A fiber-reinforced crack-resistant foamed concrete board and its preparation method

Abstract

This invention relates to a fiber-reinforced crack-resistant foamed concrete board and its preparation method, belonging to the field of building materials technology. The foamed concrete board comprises the following components in parts by weight: 500-800 parts cement, 180-300 parts water, 4-8 parts alkali-resistant glass fiber, 3-6 parts ceramic fiber, 3-6 parts basalt fiber, 100-200 parts recycled micro powder, 100-150 parts red brick powder, 100-250 parts diatomaceous earth, 20-40 parts nano-foam, 30-80 parts activator, 2-6 parts silane coupling agent, 1-3 parts shrinkage reducer, 2-6 parts expansion agent, 0.1-0.2 parts hydroxypropyl methylcellulose, 20-50 parts SAP resin, and 40-100 parts ceramsite. The foamed concrete prepared by this invention overcomes the shortcomings of existing foamed concrete technologies, such as low strength, poor crack resistance, and low economic efficiency, and has good market prospects.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, and in particular to a fiber-reinforced crack-resistant foamed concrete board and its preparation method. Background Technology

[0002] Foamed concrete boards are a lightweight, porous, new type of building wall material made from cement, foaming agent, and water. The mixture is stirred, poured into molds, and then cured. It possesses excellent properties such as thermal insulation, sound insulation, fire resistance, waterproofing, and moisture resistance. It is suitable not only for newly constructed brick-concrete or frame structures and renovation projects of existing buildings, but also particularly for interior partitions and floor slabs in various industrial plants and residential buildings.

[0003] Currently, commonly used methods for preparing foamed concrete boards include physical foaming and chemical foaming. The physical foaming method involves first diluting the foaming agent and mixing it with air to create foam, which is then mixed with prepared concrete slurry to form a foamed concrete slurry. Finally, the slurry is poured, solidified, and cured. However, the physical foaming method has drawbacks, including complex equipment, difficulty in construction on the floors and roofs of high-rise buildings, and uneven foam pore size.

[0004] The use of chemical foaming to prepare foamed concrete boards has gradually become more widely used, but it has disadvantages such as low strength and easy cracking. Summary of the Invention

[0005] (a) Technical problems to be solved

[0006] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a fiber-reinforced crack-resistant foamed concrete board and its preparation method, which solves the technical problems of low strength and easy cracking in the preparation of foamed concrete boards by chemical foaming method.

[0007] (II) Technical Solution

[0008] To achieve the above objectives, the main technical solutions adopted by the present invention include:

[0009] In a first aspect, the present invention provides a fiber-reinforced crack-resistant foamed concrete board, which is made of the following components in parts by weight: 500-800 parts cement, 180-300 parts water, 4-8 parts alkali-resistant glass fiber, 3-6 parts ceramic fiber, 3-6 parts basalt fiber, 100-200 parts recycled micro powder, 100-150 parts red brick powder, 100-250 parts diatomaceous earth, 20-40 parts nano foam, 30-80 parts activator, 2-6 parts silane coupling agent, 1-3 parts shrinkage reducer, 2-6 parts expansion agent, 0.1-0.2 parts hydroxypropyl methylcellulose, 20-50 parts SAP resin, and 40-100 parts ceramsite.

[0010] Optionally, the foamed concrete board is provided with alkali-resistant glass fiber mesh on both sides; the mesh size of the alkali-resistant glass fiber mesh is 10-20mm.

[0011] The dimensions of the alkali-resistant glass fiber mesh are determined based on the dimensions of the foam board.

[0012] Optionally, the cement is one of silicate cement, aluminate cement, or sulfoaluminate cement.

[0013] Preferably, the cement is ordinary silicate 42.5 cement.

[0014] Optionally, the alkali-resistant glass fiber has a diameter of 10-20 μm and a length of 12-20 mm; the ceramic fiber has a diameter of 150-250 μm and a length of 9-12 mm; and the basalt fiber has a diameter of 15-18 μm and a length of 15-20 mm.

[0015] The alkali-resistant glass fiber, ceramic fiber, and basalt fiber of the present invention are prone to agglomeration and unevenness if they are too thick or too long, thereby reducing the reinforcing effect of the fiber.

[0016] Optionally, the recycled micro powder is micro powder produced by crushing waste concrete (the main component is cement mortar), the particle size of the recycled micro powder is 0.075-0.15mm, the particle size of the red brick powder is 0.075-0.15mm, and the SiO2 content of the diatomaceous earth is greater than 95wt%.

[0017] The recycled micro powder and red brick powder of this invention are solid wastes. Adding them reduces emissions on the one hand, and the active substances they contain help improve the strength of concrete on the other hand. The added diatomaceous earth is also an active substance, which helps improve the later strength of concrete.

[0018] Optionally, the activator is one or more of sodium sulfate, sodium carbonate, or sodium silicate.

[0019] Optionally, the silane coupling agent is a vinyl silane coupling agent; the shrinkage reducing agent is an amino alcohol shrinkage reducing agent, the main component of which is 2-amino-2-methyl-1-propanol; the expanding agent is a calcium carbonate-lime composite expanding agent; the SAP resin is a polyacrylic acid superabsorbent resin with a particle size of 150-200 mesh; and the ceramsite has a particle size of 5-15 mm. The hydroxypropyl methylcellulose is a white powder.

[0020] Optionally, the nanofoam is formed by physical foaming of a nanofoaming agent.

[0021] Secondly, the present invention provides a method for preparing the foamed concrete board, comprising the following steps:

[0022] S1. Arrange alkali-resistant glass fiber mesh in the mold for preparing foamed concrete board;

[0023] S2. Soak SAP resin and ceramsite in water for 2-4 hours to absorb water.

[0024] S3. After mixing cement, alkali-resistant glass fiber, ceramic fiber and basalt fiber evenly, add silane coupling agent and continue mixing evenly to obtain fiber mixture;

[0025] S4. Mix the recycled micro powder, red brick powder and diatomaceous earth, stir evenly, then add the activator and continue stirring evenly.

[0026] S5. Mix the cement, shrinkage reducer, expansion agent, and hydroxypropyl methylcellulose and stir until homogeneous;

[0027] S6. Add the mixture prepared in steps S2, S3 and S4 to the mixture obtained in step S5, stir evenly, and then add water and stir.

[0028] S7. Add nano foam to the mixture obtained in step S6, stir, and then quickly transfer it to the mold in step S1, cure, and demold to obtain the final product.

[0029] Optionally, in steps S3, S4 and S5, the stirring time is 60-120s; in step S6, the stirring time is 60-120s, and after adding water, the stirring time is 120-180s; in step S7, the stirring time is 90-120s.

[0030] Optionally, in step S7, the curing time is 7-10 days.

[0031] (III) Beneficial Effects

[0032] The beneficial effects of this invention are as follows: This invention utilizes recycled micro-powder, red brick powder, and diatomaceous earth to replace cement, which not only facilitates the reuse of solid waste, reduces the cost of solid waste treatment and its environmental burden, and promotes the resource utilization of solid waste, but also significantly reduces the material costs of construction. Furthermore, it saves a large amount of cement resources, alleviates the resource consumption phenomenon of calcining cement, and achieves resource recycling. Simultaneously, the recycled micro-powder and red brick powder contain a large amount of SiO2, Al2O3, Fe2O3, and CaO. By using an activator to stimulate their activity, they can react to generate hydrated calcium silicate, hydrated calcium aluminate, hydrated calcium aluminoferrite, and ettringite, filling the pores of foamed concrete. The recycled micro-powder, red brick powder, and diatomaceous earth have a synergistic effect, significantly improving the strength of foamed concrete.

[0033] This invention utilizes silane coupling agents to modify alkali-resistant glass fibers, ceramic fibers, and basalt fibers. The silane coupling agent reduces the contact angle of the fiber surface, thereby improving its wettability and making it easier for cement-based materials to bond with the fibers. Simultaneously, the silane coupling agent can form a layer of tiny particles on the fiber surface, increasing surface roughness and thus improving its mechanical anchoring force and chemical bonding strength. Furthermore, all three types of fibers are inorganic fibers, allowing them to bond well together and leverage their synergistic properties to better improve the bonding performance of the foamed concrete board. The fiber bridging effect also enhances the connection between the internal structures of the foamed concrete, reducing its drying shrinkage and improving its crack resistance. In addition, all three fibers possess good durability and fire resistance, making this foamed concrete suitable for various complex environments.

[0034] Furthermore, this invention incorporates SAP resin and ceramsite into the foamed concrete. SAP resin and ceramsite possess exceptional water absorption capabilities. On one hand, they provide a skeletal structure to the foamed concrete, enhancing its strength. On the other hand, during the curing process, under a humidity gradient, SAP resin and ceramsite release moisture, effectively providing internal curing and reducing drying shrinkage, thus improving the foamed concrete's crack resistance. SAP resin has relatively poor mechanical properties, while ceramsite is more robust and can serve as the skeleton of the foamed concrete. Because foam boards exhibit significant drying shrinkage, using ceramsite alone has a limited effect on mitigating drying shrinkage. However, the combination of SAP resin and ceramsite significantly reduces the drying shrinkage of the foamed concrete.

[0035] Meanwhile, this invention incorporates various shrinkage-reducing agents, expansion agents, and water-retaining agents into foamed concrete, which improves its workability and crack resistance. The foamed concrete produced by this invention overcomes the shortcomings of existing foamed concrete on the market, such as low strength, poor crack resistance, and low economic efficiency, and has promising market prospects. Detailed Implementation

[0036] To better explain and facilitate understanding of the present invention, the present invention will be described in detail below through specific embodiments.

[0037] To better understand the above technical solutions, exemplary embodiments of the present invention will be described in more detail below. It should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the invention to those skilled in the art.

[0038] Example 1

[0039] A method for preparing a fiber-reinforced crack-resistant foamed concrete board includes the following steps:

[0040] Step 1: Prepare materials according to the following weight proportions: per cubic meter of ordinary silicate 42.5 cement: 600 parts, water: 200 parts, 2 sheets of alkali-resistant glass fiber mesh with a mesh size of 10mm (the mesh size is the same as the size of the foamed concrete board to be prepared), 6 parts of alkali-resistant glass fiber (diameter 10μm, length 12mm), 4 parts of ceramic fiber (diameter 150μm, length 9mm), 4 parts of basalt fiber (diameter 15μm, length 15mm), 150 parts of recycled micro powder (particle size 0.075mm), red brick. 100 parts powder (0.075 mm particle size), 150 parts diatomaceous earth (SiO2 content greater than 95 wt%), 30 parts nano foam (nano particles prepared from nano titanium dioxide particles through physical foaming), 40 parts sodium sulfate activator, 3 parts vinyl silane coupling agent, 2 parts 2-amino-2-methyl-1-propanol shrinkage reducer, 3 parts calcium carbonate-lime composite expansion agent, 0.15 parts hydroxypropyl methylcellulose, 30 parts SAP resin (polyacrylic acid superabsorbent resin, 150 mm particle size), and 50 parts ceramsite (5 mm particle size).

[0041] Step 2: Prepare a mold for the foamed concrete board. The mold should be 2400mm long, 600mm wide, and 100mm high. Place the alkali-resistant fiberglass mesh in the mold.

[0042] Step 3: Soak the SAP resin and ceramsite in water for 2 hours to absorb water.

[0043] Step 4: Mix alkali-resistant glass fiber, ceramic fiber and basalt fiber, stir for 60 seconds, add silane coupling agent after stirring evenly, and continue stirring for 120 seconds to obtain fiber mixture, pour into container and set aside for later use.

[0044] Step 5: Add the recycled micro powder, red brick powder and diatomaceous earth to the mixer and stir for 60 seconds. After stirring evenly, add sodium sulfate activator and continue stirring for 120 seconds.

[0045] Step 6: Add ordinary silicate 42.5 cement, shrinkage reducer, expansion agent, and hydroxypropyl methylcellulose to the mixer and mix for 60 seconds. After mixing evenly, add water and continue mixing for 120 seconds.

[0046] Step 7: Add the mixture prepared in Steps 3, 4 and 5 to the mixture obtained in Step 6, stir for 120 seconds, and then add water and stir.

[0047] Step 8: Finally, add nano foam to the mixer, stir again for 120 seconds, then quickly transfer it out of the mixer and place it in a mold with alkali-resistant glass fiber mesh. After 24 hours, it will reach its strength. After curing for 7 days, it will be demolded after molding to obtain fiber-reinforced crack-resistant foam concrete board.

[0048] According to the dry density test conducted in accordance with JG / T 266-2011 "Foamed Concrete", the dry density of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 800 kg / m³. 3 .

[0049] The compressive strength test was conducted according to JG / T 266-2011 "Foamed Concrete". The 7-day compressive strength of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 7.5 MPa.

[0050] Example 2

[0051] A method for preparing a fiber-reinforced crack-resistant foamed concrete board includes the following steps:

[0052] Step 1: Prepare materials according to the following weight proportions: per cubic meter of ordinary silicate 42.5 cement, 640 parts, water, 210 parts, 2 sheets of alkali-resistant glass fiber mesh with a mesh size of 20mm (the mesh size is the same as the size of the foamed concrete board to be prepared), 6 parts of alkali-resistant glass fiber (diameter 20μm, length 20mm), 4 parts of ceramic fiber (diameter 250μm, length 12mm), 4 parts of basalt fiber (diameter 18μm, length 20mm), and 130 parts of recycled micro powder (particle size 0.15mm). 90 parts red brick powder (0.15 mm particle size), 160 parts diatomaceous earth (SiO2 content greater than 95 wt%), 25 parts nano foam (nanoparticles prepared from nano titanium dioxide particles through physical foaming), 40 parts sodium carbonate activator, 3 parts silane coupling agent, 2 parts 2-amino-2-methyl-1-propanol shrinkage reducer, 3 parts calcium carbonate-lime composite expansion agent, 0.15 parts hydroxypropyl methylcellulose, 30 parts SAP resin (polyacrylic acid superabsorbent resin, 200 mm particle size), and 40 parts ceramsite (15 mm particle size).

[0053] Step 2: Prepare a mold for the foamed concrete board. The mold should be 2400mm long, 600mm wide, and 100mm high. Place the alkali-resistant fiberglass mesh in the mold.

[0054] Step 3: Soak the SAP resin and ceramsite in water for 2 hours to absorb water.

[0055] Step 4: Mix alkali-resistant glass fiber, ceramic fiber and basalt fiber, stir for 60 seconds, add silane coupling agent after stirring evenly, and continue stirring for 120 seconds to obtain fiber mixture, pour into container and set aside for later use.

[0056] Step 5: Add the recycled micro powder, red brick powder and diatomaceous earth to the mixer and stir for 60 seconds. After stirring evenly, add sodium sulfate activator and continue stirring for 120 seconds.

[0057] Step 6: Add ordinary silicate 42.5 cement, shrinkage reducer, expansion agent, and hydroxypropyl methylcellulose to the mixer and mix for 60 seconds. After mixing evenly, add water and continue mixing for 120 seconds.

[0058] Step 7: Add the mixture prepared in Steps 3, 4 and 5 to the mixture obtained in Step 6, stir for 120 seconds, and then add water and stir.

[0059] Step 8: Finally, add nano foam to the mixer, stir again for 120 seconds, then quickly transfer it out of the mixer and place it in a mold with alkali-resistant glass fiber mesh. After 24 hours, it will reach its strength. After curing for 7 days, it will be demolded after molding to obtain fiber-reinforced crack-resistant foam concrete board.

[0060] According to the dry density test conducted in accordance with JG / T 266-2011 "Foamed Concrete", the dry density of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 1000 kg / m³. 3 .

[0061] The compressive strength test was conducted according to JG / T 266-2011 "Foamed Concrete". The 7-day compressive strength of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 12.5 MPa.

[0062] Example 3

[0063] Step 1: Prepare materials according to the following weight proportions: per cubic meter of ordinary silicate 42.5 cement: 750 parts, water: 220 parts, 2 sheets of alkali-resistant glass fiber mesh with a mesh size of 10nm (the mesh size is the same as the size of the foamed concrete board to be prepared), 6 parts of alkali-resistant glass fiber (diameter 15μm, length 15mm), 6 parts of ceramic fiber (diameter 200μm, length 11mm), 6 parts of basalt fiber (diameter 16μm, length 17mm), and 150 parts of recycled micro powder (particle size 0.1mm). 60 parts red brick powder (0.1 mm particle size), 180 parts diatomaceous earth (SiO2 content greater than 95 wt%), 22 parts nano foam (nanoparticles prepared from nano titanium dioxide particles through physical foaming), 40 parts sodium silicate activator, 3 parts silane coupling agent, 2 parts 2-amino-2-methyl-1-propanol shrinkage reducer, 3 parts calcium carbonate-lime composite expansion agent, 0.15 parts hydroxypropyl methylcellulose, 20 parts SAP resin (polyacrylic acid superabsorbent resin, 170 mm particle size), and 40 parts ceramsite (10 mm particle size).

[0064] Step 2: Prepare a mold for the foamed concrete board. The mold should be 2400mm long, 600mm wide, and 100mm high. Place the alkali-resistant fiberglass mesh in the mold.

[0065] Step 3: Soak the SAP resin and ceramsite in water for 2 hours to absorb water.

[0066] Step 4: Mix alkali-resistant glass fiber, ceramic fiber and basalt fiber, stir for 60 seconds, add silane coupling agent after stirring evenly, and continue stirring for 120 seconds to obtain fiber mixture, pour into container and set aside for later use.

[0067] Step 5: Add the recycled micro powder, red brick powder and diatomaceous earth to the mixer and stir for 60 seconds. After stirring evenly, add sodium sulfate activator and continue stirring for 120 seconds.

[0068] Step 6: Add ordinary silicate 42.5 cement, shrinkage reducer, expansion agent, and hydroxypropyl methylcellulose to the mixer and mix for 60 seconds. After mixing evenly, add water and continue mixing for 120 seconds.

[0069] Step 7: Add the mixture prepared in Steps 3, 4 and 5 to the mixture obtained in Step 6, stir for 120 seconds, and then add water and stir.

[0070] Step 8: Finally, add nano foam to the mixer, stir again for 120 seconds, then quickly transfer it out of the mixer and place it in a mold with alkali-resistant glass fiber mesh. After 24 hours, it will reach its strength. After curing for 7 days, it will be demolded after molding to obtain fiber-reinforced crack-resistant foam concrete board.

[0071] According to the dry density test conducted in accordance with JG / T 266-2011 "Foamed Concrete", the dry density of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 1200 kg / m³. 3 .

[0072] The compressive strength test was conducted according to JG / T 266-2011 "Foamed Concrete". The 7-day compressive strength of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 16.6 MPa.

[0073] Example 4

[0074] A method for preparing a fiber-reinforced crack-resistant foamed concrete board includes the following steps:

[0075] Step 1: Prepare materials according to the following weight proportions: 500 parts ordinary silicate 42.5 cement, 180 parts water, 2 sheets of alkali-resistant glass fiber mesh with a mesh size of 10mm (the mesh size is the same as the size of the foamed concrete board to be prepared), 4 parts alkali-resistant glass fiber (diameter 10μm, length 12mm), 3 parts ceramic fiber (diameter 150μm, length 9mm), 3 parts basalt fiber (diameter 15μm, length 15mm), and 100 parts recycled micro powder (particle size 0.075mm). 100 parts red brick powder (particle size 0.075mm), 100 parts diatomaceous earth (SiO2 content greater than 95wt%), 20 parts nano foam (nanoparticles prepared from nano titanium dioxide particles through physical foaming), 30 parts sodium sulfate activator, 2 parts silane coupling agent, 1 part 2-amino-2-methyl-1-propanol shrinkage reducer, 2 parts calcium carbonate-lime composite expansion agent, 0.1 parts hydroxypropyl methylcellulose, 20 parts SAP resin (polyacrylic acid superabsorbent resin, particle size 150mm), and 40 parts ceramsite (particle size 5mm).

[0076] Step 2: Prepare a mold for the foamed concrete board. The mold should be 2400mm long, 600mm wide, and 100mm high. Place the alkali-resistant fiberglass mesh in the mold.

[0077] Step 3: Soak the SAP resin and ceramsite in water for 2 hours to absorb water.

[0078] Step 4: Mix alkali-resistant glass fiber, ceramic fiber and basalt fiber, stir for 60 seconds, add silane coupling agent after stirring evenly, and continue stirring for 120 seconds to obtain fiber mixture, pour into container and set aside for later use.

[0079] Step 5: Add the recycled micro powder, red brick powder and diatomaceous earth to the mixer and stir for 60 seconds. After stirring evenly, add sodium sulfate activator and continue stirring for 120 seconds.

[0080] Step 6: Add ordinary silicate 42.5 cement, shrinkage reducer, expansion agent, and hydroxypropyl methylcellulose to the mixer and mix for 60 seconds. After mixing evenly, add water and continue mixing for 120 seconds.

[0081] Step 7: Add the mixture prepared in Steps 3, 4 and 5 to the mixture obtained in Step 6, stir for 120 seconds, and then add water and stir.

[0082] Step 8: Finally, add nano foam to the mixer, stir again for 120 seconds, then quickly transfer it out of the mixer and place it in a mold with alkali-resistant glass fiber mesh. After 24 hours, it will reach its strength. After curing for 7 days, it will be demolded after molding to obtain fiber-reinforced crack-resistant foam concrete board.

[0083] According to the dry density test conducted in accordance with JG / T 266-2011 "Foamed Concrete", the dry density of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 1300 kg / m³. 3 .

[0084] The compressive strength test was conducted according to JG / T 266-2011 "Foamed Concrete". The 7-day compressive strength of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 19.5 MPa.

[0085] Example 5

[0086] A method for preparing a fiber-reinforced crack-resistant foamed concrete board includes the following steps:

[0087] Step 1: Prepare materials according to the following weight proportions: 800 parts of ordinary silicate 42.5 cement, 300 parts of water, 2 sheets of alkali-resistant glass fiber mesh with a mesh size of 10mm (the mesh size is the same as the size of the foamed concrete board to be prepared), 8 parts of alkali-resistant glass fiber (diameter 10μm, length 12mm), 6 parts of ceramic fiber (diameter 150μm, length 9mm), 6 parts of basalt fiber (diameter 15μm, length 15mm), and 200 parts of recycled micro powder (particle size 0.075mm). 150 parts red brick powder (particle size 0.075mm), 250 parts diatomaceous earth (SiO2 content greater than 95wt%), 40 parts nano foam (nanoparticles prepared from nano titanium dioxide particles through physical foaming), 80 parts sodium sulfate activator, 6 parts silane coupling agent, 3 parts 2-amino-2-methyl-1-propanol shrinkage reducer, 6 parts calcium carbonate-lime composite expansion agent, 0.2 parts hydroxypropyl methylcellulose, 50 parts SAP resin (polyacrylic acid superabsorbent resin, particle size 150mm), and 10 parts ceramsite (particle size 5mm).

[0088] Step 2: Prepare a mold for the foamed concrete board. The mold should be 2400mm long, 600mm wide, and 100mm high. Place the alkali-resistant fiberglass mesh in the mold.

[0089] Step 3: Soak the SAP resin and ceramsite in water for 2 hours to absorb water.

[0090] Step 4: Mix alkali-resistant glass fiber, ceramic fiber and basalt fiber, stir for 60 seconds, add silane coupling agent after stirring evenly, and continue stirring for 120 seconds to obtain fiber mixture, pour into container and set aside for later use.

[0091] Step 5: Add the recycled micro powder, red brick powder and diatomaceous earth to the mixer and stir for 60 seconds. After stirring evenly, add sodium sulfate activator and continue stirring for 120 seconds.

[0092] Step 6: Add ordinary silicate 42.5 cement, shrinkage reducer, expansion agent, and hydroxypropyl methylcellulose to the mixer and mix for 60 seconds. After mixing evenly, add water and continue mixing for 120 seconds.

[0093] Step 7: Add the mixture prepared in Steps 3, 4 and 5 to the mixture obtained in Step 6, stir for 120 seconds, and then add water and stir.

[0094] Step 8: Finally, add nano foam to the mixer, stir again for 120 seconds, then quickly transfer it out of the mixer and place it in a mold with alkali-resistant glass fiber mesh. After 24 hours, it will reach its strength. After curing for 7 days, it will be demolded after molding to obtain fiber-reinforced crack-resistant foam concrete board.

[0095] According to the dry density test conducted in accordance with JG / T 266-2011 "Foamed Concrete", the dry density of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 1500 kg / m³. 3 .

[0096] The compressive strength test was conducted according to JG / T 266-2011 "Foamed Concrete". The 7-day compressive strength of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 21.3 MPa.

[0097] Comparative Example 1

[0098] This comparative example provides a method for preparing foamed concrete boards. The specific method is the same as in Example 1, except that diatomaceous earth is not used as the raw material. Step 5 of this comparative example is as follows: add the recycled micro powder and red brick powder to the mixer, stir for 60 seconds, add sodium sulfate activator after stirring evenly, and continue stirring for 120 seconds.

[0099] According to the dry density test conducted in accordance with JG / T 266-2011 "Foamed Concrete", the dry density of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 750 kg / m³. 3 .

[0100] The compressive strength test was conducted according to JG / T 266-2011 "Foamed Concrete". The 7-day compressive strength of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 4.2 MPa.

[0101] Comparative Example 2

[0102] This comparative example provides a method for preparing foamed concrete boards. The specific method is the same as in Example 1, except that red brick powder is not used as the raw material. Step 5 of this comparative example is as follows: add the recycled micro powder and diatomaceous earth into a mixer, stir for 60 seconds, add sodium sulfate activator after stirring evenly, and continue stirring for 120 seconds.

[0103] According to the dry density test conducted in accordance with JG / T 266-2011 "Foamed Concrete", the dry density of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 770 kg / m³. 3 .

[0104] The compressive strength test was conducted according to JG / T 266-2011 "Foamed Concrete". The 7-day compressive strength of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 5.1 MPa.

[0105] Comparative Example 3

[0106] This comparative example provides a method for preparing foamed concrete boards. The specific method is the same as in Example 1, except that recycled micro powder is not used as the raw material. Step 5 of this comparative example is as follows: add red brick powder and diatomaceous earth into a mixer, stir for 60 seconds, add sodium sulfate activator after stirring evenly, and continue stirring for 120 seconds.

[0107] According to the dry density test conducted in accordance with JG / T 266-2011 "Foamed Concrete", the dry density of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 760 kg / m³. 3 .

[0108] The compressive strength test was conducted according to JG / T 266-2011 "Foamed Concrete". The 7-day compressive strength of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 5.9 MPa.

[0109] Comparative Example 4

[0110] This comparative example provides a method for preparing foamed concrete boards. The specific method is the same as in Example 1, except that no activator is used in the raw materials. Step 5 of this comparative example is: adding recycled micro powder, red brick powder and diatomaceous earth into a mixer and stirring for 60 seconds.

[0111] According to the dry density test conducted in accordance with JG / T 266-2011 "Foamed Concrete", the dry density of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 800 kg / m³. 3 .

[0112] The compressive strength test was conducted according to JG / T 266-2011 "Foamed Concrete". The 7-day compressive strength of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 5.5 MPa.

[0113] The data from Comparative Examples 1-3 above demonstrate that selecting any two of the recycled micro powder, red brick powder, and diatomaceous earth does not significantly improve the strength of the prepared foamed concrete panels. Although Comparative Example 4 used recycled micro powder, red brick powder, and diatomaceous earth simultaneously, the lack of an activator prevented the production of hydration products such as hydrated calcium silicate, hydrated calcium aluminate, hydrated calcium aluminoferrite, and ettringite, resulting in a poor strength improvement effect on the foamed concrete panels.

[0114] Comparative Example 5

[0115] This comparative example provides a method for preparing foamed concrete boards. The specific method is the same as in Example 1, except that basalt fiber is not used as the raw material. Step 4 of this comparative example is as follows: alkali-resistant glass fiber and ceramic fiber are mixed and stirred for 60 seconds. After stirring evenly, a silane coupling agent is added and stirring is continued for 120 seconds to obtain a fiber mixture, which is then poured into a container and left to be used.

[0116] According to the dry density test conducted in accordance with JG / T 266-2011 "Foamed Concrete", the dry density of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 750 kg / m³. 3 .

[0117] The compressive strength test was conducted according to JG / T 266-2011 "Foamed Concrete". The 7-day compressive strength of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 5.7 MPa.

[0118] Comparative Example 6

[0119] This comparative example provides a method for preparing foamed concrete boards. The specific method is the same as in Example 1, except that ceramic fibers are not used as raw materials. Step 4 of this comparative example is as follows: alkali-resistant glass fibers and basalt fibers are mixed and stirred for 60 seconds. After stirring evenly, a silane coupling agent is added and stirring is continued for 120 seconds to obtain a fiber mixture. The mixture is then poured into a container and left to stand for later use.

[0120] According to the dry density test conducted in accordance with JG / T 266-2011 "Foamed Concrete", the dry density of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 770 kg / m³. 3 .

[0121] The compressive strength test was conducted according to JG / T 266-2011 "Foamed Concrete". The 7-day compressive strength of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 5.1 MPa.

[0122] Comparative Example 7

[0123] This comparative example provides a method for preparing foamed concrete boards. The specific method is the same as in Example 1, except that alkali-resistant glass fiber is not used as the raw material. Step 4 of this comparative example is as follows: ceramic fiber and basalt fiber are mixed and stirred for 60 seconds. After stirring evenly, silane coupling agent is added and stirring is continued for 120 seconds to obtain a fiber mixture, which is then poured into a container and left to be used.

[0124] According to the dry density test conducted in accordance with JG / T 266-2011 "Foamed Concrete", the dry density of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 800 kg / m³. 3 .

[0125] The compressive strength test was conducted according to JG / T 266-2011 "Foamed Concrete". The 7-day compressive strength of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 5.5 MPa.

[0126] The data from Comparative Examples 5-7 above demonstrate that selecting any two of alkali-resistant glass fibers, ceramic fibers, and basalt fibers does not significantly improve the crack resistance of the prepared foamed concrete panels. In this invention, the three fibers have a synergistic effect; when used together, they bond well together, forming fiber bridging, which enhances the connection between the internal structures of the foamed concrete and improves its crack resistance.

[0127] Comparative Example 8

[0128] This comparative example provides a method for preparing foamed concrete boards. The specific method is the same as in Example 1, except that SAP resin is not used as the raw material. Step 3 of this comparative example involves immersing the expanded clay aggregate in water for 2 hours.

[0129] According to the dry density test conducted in accordance with JG / T 266-2011 "Foamed Concrete", the dry density of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 780 kg / m³. 3 .

[0130] The compressive strength test was conducted according to JG / T 266-2011 "Foamed Concrete". The 7-day compressive strength of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 5.8 MPa.

[0131] Comparative Example 9

[0132] This comparative example provides a method for preparing foamed concrete boards. The specific method is the same as in Example 1, except that ceramsite is not used as the raw material. Step 3 of this comparative example involves immersing SAP resin in water for 2 hours to absorb water.

[0133] According to the dry density test conducted in accordance with JG / T 266-2011 "Foamed Concrete", the dry density of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 800 kg / m³. 3 .

[0134] The compressive strength test was conducted according to JG / T 266-2011 "Foamed Concrete". The 7-day compressive strength of the fiber-reinforced crack-resistant foamed concrete board prepared in this embodiment is 4.9 MPa.

[0135] The data from Comparative Examples 8 and 9 above demonstrate that the present invention, by simultaneously adding SAP resin and ceramsite to foamed concrete, achieves a synergistic effect, resulting in stronger water absorption capacity, synergistically improving the strength of foamed concrete, and gradually releasing moisture during the curing process, thereby enhancing the crack resistance of foamed concrete.

[0136] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fiber-reinforced crack-resistant foamed concrete board, characterized in that, It is made of the following components in parts by weight: 500-800 parts cement, 180-300 parts water, 4-8 parts alkali-resistant glass fiber, 3-6 parts ceramic fiber, 3-6 parts basalt fiber, 100-200 parts recycled micro powder, 100-150 parts red brick powder, 100-250 parts diatomaceous earth, 20-40 parts nano foam, 30-80 parts activator, 2-6 parts silane coupling agent, 1-3 parts shrinkage reducer, 2-6 parts expansion agent, 0.1-0.2 parts hydroxypropyl methylcellulose, 20-50 parts SAP resin, and 40-100 parts ceramsite. The nanofoam is formed by physical foaming with a nanofoaming agent; The alkali-resistant glass fiber has a diameter of 10-20 μm and a length of 12-20 mm; the ceramic fiber has a diameter of 150-250 μm and a length of 9-12 mm; the basalt fiber has a diameter of 15-18 μm and a length of 15-20 mm. The recycled micro powder is micro powder produced by crushing waste concrete, and the particle size of the recycled micro powder is 0.075-0.15mm. The particle size of the red brick powder is 0.075-0.15mm, and the SiO2 content of the diatomaceous earth is greater than 95wt%.

2. The fiber-reinforced crack-resistant foamed concrete board according to claim 1, characterized in that, The foamed concrete board is provided with alkali-resistant glass fiber mesh on both sides; the mesh size of the alkali-resistant glass fiber mesh is 10-20mm.

3. The fiber-reinforced crack-resistant foamed concrete board according to claim 1, characterized in that, The cement is one of silicate cement, aluminate cement, or sulfoaluminate cement.

4. The fiber-reinforced crack-resistant foamed concrete board according to claim 1, characterized in that, The activator is one or more of sodium sulfate, sodium carbonate, or sodium silicate.

5. The fiber-reinforced crack-resistant foamed concrete board according to claim 1, characterized in that, The silane coupling agent is a vinyl silane coupling agent; the shrinkage reducing agent is an amino alcohol shrinkage reducing agent; the expanding agent is a calcium carbonate-lime composite expanding agent; the SAP resin is a polyacrylic acid superabsorbent resin with a particle size of 150-200 mesh; and the ceramsite has a particle size of 5-15 mm.

6. The method for preparing the foamed concrete board according to any one of claims 1-5, characterized in that, Includes the following steps: S1. Arrange alkali-resistant glass fiber mesh in the mold for preparing foamed concrete board; S2. Soak SAP resin and ceramsite in water for 2-4 hours to absorb water. S3. After mixing cement, alkali-resistant glass fiber, ceramic fiber and basalt fiber evenly, add silane coupling agent and continue mixing evenly to obtain fiber mixture; S4. Mix the recycled micro powder, red brick powder and diatomaceous earth, stir evenly, then add the activator and continue stirring evenly. S5. Mix the cement, shrinkage reducer, expansion agent, and hydroxypropyl methylcellulose and stir until homogeneous; S6. Add the mixture prepared in steps S2, S3 and S4 to the mixture obtained in step S5, stir evenly, and then add water and stir. S7. Add nano foam to the mixture obtained in step S6, stir, and then quickly transfer it to the mold in step S1, cure, and demold to obtain the final product.

7. The preparation method according to claim 6, characterized in that, In steps S3, S4 and S5, the stirring time is 60-120s; in step S6, the stirring time is 60-120s, and after adding water, the stirring time is 120-180s; in step S7, the stirring time is 90-120s.