Sound absorption main body structure, indoor sludge ceramsite noise reduction brick and preparation method thereof

Abstract

The invention provides a sound absorption main body structure, an indoor sludge ceramsite noise reduction brick and a preparation method of the indoor sludge ceramsite noise reduction brick. The sound absorption main body structure comprises the following components in parts by mass: 30-60 parts of sludge ceramsite, 40-70 parts of a cementing material and 1-5 parts of a water reducing agent. The novel noise-reducing material can be provided by preparing a sound-absorbing main body structure from the sludge ceramsite, the defects that a traditional sound-absorbing material is high in cost and prone to loss due to damp are overcome, resource utilization of municipal sludge can be achieved, and the novel noise-reducing material has wide application prospects.

Description

Technical Field

[0001] The invention relates to the technical field of building materials, and in particular to a sound-absorbing main structure, indoor sludge ceramsite noise reduction bricks and a preparation method thereof. Background Art

[0002] Noise refers to a random or irregular sound that exists in a specific environment. As one of the three major pollutions in the world, it not only damages hearing and destroys mood, but also induces a variety of diseases. The degree of impact on physical and mental health varies in different decibel environments. As my country's urbanization process further accelerates, noise pollution has increasingly become a prominent problem in the urban environment. At present, indoor noise reduction mainly uses porous materials to absorb sound, such as sound-absorbing cotton and sound-absorbing panels. They have the disadvantages of high cost and easy wear and tear due to moisture, making it difficult to adapt to the development of urbanization.

[0003] Therefore, there is an urgent need for a sound-absorbing main structure, indoor sludge ceramsite noise reduction bricks and a preparation method thereof to solve the above-mentioned technical problems. Summary of the invention

[0004] The purpose of the present invention is to provide a sound-absorbing main structure, indoor sludge ceramsite noise reduction bricks and a preparation method thereof, which can overcome the technical problems of high cost and easy loss due to moisture of traditional sound-absorbing materials.

[0005] In order to solve the above technical problems, the present invention first provides a sound-absorbing main structure, comprising the following components in parts by mass: 30 to 60 parts of sludge ceramsite, 40 to 70 parts of gelling material, and 1 to 5 parts of water reducing agent.

[0006] Preferably, the sludge ceramsite comprises 10wt% to 20wt% of the first sludge ceramsite, 30wt% to 50wt% of the second sludge ceramsite and 30wt% to 60wt% of the third sludge ceramsite; The particle size of the first sludge ceramsite is smaller than or equal to the particle size of the second sludge ceramsite, and the particle size of the second sludge ceramsite is smaller than or equal to the particle size of the third sludge ceramsite.

[0007] Preferably, the particle size of the first sludge ceramsite is 1.18 mm to 2.36 mm, the particle size of the second sludge ceramsite is 2.36 mm to 4.75 mm, and the particle size of the third sludge ceramsite is 4.75 mm to 7 mm.

[0008] Preferably, the cementitious material includes at least one of silicate cement, aluminate cement, sulphoaluminate cement, lime, gypsum and water glass.

[0009] Preferably, the water reducing agent includes any one of calcium lignin sulfonate, aminosulfonate compounds and polycarboxylic acid.

[0010] Accordingly, the present invention also provides a sludge ceramsite noise reduction brick for indoor use, comprising a pressure-bearing member and a sound-absorbing main structure as described above; The pressure-bearing member is a hollow structure having an opening on at least one surface, and the sound-absorbing main structure is completely filled in the gap of the pressure-bearing member from the opening.

[0011] Preferably, the pressure-bearing member is formed by solidifying the pressure-bearing slurry, and the pressure-bearing slurry includes the following components in parts by weight: 20 to 40 parts of silicate cement, 30 to 60 parts of standard sand, 3 to 6 parts of fly ash, and 10 to 20 parts of water.

[0012] Accordingly, the present invention further provides a method for preparing the above-mentioned indoor sludge ceramsite noise reduction brick, the method comprising: S10, mixing silicate cement, standard sand, fly ash and water in a uniform proportion, placing the mixture into a first mold for casting, and obtaining a pressure-bearing component after demoulding; S20, mixing the sludge ceramsite, the gelling material, the water reducing agent and the water in proportion and uniformly placing the mixture into a second mold for compression molding, and then demolding the mixture to obtain a sound absorbing main structure; S30, coating the inner wall of the pressure-bearing component with a curing agent, and embedding the sound-absorbing main structure into the interior of the pressure-bearing component through the opening, and obtaining indoor sludge ceramsite noise reduction bricks after the curing agent is cured.

[0013] Preferably, in step S20, the die-casting speed of the die-casting molding process is 80 to 120 N / s, and the holding time is 1 to 2 min.

[0014] Preferably, before performing step S20, the method further includes: subjecting the sludge ceramsite to saturation treatment.

[0015] The beneficial effects of the present invention are as follows: Different from the prior art, the present invention provides a sound-absorbing main structure, indoor sludge ceramsite noise reduction bricks and a preparation method thereof, wherein the sound-absorbing main structure comprises the following components by mass: 30 to 60 parts of sludge ceramsite, 40 to 70 parts of cementitious material, and 1 to 5 parts of water reducer. The present invention can provide a new noise reduction material by using sludge ceramsite to prepare the sound-absorbing main structure, overcome the shortcomings of traditional sound-absorbing materials such as high cost and easy loss due to moisture, and realize the resource utilization of urban sludge, which has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A sound absorption principle diagram of the sludge ceramsite provided by the present invention; Figure 2 A flow chart of a method for preparing indoor sludge ceramsite noise reduction bricks provided by an embodiment of the present invention; Figure 3 A physical photo of the indoor sludge ceramsite noise reduction brick provided in Example 1 of the present invention; Figure 4 A physical photo of the sound-absorbing main structure of the indoor sludge ceramsite noise reduction brick provided in Example 3 of the present invention; Figure 5 This is a curve diagram of the sound absorption coefficient of the sound-absorbing main structure of the indoor sludge ceramsite noise reduction brick provided in Example 3 of the present invention. DETAILED DESCRIPTION

[0017] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] In view of the technical problems that traditional sound-absorbing materials are high in cost and easy to be damaged by moisture, the present invention can provide a new noise reduction material by using sludge ceramsite to prepare the sound-absorbing main structure, thereby overcoming the shortcomings of traditional sound-absorbing materials such as high cost and easy to be damaged by moisture, and realizing the resource utilization of urban sludge, which has broad application prospects.

[0019] To achieve the above object, the present invention provides the following technical solutions: In a first aspect, the present invention first provides a sound-absorbing main structure, comprising the following components in parts by weight: 30 to 60 parts of sludge ceramsite, 40 to 70 parts of gelling material, and 1 to 5 parts of water reducing agent.

[0020] In the embodiment of the present invention, the sludge ceramsite is an important component of the sound-absorbing main structure. The sludge ceramsite has a porous structure and can effectively absorb sound energy. The pores inside it can cause sound waves to be repeatedly reflected, refracted and absorbed therein, thereby reducing the propagation intensity of the sound.

[0021] See also Figure 1 , Figure 1 The sound absorption principle diagram of the sludge ceramsite provided by the present invention; wherein, E is the total incident energy, Er To reflect part of the energy, Ea is the energy of the interaction within the material. E To project energy, the principle can be summarized as follows: sludge ceramsite is a porous material, and the pores inside it can be regarded as composed of narrow pipes; when sound waves enter the porous material, part of it is reflected, and the other part enters the material and propagates, where it is reflected and scattered many times. In the process of absorbing sound wave energy, various interactions of energy exchange occur in the porous material, and the sound waves collide and rub in the pores, converting the sound wave energy into heat energy, thereby weakening the sound wave energy entering the material.

[0022] Specifically, urban sludge refers to the solid waste generated during the treatment of urban domestic sewage, which is mainly processed by water treatment plants through sludge treatment facilities. These sludges usually contain a large amount of organic matter, microorganisms, wastewater treatment agents, sediments and various pollutants from urban life. At present, the main domestic sludge treatment methods include sludge landfill, sludge incineration, sludge composting, sludge drying and other means, which not only occupy land resources but also easily cause secondary pollution. The use of sludge ceramsite also realizes the resource utilization of sludge and reduces pollution to the environment. It has the characteristics of light weight, reduces the overall weight of the sound-absorbing main structure, and is easy to install and transport.

[0023] Specifically, when the mass fraction of sludge ceramsite is 30 to 60 parts, the content of sludge ceramsite is moderate, which can ensure that the sound-absorbing main structure has a good sound absorption effect. If the mass content of sludge ceramsite is less than 30 parts, the porosity is insufficient and the sound absorption performance will be greatly reduced; if the mass content of sludge ceramsite is greater than 60 parts, it will affect the integrity and stability of the sound-absorbing main structure; the use of sludge ceramsite realizes the resource utilization of sludge and reduces pollution to the environment. At the same time, compared with other traditional sound-absorbing materials, the cost of sludge ceramsite is relatively low. Within this ratio range, both sludge resources can be fully utilized and costs can be controlled.

[0024] In the embodiment of the present invention, 10wt% to 20wt% of the first sludge ceramsite, 30wt% to 50wt% of the second sludge ceramsite and 30wt% to 60wt% of the third sludge ceramsite; The particle size of the first sludge ceramsite is smaller than or equal to the particle size of the second sludge ceramsite, and the particle size of the second sludge ceramsite is smaller than or equal to the particle size of the third sludge ceramsite.

[0025] Specifically, the first sludge ceramsite usually has a smaller particle size and accounts for a smaller proportion in the sludge ceramsite. Its role may be to fill the gaps between the larger particle size sludge ceramsite to increase the density of the overall structure. Due to the small particle size and relatively large specific surface area, it can be better combined with the cementitious material to improve the bonding strength. At the same time, the first sludge ceramsite with a small particle size may play a unique role in sound absorption performance and can absorb higher frequency sounds.

[0026] Specifically, the proportion of the second sludge ceramsite is relatively high, and its particle size is larger than that of the first sludge ceramsite. In the sludge ceramsite, the second sludge ceramsite plays the role of skeleton support. The larger particle size gives it a certain strength and stability, and it can withstand a certain pressure. At the same time, the gaps formed between the second sludge ceramsite can provide a channel for the propagation and absorption of sound, and work synergistically with the first sludge ceramsite and the third sludge ceramsite to improve the sound absorption effect.

[0027] Specifically, the third sludge ceramsite is the part with the largest particle size in the sludge ceramsite, and its proportion is relatively high. Its main function is to provide a larger pore space, which is conducive to the reflection, refraction and absorption of sound in it. The third sludge ceramsite with large particle size can reduce the packing density of the sludge ceramsite, making the sound-absorbing main structure lighter. In addition, the third sludge ceramsite can also affect the air permeability and drainage performance of the sound-absorbing main structure, avoiding the influence of water accumulation on the sound absorption effect.

[0028] In one embodiment, the particle size of the first sludge ceramsite is 1.18 mm to 2.36 mm, the particle size of the second sludge ceramsite is 2.36 mm to 4.75 mm, and the particle size of the third sludge ceramsite is 4.75 mm to 7 mm.

[0029] In the embodiment of the present invention, the cementitious material mainly plays the role of bonding and solidification, bonding the granular materials such as sludge ceramsite together to form a solid whole. Within this ratio range, the content of the cementitious material can ensure that the sludge ceramsite is fully bonded, so that the sound absorption main structure has sufficient strength and stability. If the content is too low, the bonding force is insufficient and the structure is easy to loosen; if the content is too high, the structure may be too hard, affecting the sound absorption performance.

[0030] In one embodiment, the cementitious material includes at least one of silicate cement, aluminate cement, sulphoaluminate cement, lime, gypsum and water glass.

[0031] In the embodiment of the present invention, the main function of the water reducer is to reduce the amount of water used for mixing while ensuring the workability of the sound absorbing main structure. Within this ratio range, the water reducer can effectively reduce the water demand of the cementitious material and improve its fluidity and density. This helps to improve the construction performance of the sound absorbing main structure, making it easier to cast and shape. At the same time, an appropriate amount of water reducer can reduce the generation of pores and cracks, and improve the strength and durability of the sound absorbing main structure. At the same time, the water reducer can also improve the interfacial bonding performance between the cementitious material and the sludge ceramsite, further enhancing the integrity of the structure.

[0032] In one embodiment, the water reducing agent includes any one of calcium lignin sulfonate, aminosulfonate compounds and polycarboxylic acid.

[0033] Accordingly, the present invention also provides an indoor sludge ceramsite noise reduction brick, the indoor sludge ceramsite noise reduction brick comprising a pressure-bearing member and any one of the above sound-absorbing main structures; The pressure-bearing member is a hollow structure having an opening on at least one surface, and the sound-absorbing main structure is completely filled in the gap of the pressure-bearing member from the opening.

[0034] Specifically, the rich porous structure of sludge ceramsite itself leads to low compressive strength, and the compressive strength alone is far from meeting the use requirements. Therefore, the present invention separately prepares the pressure-bearing component, and the pressure-bearing component mainly bears the load during use.

[0035] Specifically, the pressure-bearing member is a hollow structure with an opening on at least one side, which provides a basic structural framework and strength support for the entire indoor sludge ceramsite noise reduction brick. It can withstand a certain pressure and load to ensure that the indoor sludge ceramsite noise reduction brick will not be easily damaged or deformed during use. For example, when laying the indoor floor, the pressure-bearing member can withstand the pressure of people walking and the placement of furniture.

[0036] At the same time, the hollow pressure-bearing member allows the sound-absorbing main structure to be filled in through the opening, which plays a role in limiting and fixing the sound-absorbing main structure. This can prevent the sound-absorbing main structure from scattering or shifting during use, ensuring the overall performance of the noise reduction brick is stable. Especially in some environments that may be subject to vibration or external force impact, the pressure-bearing member can effectively protect the sound-absorbing main structure and extend the service life of the noise reduction brick.

[0037] In the embodiment of the present invention, the pressure-bearing member is formed by solidifying the pressure-bearing slurry, and the pressure-bearing slurry includes the following components in parts by weight: 20 to 40 parts of silicate cement, 30 to 60 parts of standard sand, 3 to 6 parts of fly ash, and 10 to 20 parts of water.

[0038] Specifically, silicate cement is the main cementitious material of the pressure-bearing slurry. After mixing with water, it undergoes hydration reaction to form a hardened body with strength; standard sand plays the role of filling the skeleton in the pressure-bearing slurry. After mixing with materials such as cement and fly ash, it forms a dense structure, which improves the strength and stability of the pressure-bearing components; fly ash is an industrial waste residue with volcanic ash activity. Adding an appropriate amount of fly ash to the pressure-bearing slurry can improve the slurry's workability, fluidity, durability and other properties.

[0039] See also Figure 2 , Figure 2 A flow chart of a method for preparing indoor sludge ceramsite noise reduction bricks provided by an embodiment of the present invention; wherein the method for preparing the indoor sludge ceramsite noise reduction bricks comprises: S10, after uniformly mixing silicate cement, standard sand, fly ash and water in proportion, putting the mixture into a first mold for casting and molding, and obtaining a pressure-bearing component after demoulding.

[0040] S20, after the sludge ceramsite, the cementitious material, the water reducing agent and the water are uniformly mixed in proportion, the mixture is put into a second mold for compression molding, and the sound absorbing main structure is obtained after demolding.

[0041] Specifically, before performing step S20, the process also includes: saturating the sludge ceramsite with water; wherein, the sludge ceramsite has a high water absorption rate because of its rich pore structure inside and its raw material sludge itself has strong water absorption. In order to ensure that the cementitious material in the sound-absorbing main material provided by the present invention can be hydrated according to the prescribed water-cement ratio, the sludge ceramsite needs to be saturated with water in advance.

[0042] In one embodiment, in step S20, the die-casting speed of the die-casting molding process is 80-120 N / s, and the holding time is 1-2 min.

[0043] Specifically, a moderate die-casting speed can ensure that the material is evenly stressed during the pressing process. If the rolling speed is too fast, it may cause uneven stress distribution inside the material, resulting in defects such as cracks and delamination in the pressure-bearing components. For example, when the die-casting speed exceeds 120N / s, the material may not have time to adapt to the instantaneous pressure changes, and local areas may be over-stressed and destroy the integrity of the structure. On the other hand, if the rolling speed is too slow, below 80N / s, although the material is relatively evenly stressed, it will extend the production cycle and reduce production efficiency. Moreover, during the slower pressing process, the material may have more time to undergo creep and other phenomena, affecting the final dimensional accuracy and strength properties.

[0044] Specifically, sufficient holding time can fully compact the material under pressure, expel the internal air and excess moisture, and improve the density and strength of the pressure-bearing components. If the holding time is too short, less than 1 minute, the material may not be fully compacted, and there will be gaps and loose areas inside, which will significantly reduce the bearing capacity and durability of the component. For example, in actual use, an insufficiently compacted pressure-bearing component may be deformed or damaged under a small load. However, if the holding time is too long, more than 2 minutes, although the density can be further improved, it will increase production costs and production cycles, and may also have an adverse effect on the performance of the material. For example, too long a period of pressure may cause excessive hydration of cement, making the component too hard and lacking toughness.

[0045] S30, coating the inner wall of the pressure-bearing component with a curing agent, and embedding the sound-absorbing main structure into the interior of the pressure-bearing component through the opening, and obtaining indoor sludge ceramsite noise reduction bricks after the curing agent is cured.

[0046] The above-mentioned sound-absorbing main structure, indoor sludge ceramsite noise reduction brick and its preparation method are described in detail below through specific embodiments.

[0047] Embodiment 1: Example 1 of the present invention uses sludge ceramsite produced by Wuhan Juhai Environmental Technology Co., Ltd. in Hubei Province, which is made of urban sludge as raw material, mixed with auxiliary raw materials and flux and roasted through a certain process flow. It has the characteristics of light weight, low density, and rich internal pores. Its specific components are shown in Table 1: Table 1 Chemical composition of sludge ceramsite

[0048] Among them, the gaseous carbon dioxide can be inferred from the high-temperature decomposition reaction equation that it is generated by the high-temperature decomposition of calcium carbonate, magnesium carbonate and potassium carbonate.

[0049] In Example 1 of the present invention, the sludge ceramsite includes 15wt% of the first sludge ceramsite, 45wt% of the second sludge ceramsite and 40wt% of the third sludge ceramsite; the particle size of the first sludge ceramsite is 1.18mm~2.36mm, the particle size of the second sludge ceramsite is 2.36mm~4.75mm, and the particle size of the third sludge ceramsite is 4.75mm~7mm.

[0050] Specifically, the aggregate density of the above-mentioned sludge ceramsite is determined according to the test specification GB / T 14684-2022, and the test results are shown in Table 2 below: Table 2 Aggregate density of sludge ceramsite

[0051] In Example 1 of the present invention, the cementitious material is PO42.5 ordinary Portland cement produced by Zhucheng Yangchun Cement Company, and its main properties are shown in Table 3: Table 3 Main properties of PO42.5 ordinary Portland cement

[0052] Among them, the main properties of the above-mentioned PO42.5 ordinary Portland cement all meet the requirements of the specifications.

[0053] In Example 1 of the present invention, the water reducing agent is polycarboxylic acid. If the water-cement ratio is high and the cement paste is thin, the cement paste will flow downward under the action of gravity after the material is made to block the pores at the bottom, thereby reducing the overall sound absorption performance of the material. Therefore, adding a water reducing agent allows less water to react with the cement at the same amount of cement, thereby improving its sound absorption performance.

[0054] Specifically, the physical performance indicators of the water reducing agent are shown in Table 4: Table 4 Physical performance indexes of polycarboxylate water reducer

[0055] Specifically, the sound absorbing main structure provided by Example 1 of the present invention includes the following components in parts by mass: 50 parts of sludge ceramsite, 50 parts of gelling material, and 1 part of water reducing agent.

[0056] Specifically, Accordingly, embodiment 1 of the present invention further provides a sludge ceramsite noise reduction brick for indoor use, comprising a pressure-bearing member and a sound-absorbing main structure as described above; The pressure-bearing member is a hollow structure having an opening on at least one surface, and the sound-absorbing main structure is completely filled in the gap of the pressure-bearing member from the opening.

[0057] In Example 1 of the present invention, the pressure-bearing member is formed by solidifying the pressure-bearing slurry, and the pressure-bearing slurry includes the following components in parts by weight: 20 parts of PO42.5 ordinary Portland cement, 30 parts of standard sand, 3 parts of fly ash, and 10 parts of water, and its water-cement ratio is 0.5.

[0058] Specifically, the fly ash provided in Example 1 of the present invention adopts ultrafine fly ash, and its main chemical components are shown in Table 5: Table 5 Main chemical components of fly ash

[0059] Accordingly, Example 1 of the present invention further provides a method for preparing the above-mentioned indoor sludge ceramsite noise reduction brick, and the method specifically comprises: Step (1): PO42.5 ordinary Portland cement, standard sand, and fly ash are mixed in a water-cement ratio of 0.5, cement: standard sand: mixing water = 2:3:1, and fly ash is used to replace cement at a mass ratio of 15%. After pouring in a special first mold (a rectangular hollow specimen with a wall thickness of 1 cm), it is cured for 14 days under a standard curing environment of 20±2°C and a humidity of more than 95% to form a pressure-bearing component.

[0060] Step (2): Saturate the sludge ceramsite with water in advance, add ordinary tap water to the sludge ceramsite until the surface of the sludge ceramsite is completely covered by 1 to 2 cm, and allow the sludge ceramsite to fully absorb water. After 24 hours, drain the remaining water and place the sludge ceramsite in an oven to dry until there is no moisture on the surface.

[0061] Step (3): Add all 50 parts of the pre-treated sludge ceramsite (including 15wt% of the first sludge ceramsite, 45wt% of the second sludge ceramsite and 40wt% of the third sludge ceramsite) and 50 parts of PO42.5 ordinary Portland cement into a cement mortar mixer and dry mix for 30 seconds to allow the PO42.5 ordinary Portland cement to fully coat the surface of the sludge ceramsite. Subsequently, add 1 part of polycarboxylate water reducer and add mixing water in two portions, and stir thoroughly for 1 minute until the surface of the sludge ceramsite is loose and moist.

[0062] Step (4): Remove the mixing pot, scrape the mixture on the sides of the mixing pot and the blades into the middle of the pot, wipe the second mold clean, apply butter on the sides to facilitate subsequent demoulding, and assemble tightly to prevent leakage.

[0063] Step (5): Place the filled second mold under the press, control the loading speed to 100 N / s and press to the standard size, maintain the pressure for 1 minute, and remove the mold after molding. The size is 220 mm × 115 mm × 53 mm. Cured under standard curing conditions for 14 days, and dried after the curing time is full to prevent residual moisture in the pores from affecting the determination of the sound absorption coefficient.

[0064] Step (6): Evenly coat the inner wall of the pressure-bearing component with epoxy resin, and directly embed the cured sound-absorbing main body into the pressure-bearing component. Gel it at room temperature for 2-3 hours, and completely cure it for 24 hours to form a complete indoor sludge ceramsite noise reduction brick. The size is the same as the standard brick size: 240mm long, 115mm wide, and 53mm high. Figure 3 shown.

[0065] Embodiment 2: Example 2 of the present invention provides an indoor sludge expanded clay noise reduction brick, and its structure is roughly the same as that of Example 1, except that the indoor sludge expanded clay noise reduction brick provided in Example 2 of the present invention is a cylindrical specimen with a diameter of 100 mm and a height of 100 mm.

[0066] Specifically, the compressive strength test of the indoor sludge ceramsite noise reduction brick provided in Example 2 of the present invention is carried out, and the specific process is as follows: The compressive strength test was carried out according to the test method specified in GB / T 50081-2019 "Standard for Test Methods for Mechanical Properties of Ordinary Concrete". The universal testing machine was used for loading, and 3 groups of parallel specimens were set up. The loading rate was 0.5 MPa / s as specified in the specification, and the specimen size was planned to be a cylindrical specimen with a diameter of 100 mm and a height of 100 mm. Since the testing machine is set to load Newtons per second, 0.5MPa / s is converted to 3.9×10 3 N / s, the arithmetic mean of three groups of parallel specimens is taken as the final compressive strength of the indoor sludge ceramsite noise reduction brick. The test results are shown in Table 6: Table 6 Compressive strength test of Example 2 of the present invention

[0067] Specifically, it can be seen from Table 6 that the measured compressive strength of the indoor sludge expanded clay noise reduction brick provided in Example 2 of the present invention is 20.51 MPa. Referring to the classification of the environmental categories of masonry structures in the standard GB 55007-2021 "General Specification for Masonry Structures", the environment in which the indoor sludge expanded clay noise reduction brick provided in Example 2 of the present invention is used can be divided into Class 1, and the standard stipulates that the minimum strength grade of block materials in Class 1 environment stipulates that the minimum strength of concrete bricks is MU15, that is, the average compressive strength is not less than 15 MPa. Therefore, the indoor sludge expanded clay noise reduction brick provided in Example 2 of the present invention meets the above strength requirements.

[0068] Embodiment 3: Embodiment 3 of the present invention provides a sound-absorbing main structure, indoor sludge ceramsite noise reduction bricks and a preparation method thereof, which are substantially the same as Embodiment 1, except that: The sound absorbing main structure provided in Example 3 of the present invention is a cylindrical specimen with a diameter of 100 mm and a thickness of 30 mm. Figure 4 shown.

[0069] Specifically, the sound absorption coefficient of the sound absorbing main structure in the indoor sludge ceramsite noise reduction brick provided in Example 3 of the present invention is tested, and the specific process is as follows: The determination of sound absorption coefficient refers to the current standard GB / T 18696.1-2004 "Measurement of sound absorption coefficient and acoustic impedance in acoustic impedance tubes Part 1: Standing wave ratio method", which mainly tests the sound absorption coefficient of the sound absorption main body. While keeping the same ratio unchanged, the test piece is made into a cylinder with a thickness of 30mm and a diameter of 100mm. Figure 4 As shown in the figure, the sound absorption coefficient at 0~1600Hz is tested by using a standing wave tube, and the following is plotted: Figure 5 The sound absorption coefficient graph is shown.

[0070] Specifically, by Figure 5 It can be seen that according to the method specified in Section 4.1 of the practical sound absorption coefficient in the standard GB / T 16731-2023 "Sound absorption performance classification of building sound absorption products" and the method of grading the sound absorption performance of building sound absorption products according to the noise reduction coefficient (NRC) in Appendix D, the practical sound absorption coefficient of each octave band and the product noise reduction coefficient are calculated as shown in Table 7, and the sound absorption performance classification of the sound-absorbing main structure of the indoor sludge ceramsite noise reduction brick provided in Example 3 of the present invention belongs to Grade IV.

[0071] Table 7 Practical sound absorption coefficient and noise reduction coefficient

[0072] Therefore, based on the above compression test and sound absorption coefficient test data, it can be concluded that the indoor sludge expanded clay noise reduction bricks produced by the present invention meet the strength requirements for concrete bricks in the "General Specifications for Masonry Structures", and the sound absorption performance classification belongs to Level IV, which meets the indoor noise reduction needs and can be used for indoor noise reduction building materials, such as background walls, etc.

[0073] In summary, different from the prior art, the present invention provides a sound-absorbing main structure, indoor sludge ceramsite noise reduction bricks and a preparation method thereof, wherein the sound-absorbing main structure comprises the following components by mass: 30 to 60 parts of sludge ceramsite, 40 to 70 parts of cementitious material, and 1 to 5 parts of water reducer. The present invention can provide a new noise reduction material by using sludge ceramsite to prepare the sound-absorbing main structure, overcome the shortcomings of traditional sound-absorbing materials such as high cost and easy loss due to moisture, and realize the resource utilization of urban sludge, which has broad application prospects.

[0074] It should be noted that the above embodiments all belong to the same inventive concept, and the descriptions of the embodiments have different focuses. For the parts not described in detail in the individual embodiments, reference can be made to the descriptions in other embodiments. The above embodiments only express the implementation methods of the present invention, and the descriptions are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims

1. A sound absorbing main structure, characterized in that: The invention comprises the following components in parts by weight: 30 to 60 parts of sludge ceramsite, 40 to 70 parts of cementitious material and 1 to 5 parts of water reducing agent.

2. The sound absorbing main structure according to claim 1, characterized in that: The sludge ceramsite comprises 10wt% to 20wt% of the first sludge ceramsite, 30wt% to 50wt% of the second sludge ceramsite and 30wt% to 60wt% of the third sludge ceramsite; The particle size of the first sludge ceramsite is smaller than or equal to the particle size of the second sludge ceramsite, and the particle size of the second sludge ceramsite is smaller than or equal to the particle size of the third sludge ceramsite.

3. The sound absorbing main structure according to claim 2, characterized in that: The particle size of the first sludge ceramsite is 1.18 mm to 2.36 mm, the particle size of the second sludge ceramsite is 2.36 mm to 4.75 mm, and the particle size of the third sludge ceramsite is 4.75 mm to 7 mm.

4. The sound absorbing main structure according to claim 1, characterized in that: The cementitious material includes at least one of silicate cement, aluminate cement, sulphoaluminate cement, lime, gypsum and water glass.

5. The sound absorbing main structure according to claim 1, characterized in that: The water reducing agent includes any one of calcium lignin sulfonate, aminosulfonate compounds and polycarboxylic acid.

6. A kind of indoor sludge ceramsite noise reduction brick, characterized in that: It comprises a pressure-bearing member and a sound-absorbing main structure as claimed in any one of claims 1 to 5; Wherein, the pressure-bearing member is a hollow structure having an opening on at least one surface, and the sound-absorbing main structure is completely filled in the gap of the pressure-bearing member from the opening.

7. The indoor sludge ceramsite noise reduction brick according to claim 6, characterized in that: The pressure-bearing component is formed by solidifying the pressure-bearing slurry, and the pressure-bearing slurry includes the following components in parts by mass: 20 to 40 parts of silicate cement, 30 to 60 parts of standard sand, 3 to 6 parts of fly ash, and 10 to 20 parts of water.

8. A method for preparing indoor sludge ceramsite noise reduction bricks according to any one of claims 6 to 7, characterized in that: The method comprises: S10, mixing silicate cement, standard sand, fly ash and water in proportion and uniformly mixing the mixture, placing the mixture into a first mold for casting and molding, and obtaining the pressure-bearing member after demoulding; S20, mixing the sludge ceramsite, the gelling material, the water reducing agent and the water in a uniform proportion, placing the mixture into a second mold for die-casting, and demolding to obtain the sound absorbing main structure; S30, coating the inner wall of the pressure-bearing component with a curing agent, and embedding the sound-absorbing main structure into the interior of the pressure-bearing component through the opening, and obtaining the indoor sludge ceramsite noise reduction brick after the curing agent is cured.

9. The method for preparing indoor sludge ceramsite noise reduction bricks according to claim 8, characterized in that: In the step S20, the die-casting speed of the compression molding process is 80 to 120 N / s, and the holding time is 1 to 2 min.

10. The method for preparing indoor sludge ceramsite noise reduction bricks according to claim 8, characterized in that: Before performing the step S20, the method further includes: subjecting the sludge ceramsite to a saturated water treatment.

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