FIRE-RESISTANT CONSTRUCTION ELEMENT FOR CONNECTING THERMALLY INSULATED PARTS OF A BUILDING
A construction element is for forming a connection between two parts of a building that are thermally insulated from one another. The element includes an elongate portion having a thermally insulating material, tension bars which run through the thermally insulating portion and which are configured to be anchored in the building parts that are to be connected, and components for absorbing compression and shear forces between the building parts. The construction element has the underside and part of the raised side walls of the elongate portion formed by a fire-resistant profile with a base surface and two raised side walls. A thermally insulating layer is on the base surface of the profile.
The invention is related to a construction element applicable to the construction of buildings, in particular an element for connecting parts of a building that are thermally insulated from one another, e.g. between a concrete floor and a cantilevered floor of a balcony. These elements are also known as ‘thermal breaks’.
PRIOR ARTConnections between internal parts of a building and cantilevered external parts, e.g. a concrete balcony floor need to be realized with a minimal impact on the insulation of the building. For creating this connection, elements are known that consist of an elongate insulating portion provided with reinforcement bars that run through the insulating portion and absorb the tensile forces between the parts of the building that are to be connected. Means are also provided to absorb compression and shear forces. The latter may take the form of compression bars and bars running diagonally through the insulating portion, or of specially formed blocks that are incorporated into the insulating portion. The insulating portion is placed between the parts of the building which are to be connected, whilst the various force-absorbing elements are anchored in said building parts in order to form the connection.
The thermally insulating material used in these elements is, for example, mineral wool such as rock wool or glass wool. Another option is to use synthetic insulating materials, such as PIR, PUR, EPS, XPS, or the like. The latter have better thermal insulation properties than mineral wool and are thus preferred because the desired thermal insulation can be obtained with a lower density of insulation material than would be the case if rock or glass wool are used. On the other hand, materials such as PIR, PUR, and the like have lower fire resistance than the mineral wool variants.
Thus, there is a need for a solution that allows for the use of insulation materials with high thermal insulation properties and that also have good fire safety properties.
SUMMARY OF FEATURES OF THE INVENTIONThe invention concerns a construction element as described in the appended claims.
The invention concerns a construction element for forming a connection between two components of a building that are thermally insulated from one another. The element comprises an elongate portion comprising a thermally insulating material, bars running through the thermally insulating portion in order to absorb tensile forces between the parts of the building, and means to absorb compression and shearing forces between the parts of the building. The construction element according to the invention is characterised in that the underside and part of the raised side walls of the elongate portion is formed by a fire-resistant profile with a undersurface and two raised side walls, and wherein a thermally insulating layer is provided on the base surface of the profile (i.e., between the raised side walls).
The invention thus more specifically concerns a construction element for forming a connection between two components of a building that are thermally insulated from one another, comprising:
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- an elongate portion comprising a thermally insulating material, and configured to be placed between the parts of the building,
- bars which run through the thermally insulating portion and which are configured to be anchored in the building parts that are to be connected, and thus to absorb the tensile forces between these building parts,
- components for absorbing compression and shear forces between the building parts,
characterised in that the underside and part of the raised side walls of the elongate portion are formed by a fire-resistant profile with a base surface and two raised side walls, and wherein a thermally insulating layer is provided on the base surface of the profile (i.e., between the raised side walls). According to a preferred embodiment, the thermally insulating layer is also fire-resistant.
According to one embodiment, the fire-resistant profile is made of a composite material, which may be a fire-resistant fibre cement, preferably having a thickness between 1 and 3 mm. According to an embodiment, the thermally insulating layer is formed of a material with a thermal conductivity lower than 0.06 W/mK at 20° C. The thermally insulating layer may be formed of compressed rock wool.
According to one embodiment, a fire-resistant profile with a base surface and two downward side walls is also provided at the top of the elongate portion, and a thermally insulating and preferably fire-resistant layer is also provided on the base surface of the uppermost profile (i.e., between the downward side walls).
As means to absorb compression and/or shearing forces, a number of support blocks may be provided, wherein the raised side walls of the fire-resistant profile are provided with notches in order to provide space for the supporting blocks.
The thermally insulating material is preferably selected from the group of PIR, PUR, EPS, XPS, and equivalent materials. According to one embodiment, in which the support blocks are used, the thermally insulting material is selected from the group of PIR, PUR, EPS, XPS, and equivalent materials except in the areas above at least one or more of the support blocks, where the thermally insulating material consists of mineral wool, and wherein a tension bar passes through the mineral wool.
In a lower part of the beam-shaped portion 11, support elements 7 are provided to absorb compression and shearing forces. These are support blocks made of a solid material, e.g., concrete, with the shape of the block and the composition of the material provided so as to absorb both compression and shearing forces. In and of itself, this type of block is known, and it is described, e.g., in US 2013/0276393. One or more bars 5 are provided above each of the support blocks 7. As shown in
A construction element according to one possible embodiment of the invention is shown in cross-section in
The fire-resistant profile 15 may also be applied in combination with the compression bars 8 and diagonal bars 9 shown in
The raised walls 17 of the fire-resistant profile 15 are high enough to cover the insulation material 2 laterally up to a certain height. Due to the fire-resistant effect of the fire-resistant profile 15 and the bottom layer 18 beneath the construction element, insulation material 2 with lower-level fire-resistant properties but high thermal insulation properties such as PIR, PUR, EPS, XPS, or equivalents, can be used for the construction element according to the invention. The construction element according to the invention thus offers the advantage that these high-quality materials may be used without compromising fire safety.
The tension bars 5 may be made of steel. According to one embodiment, the tension bars, or at least part of the tension bars, are made of a non-metallic material, e.g., a material based on a resin containing basalt fibres. Other possible materials for the tension bars include materials based on glass fibres or Aramid polymers.
Other embodiments are possible.
In order to test the effective fire resistance of the construction element according to the invention, comparative trials were carried out on elements according to the invention and elements according to the prior art. The tests were performed according to the European standard EN 1365-5:2005. Heating was carried out in accordance with the standard fire curve. The test pieces were heated from below. Four test pieces were tested according to the cross sections shown in
None of the test pieces fulfilled the aforementioned criteria for inadequate fire resistance during the 120 min period. This means that the test pieces according to the invention are as fire-resistant as the known-art test pieces. In other words, the fire-resistant profile 15 and the compressed rock wool layer 18 confer the same fire resistance properties on the element with PIR as an element using rock wool as insulation.
Claims
1. A construction element for forming a connection between two parts of a building which are thermally insulated from one another, the construction element comprising: wherein an underside and part of the raised side walls of the elongate portion are formed by a fire-resistant profile with a base surface and two raised side walls, and wherein a thermally insulating layer is provided on the base surface of the profile.
- an elongate portion comprising a thermally insulating material, and configured to be placed between the parts of the building,
- bars which run through the thermally insulating portion and which are configured to be anchored in the building parts that are to be connected, and to absorb the tensile forces between the building parts,
- components for absorbing compression and shear forces between the building parts,
2. A construction element according to claim 1, wherein the thermally insulating layer is fire-resistant.
3. A construction element according to claim 1, wherein the fire-resistant profile is made of a composite material.
4. A construction element according to claim 3, wherein the composite material is a fire resistant fibre cement.
5. A construction element according to claim 4, wherein the thickness of the profile is between 1 mm and 3 mm.
6. A construction element according to claim 1, wherein the thermally insulating layer is formed of a material with a thermal conductivity lower than 0.06 W/mK at 20° C.
7. A construction element according to claim 1, wherein the thermally insulating layer is made of compressed rock wool.
8. A construction element according to claim 1, comprising an uppermost fire-resistant profile with a base surface and two downward side walls is provided at the top of the elongate portion, and wherein a thermally insulating layer is provided on the base surface of the uppermost profile.
9. A construction element according to claim 8, wherein the thermally insulating layer at the top of the elongate portion is fire-resistant.
10. A construction element according to claim 1, wherein a plurality of support blocks are provided for absorbing compression and/or shearing forces, and wherein the raised side walls of the fire-resistant profile are provided with notches to provide space for the support blocks.
11. A construction element according to claim 1, wherein the thermally insulating material is selected from the group of PIR, PUR, EPS, XPS, and equivalent materials.
12. A construction element according to claim 9, wherein the thermally insulting material is selected from the group of PIR, PUR, EPS, XPS, and equivalent materials except in the areas above at least one or more of the support blocks, where the thermally insulating material consists of mineral wool, and wherein a tension bar passes through the mineral wool.
Type: Application
Filed: Mar 16, 2017
Publication Date: Mar 28, 2019
Inventors: Pierre MICHIELS (Tervuren), Olivier REMY (Brussels)
Application Number: 16/085,907