyrene rigid foam. Element according to one of claims 1 to 9, characterized in that insulation boards are used as an insulating layer with a water vapor diffusion number ≤ ∞, preferably ≤ 250 μ, and most preferably ≤ 50 μ. Element according to one of claims 1 to 10, characterized in that the water absorption capacity of the insulating layer is <4% by volume, preferably <1% by volume and most preferably <0.2% by volume. Element according to one of claims 1 to 11, characterized in that the coupling straps have a U, Z, L, T or similar shape or spiral anchor. Element according to one of claims 1 12, characterized in that 0.2 to 0.4 coupling straps are provided per square meter. Element according to one of claims 1 to 13, characterized in that the cured and dried element has a thermal conductivity <0.16 W / mK. Method for producing a concrete element with the following method steps: - creating a first formwork wall, Attaching a first reinforcing layer of steel at a distance from the first formwork wall, Attaching spacers, preferably in the form of spacer baskets, - attaching a second reinforcing layer of steel on the mentioned spacer means, Arranging an insulating layer with a compressive stress at 10% compression σ ₁₀ ≥ 60 kPa, preferably σ ₁₀ ≥ 150 kPa, and most preferably σ ₁₀ ≥ 300 kPa at a distance from the second reinforcing layer, which insulating layer has an area substantially the same Surface of the first formwork wall corresponds, so that a first formwork space is formed with reinforcement, Introduction of a plurality of coupling straps which extend through the insulating layer and project beyond it by a certain distance on both sides, Creating a second formwork wall, so that a second formwork space without reinforcement is formed between the insulation layer and the second formwork wall, Pouring the shuttering space between the first shuttering wall and the second shuttering wall with a hardenable casting compound, wherein the shuttering spaces are filled with the hardenable casting compound essentially simultaneously or with light flow for the second shuttering space, so that after curing of the casting mass a first wall and a second wall Wall are formed.

Images