Building material or binder, method for production thereof, and use of fiber and slate additives as components of building material or binder

Abstract

The invention relates to a binder which should comprise at least one fibre and a slate additive.

Description

Technical Field

[0001] The invention relates to an adhesive or a building material comprising at least one fiber and slate additive. The invention also relates to a method for producing a building material or an adhesive and to the use of the fiber and slate additive as a component of a building material or an adhesive. Background Art

[0002] Binders and building materials such as concrete are known in the prior art. However, the mechanical strength, resistance to harmful influences and environmental compatibility of such building materials and binders are often problematic with regard to some of the components used in the prior art. Summary of the invention

[0003] The object of the present invention is to eliminate the disadvantages of the prior art.

[0004] Solution to the problem

[0005] The object of the invention is achieved by the subject matter of the independent claims. Advantageous embodiments are described in the dependent claims.

[0006] According to a first exemplary embodiment, the present invention relates to an adhesive comprising at least one fiber and a slate additive. In the context of the present invention, at least one fiber preferably refers to a group, a type or a plurality of fibers, and not, for example, a single spun fiber which is usually only visible under a microscope, nor, for example, a single filament.

[0007] One or more types, varieties or groups of fibers may be considered for use.

[0008] The binder may be, for example, cement or a cement-like mixture, lime or pozzolan. Thus, the binder may be selected from the group comprising cement, lime and pozzolan. In the context of the present invention, pozzolan is preferably understood to mean an artificial or natural rock containing, for example, silicon dioxide, clay, limestone, iron oxide or alkaline substances, and preferably capable of combining with calcium hydroxide and water.

[0009] According to a second exemplary embodiment, the invention relates to a building material comprising at least one binder and a slate additive and at least one fiber.

[0010] The building material may be selected from the group consisting of concrete, mortar and plaster.

[0011] The binder contained in the building material may be selected from the group consisting of cement, lime and pozzolan.Regarding the binder, the above description on the binder according to the first exemplary embodiment of the present invention applies.

[0012] For example, concrete containing cement as a binder can be considered. In addition, concrete containing lime and / or other pozzolans as a binder can be considered.

[0013] Furthermore, mortars containing cement as a binder are conceivable. Also conceivable are mortars containing lime and / or other pozzolans as a binder.

[0014] The same applies to the building material gypsum.

[0015] In addition to the binder, the slate additive and the fibers, the building material may also contain additional materials. Alternatively, the slate additive is used as an additional material and is the only such additional material contained in the building material.

[0016] If the building material contains additional materials in addition to the slate additive, these may be fillers, for example aggregates.

[0017] The building material according to the first exemplary embodiment and the adhesive according to the second exemplary embodiment may comprise at least one fiber, i.e. one fiber, a group of fibers or a plurality of fibers, which may be selected from the group comprising organic natural fibers, inorganic natural fibers, man-made fibers, recycled fibers and wood fibers. The organic natural fibers may be of animal or plant origin.

[0018] Organic natural fibers of animal origin can be, for example, wool, fine animal hair, coarse animal hair or silk. Examples of wool that come into consideration are wool, angora wool, cashmere, etc. Examples of coarse animal hair include horse hair or pig bristles. Examples of silk that come into consideration are mulberry silk or spider silk.

[0019] Organic natural fibers of plant origin may include, for example, seed fibers, bast fibers and hard fibers. Examples of possible seed fibers include cotton or plant silk. Possible bast fibers include, for example, bamboo fibers, hemp fibers, nettle fibers and flax, i.e., linseed fibers. Fibers from reeds, straw or hay may also be considered. According to an exemplary embodiment of the present invention, plant fibers, i.e., organic natural fibers of plant origin, are particularly preferred.

[0020] Particularly preferred plant fibers are hemp fibers, flax fibers and nettle fibers. Therefore, the fiber can be particularly preferably selected from the group comprising hemp fibers, flax fibers and nettle fibers.

[0021] The aforementioned fibers added to adhesives or building materials increase their strength, durability and elasticity in a similar manner to the case of adding steel fibers. However, compared to steel fibers, the aforementioned fibers, in particular organic natural fibers, especially plant fibers, are significantly more environmentally friendly and cheaper to produce and process components made of adhesives or of building materials.

[0022] The building material or adhesive may contain slate additives in the form of grit, sand, gravel or powder.

[0023] In the context of the present invention, slate in the form of grit added as an additive to building materials or adhesives is preferably understood to mean a bulk material made of stones with a diameter between 2 millimeters (mm) and 63 millimeters (mm). Unlike crushed stone, which consists of rounded pebbles, grit usually consists of sharp quarry stones.

[0024] Slate can also be used as an additive in the form of sand, gravel or powder. In the context of the present invention, sand preferably refers to a bulk material made of rock with a particle size of 0.063 mm to 2 mm. Gravel preferably refers to rock with a particle size between 32 and 63 mm. Powder preferably refers to rock with a particle size of less than 0.063 mm.

[0025] The slate additive may be predominantly or completely in the form of unexpanded slate.Expanded slate is a porous and lightweight aggregate which is produced industrially by an expansion process at temperatures around 1200°C.

[0026] In the context of the present invention, a slate additive that is predominantly in the form of unexpanded slate refers to a slate in the form of a bulk material that preferably consists of more than 50%, more preferably more than 70% and even more preferably more than 90% unexpanded slate. A slate additive that is completely in the form of unexpanded slate refers to a bulk material that does not contain expanded slate.

[0027] Slate additives consisting predominantly or completely of unexpanded slate have proven to be advantageous. In particular, unexpanded slate has a reducing effect, i.e. acts as an electron donor. This can have a positive effect on the setting process of the concrete, for example chemical processes such as hydration are positively influenced at the interface between cement and water.

[0028] Even after the building material has solidified, the slate additive, in particular the unexpanded part of the slate, has a positive effect. For example, the building material (e.g. concrete) is more water-resistant, more acid-resistant, more frost-resistant, less reactive with nitrogen compounds, more mechanically stable, less susceptible to mold and bacterial contamination and sulfur formation during aging than without the slate additive. The slate additive also increases the surface density. The reducing properties of the slate additive, which can remain even after solidification, also lead to an oxidation resistance of the components made of the building material, such as concrete walls, etc. On the one hand, this leads to a lower tendency to bacterial contamination, as described above. On the other hand, if the component in question is reinforced concrete, this anti-oxidative (i.e. reducing) property of the slate additive will also have a positive effect, since the steel is more corrosion-resistant due to the slate additive.

[0029] Furthermore, the reducing properties of the slate additive, in particular when sand, powder or grit from unexpanded slate is involved, lead to an advantageous preservation of the added fibers, for example organic natural fibers such as vegetable fibers. Furthermore, the slate additive protects the aforementioned fibers from moisture. In addition to the aforementioned advantages of the slate additive, it can also protect the fibers, thereby extending the durability of the components made of the adhesive or building material, and retain the advantageous properties of the fibers for a longer time even under adverse circumstances.

[0030] The bacteria may optionally be applied to the fibers prior to adding the fibers to the adhesive or building material.

[0031] Bacteria capable of biomineralization are contemplated herein. Generally, mineral-forming bacteria are contemplated, in particular lime-forming bacteria. For example, bacteria of the species Bacillus pasteurianus, Bacillus cohnii or Bacillus pseudofirmus may be used.

[0032] On the one hand, the purpose of applying bacteria to fibers can be to provide the bacteria with a suitable carrier with which the bacteria can be introduced as a component of the building material or adhesive. On the other hand, the fibers can serve as starting material for bacterial metabolic processes. On the one hand, the bacteria can feed on the fibers or multiply on the fibers with the aid of the fibers. On the other hand, the fibers can provide starting material for bacterial metabolic processes, which are considered biomineralization, in which mineral products are formed.

[0033] Bacteria can form these mineral products, such as phosphates or carbonates, from appropriate sources (i.e. starting materials containing phosphorus or calcium sources). These mineral products can fill and therefore repair cracks or defects formed during or after the setting of concrete, i.e. during or after its drying and hardening. It is also possible that at least a portion of bacteria in building materials (e.g. concrete) for example survive or at least keep a metabolic process that can at least achieve biomineralization for a long time, i.e., several years or even decades. These bacteria can be dormant and inactive for several years or even decades. If cracks or similar defects occur in building materials (e.g. concrete), bacteria will become active and utilize appropriate metabolic processes to carry out required biomineralization. For example, the bacteria of the genus Pasteurella, the genus Bacillus and the genus Pseudomonas can be dormant and inactive for decades, and only after contact with air and moisture, i.e., if cracks or defects occur, for example, they become active in building materials such as concrete. The fiber to which bacteria are applied acts as a carrier and donor, i.e., a carrier and food, of the starting material of the bacterial metabolic process.

[0034] Bacteria with the above-mentioned ability to repair any cracks that may occur have been introduced into building materials such as concrete, sometimes referred to as self-healing building materials, such as self-healing concrete.

[0035] The fibers used according to the invention, in particular vegetable fibers, are inexpensive and easy to handle, and the application of the bacteria, as well as the introduction of the fibers mixed with the bacteria into adhesives or into building materials can be simple and inexpensive.

[0036] If cracks etc. form in components made of building materials (e.g. concrete components) as a result of long-term or intense exposure to harmful influences (e.g. frost, chemicals, acids, oxidants or mechanical stress), some slate additives can be used which create an alkaline environment that is favoured by biomineralising bacteria.

[0037] According to an exemplary embodiment of the present invention, a building material, such as concrete, mortar or plaster, may consist of the following components: organic natural fibers, preferably selected from the group comprising hemp fibers, flax fibers and nettle fibers; a binder, selected from the group comprising cement, lime and pozzolan; a slate additive in the form of grit, sand, gravel or powder, which is mainly or completely in the form of unexpanded slate; at least one additional material. According to this exemplary embodiment, the building material contains no steel, no steel fibers, no fungicides, no toxic additives such as accelerators or waterproofing agents.

[0038] In addition to the above adhesive and the above building material, according to an exemplary embodiment, the present invention also includes a method for producing a building material or an adhesive, the method comprising the following steps:

[0039] -Added fiber

[0040] -Add slate additives.

[0041] Regarding the details of the adhesive, building material, fiber and slate additive of the above method, reference is made to the statements of the building material and adhesive according to the above exemplary embodiments.

[0042] As described above with respect to building materials and adhesives, bacteria can also be applied to fibers according to the method of the invention. Preferably, the bacteria are applied to the fibers before they are mixed with the other components of the building material or adhesive.

[0043] If bacteria are used, the fibers can be suspended in the bacterial suspension, mixed with it, sprayed with it, soaked in it or dripped with it. Other variants of applying the bacteria to the fibers are also conceivable.

[0044] It is also conceivable to incubate the fibers before they are added to the building material or adhesive in order to propagate the bacteria. Thus, the fibers can be inoculated with bacteria. This incubation may take several hours or days. Here, an evolutionary selection process of the bacteria can take place before they are added to the building material or adhesive, so that after the building material (e.g. concrete) hardens and dries, these bacteria are present on the fibers in a quantity that is optimal with respect to the properties of the selected fibers as carriers and donors of starting materials for bacterial metabolism.

[0045] The building material or adhesive produced in this way is particularly durable and therefore particularly sustainable. The service life alone greatly increases the sustainability of the building material or adhesive. Furthermore, by using the fibers, in particular if plant fibers or fibers of other natural origin are used, it is possible to dispense with toxic, environmentally harmful and, for example, poorly degradable additives which in the prior art are responsible for increasing the resistance that can be provided by the fibers according to the invention.

[0046] Of course, optionally only one or more types of bacteria can be used for the building material according to the invention, the adhesive according to the invention and the method according to the invention.

[0047] The invention also includes the use of fiber and slate additives as components of building materials or adhesives. The fiber and slate additives are used in combination. For details on building materials or adhesives, fiber and slate additives, reference is made to the above-described adhesives and building materials according to the described exemplary embodiments.

Claims

1. An adhesive comprising at least one fiber and a slate additive.

2. The binder according to claim 1, selected from the group consisting of cement, lime and pozzolan.

3. A building material comprising at least one binder and one slate additive and at least one fiber.

4. The building material according to claim 3, comprising at least one additional material.

5. The building material according to any one of claims 3 or 4, which is selected from the group consisting of concrete, mortar and gypsum.

6. The building material according to any one of claims 3 to 5, wherein The binder is selected from the group consisting of cement, lime and pozzolan.

7. A building material or adhesive according to any one of the preceding claims, wherein The fibers are selected from the group consisting of organic natural fibers, inorganic natural fibers, man-made fibers, recycled fibers, and wood fibers.

8. A building material or adhesive according to any one of the preceding claims, wherein The slate additive is contained in the building material or adhesive in the form of grit, sand, gravel or powder.

9. A building material or adhesive according to any one of the preceding claims, wherein The slate additive is primarily or entirely in the form of unexpanded slate.

10. A method for producing a building material or an adhesive, comprising the steps of: -Added fiber -Add slate additives.

11. Use of fiber and slate additives as components of building materials or adhesives.