Building material or binder, method for production thereof, and use of fibers as component of building material or binder

Abstract

The invention relates to an adhesive or a building material, which should comprise at least one fibre, to which bacteria have been applied before the fibre is added to the adhesive.

Description

Technical Field

[0001] The invention relates to an adhesive or building material comprising at least one fiber to which bacteria are applied before the fiber is added to the adhesive or building material. The invention also relates to a method for producing a building material or adhesive and the use of the fiber to which bacteria have been applied as a component of a building material or adhesive. Background Art

[0002] It is known that bacteria are added to adhesives and building materials such as concrete in order to repair possible cracks or the like. The introduction of bacteria into building materials is generally complicated and expensive, as is the production of suitable carrier materials for the bacteria. 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 to which bacteria have been applied before the fiber is added to the adhesive. In the context of the present invention, at least one fiber preferably refers to a group, a class 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] 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.

[0008] According to a second exemplary embodiment, the invention relates to a building material comprising at least one binder and at least one additive and at least one fiber to which bacteria have been applied before the fiber was added to the binder.

[0009] The building material may be selected from concrete, mortar and plaster.

[0010] 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.

[0011] 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.

[0012] Furthermore, mortars containing cement as a binder are conceivable. Also conceivable are mortars containing lime and / or other pozzolans as a binder.

[0013] The same applies to the building material gypsum.

[0014] The additive may be a filler, such as aggregate.

[0015] The building material according to the first exemplary embodiment and the adhesive according to the second exemplary embodiment 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, chemical fibers, recycled fibers and wood fibers. The organic natural fibers may be of animal or plant origin.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] The bacteria used in the building material according to the first exemplary embodiment and the adhesive according to the second exemplary embodiment are capable of biomineralization. Generally speaking, mineral-forming bacteria, in particular lime-forming bacteria, can be considered. For example, bacteria of the species Bacillus pasteurianus, Bacillus cohnii or Bacillus pseudofirmus can be used.

[0020] The fibers improve the properties of the building material or adhesive, for example by increasing its strength, durability and elasticity in a similar way to the case of adding steel fibers. However, compared to steel fibers, the above fibers, in particular organic natural fibers, especially vegetable fibers, are significantly more environmentally friendly and cheaper to produce and process components made of adhesives or of building materials.

[0021] On the one hand, the purpose of applying the bacteria to the fibers can be to provide a suitable carrier for the bacteria, with which the bacteria can be introduced as a component of the building material or adhesive into the building material or adhesive.

[0022] On the other hand, fibers can serve as starting materials for bacterial metabolic processes. On the one hand, bacteria can feed on fibers or multiply on fibers with the help of fibers. On the other hand, fibers can provide starting materials for bacterial metabolic processes, which are considered biomineralization, in which mineral products are formed.

[0023] 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 Bacillus pseudofirmus may be dormant and inactive for decades, and only after contact with air and moisture, i.e., if cracks or defects occur, for example, in building materials (e.g., components made of concrete), they become active. The fiber applied with bacteria according to the present invention acts as a carrier and donor of the starting materials of the bacterial metabolic process, i.e., living space and food.

[0024] 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.

[0025] The fibers used according to the invention, in particular vegetable fibers, are inexpensive, easy to handle, and the application of the bacteria as described in more detail below, and the introduction of the fibers mixed with the bacteria into adhesives or into building materials can be simple and inexpensive.

[0026] According to the above exemplary embodiments, slate can be added as an additive to an adhesive or a building material. Preferably, the slate additive can be used in the form of coarse sand, gravel, sand or powder.

[0027] If the component made of the building material, for example a concrete component such as a wall, etc., remains substantially intact, the slate additive ensures that the fibers are preserved and protected from moisture. According to an exemplary embodiment of the invention, the concrete component produced in this way is less susceptible to harmful influences, such as oxidants, water, acids, frost and mechanical stress. For example, if cracks or the like are formed due to long-term or intense exposure to such or other harmful influences, the slate additive can provide an alkaline environment, which is preferred by some bacteria capable of biomineralization.

[0028] According to an exemplary embodiment of the 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; at least one additive; wherein before the fibers are added to the building material, bacteria capable of biomineralization are applied to the fibers, in particular bacteria of the species Pasteurella, Bacillus cohnii or Bacillus pseudofirmus. According to this exemplary embodiment, the building material contains no steel, no steel fibers, no bactericides, no toxic additives such as accelerators or waterproofing agents.

[0029] 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:

[0030] - applying bacteria to the fibers;

[0031] - mixing the fibers with the binder or at least one other component of the building material.

[0032] Regarding the details of the adhesive, building material, fiber, and bacteria of the above-mentioned method, reference is made to the statements of the building material and adhesive according to the above-mentioned exemplary embodiments.

[0033] The bacteria are preferably applied to the fibers before the fibers are mixed with the other components of the building material or adhesive.

[0034] For example, 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.

[0035] 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.

[0036] 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.

[0037] Of course, one or several types of bacteria may be used for the building material according to the invention, the adhesive according to the invention and the method according to the invention.In addition, one or more types, varieties or groups of fibers may be used.

[0038] The present invention also includes the use of fibers to which bacteria have been applied as a component of a building material or adhesive. Regarding the details of the building material or adhesive, the fibers and the bacteria, 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 to which bacteria have been applied before the fiber is added to the adhesive.

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 at least one additive and at least one fiber to which bacteria have been applied before the fiber is added to the binder.

4. The building material according to claim 3, wherein the building material is selected from the group consisting of concrete, mortar and gypsum.

5. The building material according to any one of claims 3 or 4, wherein The binder is selected from the group consisting of cement, lime and pozzolan.

6. A building material or adhesive according to any one of the preceding claims, wherein The fiber is selected from the group consisting of organic natural fiber, inorganic natural fiber, chemical fiber, regenerated fiber, wood fiber.

7. A building material or adhesive according to any one of the preceding claims, wherein The bacteria are capable of biomineralization.

8. A building material or adhesive as claimed in any preceding claim to which a slate additive has been added.

9. A method for producing a building material or an adhesive, comprising the steps of: - applying bacteria to the fibers; - mixing the fibers with the binder or at least one other component of the building material.

10. Use of fibers to which bacteria have been applied as a component of a building material or adhesive.