3D printing material based on decoration waste reclaimed material, preparation method of 3D printing material and application of 3D printing material in 3D printing sound barrier

Abstract

The invention relates to a 3D printing material based on a decoration waste recycled material, a preparation method of the 3D printing material and application of the 3D printing material to a 3D printing sound barrier. The 3D printing material comprises the following components in parts by weight: 50 parts of decoration waste lightweight aggregate; 90 to 120 parts of cement; 30 to 45 parts of water; 1-2 parts of a thickening agent; 5 to 7 parts of nano clay; 0.5 to 1.0 part of a retarder; 0.5 to 1.0 part of a water reducing agent; the decoration garbage lightweight aggregate is selected from at least one of waste aerated blocks, waste wood, waste rubber or waste plastic. The 3D printing material is used for constructing a sound barrier with more excellent sound absorption and insulation functions through a 3D printing technology. Compared with the prior art, high-quality utilization of the construction waste is achieved, meanwhile, the technical advantages of 3D printing are fully utilized, and the sound barrier which is provided with sound absorption cavities and stripe structures and can be continuously printed on site or prefabricated in batches in a factory is designed and built.

Description

Technical Field

[0001] The present invention belongs to the field of building materials and construction technology, and relates to a 3D printing material based on recycled decoration waste, a preparation method thereof, and an application thereof in 3D printing sound barriers. Background Art

[0002] As the living standards of urban residents in my country improve, the number of old house renovation and expansion projects increases. In recent years, the amount of renovation waste has increased dramatically, and the annual amount has exceeded 300 million tons. Renovation waste is highly mixed and difficult to handle. Recycled aggregates can be obtained through crushing, sorting and screening. Among them, heavy aggregates (such as waste concrete, waste bricks and other materials) obtained by density sorting can still be used to prepare recycled aggregate concrete. A large number of studies have proved the feasibility of this utilization approach. However, the remaining lightweight aggregates (such as waste aerated blocks, waste wood, waste rubber) have low density, high impurity content, many pores, high water absorption, low strength and other factors. The prepared recycled products have poor performance and are not suitable for preparing structural load-bearing components. It is difficult to use them through conventional means (i.e., preparing load-bearing components such as recycled concrete). Most of them are limited to low-quality applications such as brick making or landfill (such as patent CN115448655A and patent CN117049836A). In addition, the disposal path of lightweight aggregates is single, and the technology for high-quality utilization is even more lacking.

[0003] Noise pollution is very common in people's daily work and life. For example, noise pollution is particularly prominent in scenes where noise is continuously generated, such as highways, construction sites, and KTVs. Noise can seriously affect people's normal life and work, and cause harm to people's physical and mental health. Traditional metal sound barriers have a relatively simple structure, high cost, easy to corrode, and short service life. Traditional cement sound barriers are generally cement veneers, usually with a flat structure, which are not ideal for noise reduction and dispersion, and have poor noise reduction effects. Summary of the invention

[0004] The purpose of the present invention is to provide a 3D printing material based on recycled materials from renovation waste, a preparation method thereof, and its application in 3D printing sound barriers. Specifically, recycled materials are prepared from construction and renovation waste, and 3D printing materials are prepared using this as raw material, and a sound barrier with better sound absorption and sound insulation functions is constructed through 3D printing technology. On the one hand, the present invention can avoid the disadvantages of lightweight aggregates from renovation waste, because the sound barrier does not need to be subjected to force, and on the other hand, it can give full play to the advantages of lightweight aggregates from renovation waste. Lightweight and high-porosity renovation waste is used as raw material, which reduces the density of 3D printed strips and is conducive to improving the constructability of 3D printing, while the porosity is conducive to increasing the porosity of the sound barrier and enhancing the sound absorption effect of the sound barrier. Therefore, through the 3D printing material and preparation method provided by the present invention, high-quality utilization of lightweight aggregates from renovation waste can be achieved, and high-value-added sound barrier products can be prepared.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] The first aspect of the present invention provides a 3D printing material based on recycled decoration waste, comprising the following components in parts by weight:

[0007]

[0008] The decoration waste lightweight aggregate is selected from at least one of waste aerated blocks, waste wood, waste rubber or waste plastic.

[0009] Furthermore, the cement is ordinary Portland cement; the thickener is hydroxypropyl methylcellulose ether; the retarder is sodium gluconate; and the water reducer is a polycarboxylic acid-based water reducer.

[0010] Furthermore, the strength grade of the ordinary Portland cement is PO42.5 or above, and the density is 3100kg / m 3 .

[0011] Furthermore, the viscosity of the hydroxypropyl methylcellulose ether is 200000 mPa·s.

[0012] Furthermore, the water reduction rate of the polycarboxylic acid high-efficiency water reducer is ≥25%.

[0013] Furthermore, the decoration waste lightweight aggregate is derived from the lightweight aggregate obtained in the light-heavy separation process. The decoration waste lightweight aggregate has the characteristics of light weight and high porosity, making the surface of the sound barrier rough and porous, which is conducive to absorbing sound waves.

[0014] Furthermore, the density of the decoration waste lightweight aggregate is less than 1000kg / m 3 The average particle size is less than 2.36mm and the fineness modulus is 2.2-2.8.

[0015] Furthermore, in the lightweight aggregate of renovation waste, the volume proportion of the waste aerated blocks, waste wood or waste rubber is greater than 95%.

[0016] Furthermore, among the decoration waste lightweight aggregate, the decoration waste lightweight aggregate is mainly waste aerated blocks (accounting for 70-80% by volume), waste wood accounts for 10%-15% by volume, the waste rubber accounts for 5%-10% by volume, and the remaining substances account for ≤5% by volume.

[0017] A second aspect of the present invention provides a method for preparing a 3D printing material, comprising the following steps:

[0018] 1) Add water to the decoration waste lightweight aggregate and stir it to make the decoration waste lightweight aggregate fully absorb water and reach a saturated state;

[0019] 2) The fully water-absorbed lightweight aggregate of renovation waste is stirred and mixed with cement and water, and then a thickener, nanoclay, a retarder and a water reducing agent are added, and the stirring and mixing are continued to obtain the 3D printing material.

[0020] Furthermore, in step 2), when the lightweight aggregate of renovation waste is mixed with cement and water, a forced mixer is used to stir for more than 90 seconds to ensure uniform mixing.

[0021] Furthermore, in step 2), the amount of the water reducer is determined according to the flow state of the mixture during stirring. In this process, the water reducer needs to be added in multiple times to obtain the 3D printing material. When the mixture is thick, that is, the fluidity is less than 160 mm, the water reducer needs to be added to continue stirring, and the flow state is tested again, and so on, until the fluidity of the mixture reaches between 160 and 200 mm. If the mixture is found to be too thin in the first test, that is, the fluidity is significantly greater than 200 mm, the formula is modified (the amount of water added is reduced) and re-prepared.

[0022] A third aspect of the present invention provides an application of a 3D printing material in a 3D printing sound barrier, wherein the 3D printing material is used to prepare the sound barrier.

[0023] Furthermore, the 3D printed material is used to prepare a sound barrier through 3D printing technology, and the sound barrier is constructed by a 3D printer through layer-by-layer stacking, specifically using a 3D printer for on-site in-situ construction or engineering batch printing and construction, followed by on-site in-situ maintenance or on-site assembly of prefabricated parts.

[0024] Furthermore, 3D printing technology has the characteristics of layer-by-layer construction, no template support, and personalized customization, which can more conveniently realize the manufacture of sound barriers with personalized appearance design. The purpose of using 3D printing technology to build sound barriers is to give full play to the advantages of 3D printing technology in high design freedom, low labor density, saving materials and time, and low carbon emissions. Taking the sound barriers on both sides of the road as an example, the general sound barriers are built with flat barrier panels, which are difficult to fit when encountering curved roads. However, 3D printing technology can be used to build along the curve of the road. When encountering more complex working conditions, 3D printing technology can also adapt and carry out targeted design.

[0025] Furthermore, the shape of the sound barrier is a wall with a cavity. Due to the use of 3D printing technology, the wall can be built along a curve or a straight line to form a curved wall or a straight wall to meet the actual needs of the road edge or the building edge.

[0026] Furthermore, the sound barrier includes a sound barrier body, a plurality of unit cavities arranged in parallel in the sound barrier body, and a plurality of sound absorption channels opened on one side of the sound barrier body and connected to the corresponding unit cavities, and the unit cavities and the sound absorption channels are respectively arranged to penetrate in the height direction; the sound barrier also includes a base arranged at the bottom of the sound barrier body, and a top plate arranged at the top of the sound barrier body, and the base and the top plate are both provided with a plurality of through holes connected to the corresponding unit cavities. The sound barrier body has a sound wave blocking effect. In order to give full play to the sound absorption function of the sound barrier cavity, all unit cavities are reserved with a sound absorption channel for allowing external noise to enter the plurality of unit cavities, and the noise is reduced through the absorption and reflection of the inner wall of the cavity and the principle of sound wave interference inside the cavity. In addition to the sound barrier body with the sound absorption channel, the sound barrier also has a base and a top plate of a certain height. The base and the top plate have no sound absorption channels, but only cavities, that is, a plurality of through holes connected to the corresponding unit cavities.

[0027] Furthermore, the cross-section of the unit cavity is square, fan-shaped, or trapezoidal; when the sound barrier is constructed along a straight line, the unit cavity can be square, and when the sound barrier is constructed along a curve, the unit cavity can be transformed into special shapes such as trapezoidal or fan-shaped according to actual conditions.

[0028] Further, the sound absorption hole is arranged in the center relative to the unit cavity along the width direction; or, a side edge of the sound absorption hole is flush with the side wall of the unit cavity.

[0029] Furthermore, when the cross section of the unit cavity is square, the width a of the unit cavity and the width d of the sound absorption channel satisfy: d / a<0.5; the height of the sound barrier is 1 to 5 m; the height of the base and the top plate is 0.1 to 0.5 m; the thickness of the sound barrier body is 40 to 80 mm. The higher the height of the sound barrier, the better the sound insulation effect.

[0030] Furthermore, the sound barrier body is composed of at least two parallel 3D printed strips, and the sound barrier body constructs multiple internal cavities and an overall external structure of the sound barrier through a certain path, and the sound barrier body is the only physical structure of the sound barrier.

[0031] Furthermore, when the sound absorption hole is centered relative to the unit cavity along the width direction, a hole-centered unit cavity is formed, and the hole-centered unit cavity satisfies x=(ad) / 2, d / a<0.5, 0≤x≤ad; when one side edge of the sound absorption hole is flush with the side wall of the unit cavity, a hole-side unit cavity is formed, and the hole-side unit cavity satisfies x=ad, d / a<0.5, 0≤x≤ad, wherein a is the width of the unit cavity, b is the length of the unit cavity, d is the width of the sound absorption hole, and x is the position parameter of the sound absorption hole.

[0032] Furthermore, preparing the sound barrier comprises the following steps:

[0033] S1: Load the 3D printing material into the silo of the 3D printer and start the stirring screw of the 3D printer;

[0034] S2: Input a printing path into the 3D printer, move the print head of the 3D printer to the origin, start printing, and obtain the sound barrier.

[0035] Furthermore, in step S1, after the stirring screw of the 3D printer is turned on, the printing status of the 3D printing material is tested. When the 3D printing material can be printed continuously without interruption and can be stably stacked without collapse or large deformation, it indicates that the 3D printing material can start printing.

[0036] Furthermore, the 3D printer is a mortar / concrete 3D printer; the strip width of the printing of the 3D printer is 20 to 40 mm, the strip height is 10 to 20 mm, and the horizontal printing speed is 10 to 50 mm / s.

[0037] Furthermore, the caliber of the extruder head of the 3D printer is 20 to 40 mm.

[0038] Furthermore, the sound barrier is suitable for noise reduction on both sides of highways, noise insulation and noise reduction around construction sites, noise absorption in buildings, etc.

[0039] The present invention covers the formula design of decoration waste recycled materials (3D printing materials) for 3D printing and the structural design and construction method of 3D printing sound barriers. The 3D printing sound barriers use light and high-porosity decoration waste as raw materials, making the surface of the sound barriers rough and porous, which is conducive to absorbing sound waves, and realizing high-quality utilization of decoration waste that is difficult to handle in construction waste. At the same time, the technical advantages of 3D printing are fully utilized to construct a sound-absorbing cavity that can be continuously printed in one piece. Combined with the surface stripe structure unique to 3D printing, a sound barrier with a sound-absorbing cavity and stripe structure that can be continuously printed on site or prefabricated in batches in a factory is designed and constructed, further enhancing the sound absorption characteristics, and solving the problems of the traditional cement single-plate cement sound barrier for noise reduction, unsatisfactory flowability, and poor noise reduction effect. The sound barrier has the advantages of free shape design, convenient and efficient construction, and can be applied to indoor or outdoor scenes where sound insulation is required, such as sound barriers on both sides of highways, sound barriers around construction sites, and sound barriers inside buildings.

[0040] Compared with the prior art, the present invention has the following characteristics:

[0041] 1) The present invention realizes high-quality utilization of decoration waste which is difficult to handle among construction waste, and at the same time fully utilizes the technical advantages of 3D printing to design and construct a sound barrier with sound-absorbing cavity and stripe structure, which can be continuously printed on site or prefabricated in batches in a factory;

[0042] 2) The present invention replaces the aggregate of cement-based 3D printing materials from natural sand and gravel with lightweight recycled aggregates from processed decoration waste, and forms a sound barrier through 3D printing, which is lighter in weight and has better sound insulation effect. In addition, these lightweight aggregates are recycled with high quality by preparing sound barriers. On the one hand, a large amount of solid waste that is difficult to recycle is consumed, and on the other hand, the lightweight and porous material characteristics of recycled aggregates from decoration waste are fully utilized, which is in line with the national circular economy concept;

[0043] 3) The present invention uses 3D printing technology to build a functional component such as a sound barrier, giving full play to the technical advantages of 3D printing. Compared with the previous 3D printed cement-based sound barriers, it adopts a unique structural design with a sound-absorbing cavity. On the premise of ensuring that continuous printing and construction using 3D printing technology is completely feasible, the sound insulation and noise reduction efficiency of the sound barrier is greatly enhanced;

[0044] 4) The 3D printed sound barrier of the present invention has the advantages of free appearance design and convenient and efficient construction. It can be applied to indoor or outdoor scenes where sound insulation is required, such as sound barriers on both sides of highways, sound barriers around construction sites, sound barriers inside buildings, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 The design and construction method of the 3D printed sound barrier based on the recycled materials of decoration waste in the present invention;

[0046] Figure 2 The physical principle of sound absorption and noise reduction of the unit cavity in the present invention;

[0047] Figure 3 It is the dimension design diagram of the unit cavity in the present invention;

[0048] Figure 4 is a schematic diagram of the structure of the unit cavity in Example 1;

[0049] Figure 5 is a schematic diagram of the structure of the unit cavity in Example 2;

[0050] Figure 6 The 3D printing path of the sound barrier body in Example 1;

[0051] Figure 7 The 3D printing path of the sound barrier base / top plate in Example 1;

[0052] Figure 8The 3D printing path of the sound barrier body in Example 2;

[0053] Fig. 9 The 3D printing path of the sound barrier base / top plate in Example 2;

[0054] Fig.10 It is a 3D model of the 3D printed sound barrier case based on recycled decoration waste in Example 1;

[0055] Fig.11 It is a 3D model of the 3D printed sound barrier case based on recycled decoration waste in Example 2;

[0056] Description of the markings in the figure:

[0057] a-unit cavity width, b-unit cavity length, d-channel width, x-channel position parameter, 2t-sound barrier body thickness, t-width of a single printed strip; 1-sound barrier body, 2-unit cavity, 3-sound absorption channel, 4-base, 5-top plate. DETAILED DESCRIPTION

[0058] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0059] The following are more detailed implementation cases, which further illustrate the technical solutions of the present invention and the technical effects that can be obtained.

[0060] In the following examples, unless otherwise specified, raw materials, reagents or processing techniques are all conventional commercial products or conventional processing techniques in the art.

[0061] In the following embodiments, the decoration waste lightweight aggregate comes from a construction waste resource recycling plant in Pudong New Area, Shanghai; the strength grade of ordinary Portland cement is PO 42.5 and above; and the nanoclay is nano attapulgite powder, 200 mesh.

[0062] Embodiment 1:

[0063] Figure 1 For the design and construction method of 3D printing sound barrier based on recycled decoration waste in this invention, we collected the crushed, sorted and screened decoration waste lightweight aggregates from a construction waste resource recycling plant in a certain place, of which the content of waste aerated blocks (waste aerated concrete blocks) was 87% (by volume, the same below), the content of waste wood was 5%, and the content of waste rubber was 8%. These lightweight aggregates have been screened, and their particle size is 0.15-2.36mm, and the density is 1000kg / m 3Below. According to the weight ratio, the formula of 3D printing "ink" material is designed as follows: 50 parts of lightweight aggregate from decoration waste, 100 parts of Portland cement, 35 parts of water, 1.3 parts of hydroxypropyl methylcellulose ether, 5.7 parts of nanoclay, 0.7 parts of sodium gluconate, and 0.7 parts of polycarboxylic acid water reducer.

[0064] The overall appearance model of the 3D printed sound barrier based on recycled decoration waste is as follows Fig.10 As shown, the preparation of the 3D printing material and the construction method of the 3D printing sound barrier specifically include the following steps:

[0065] 1) Add water to the lightweight aggregate of renovation waste and stir it in advance to make the aggregate fully absorb water and reach saturation;

[0066] 2) Then directly mix the decoration waste lightweight aggregate with cement and water, and use a forced mixer to stir for more than 90 seconds to ensure uniform mixing to obtain a mixture;

[0067] 3) adding hydroxypropyl methylcellulose ether, nanoclay and sodium gluconate to the uniformly stirred mixture, and continuing to stir to obtain a mixture;

[0068] 4) Then, the amount of polycarboxylate water reducer is determined according to the flow state of the mixture during stirring. In this process, the water reducer needs to be added several times until the fluidity of the mixture reaches about 180 mm to obtain the 3D printing "ink" material; when the mixture is thick, that is, the fluidity is less than 160 mm, the water reducer needs to be added to continue stirring, and the flow state is tested again, and so on, until the fluidity of the mixture reaches 180 mm; if the mixture is found to be too thin in the first test, that is, the fluidity is significantly greater than 200 mm, the formula is modified (the amount of water added is reduced) and re-prepared;

[0069] 5) After the 3D printing materials for building the sound barrier are prepared, the 3D printing materials are loaded into the silo of the 3D printer, the stirring screw of the 3D printer is turned on, and the printing status of the 3D printing materials is tested. When the 3D printing materials can be printed continuously without interruption and can be stably stacked without collapse or large deformation, the 3D printing materials can be printed continuously and can be stably stacked for construction;

[0070] 6) Input the pre-written printing path into the 3D printer, move the print head of the 3D printer to the origin, and start printing to obtain a 3D printed sound barrier with a channel-side unit cavity ( Fig.10 ).

[0071] like Fig.10As shown, the height of the sound barrier is 1.9m, the heights of the base 4 and the top plate 5 are 0.2m and 0.1m respectively, and the thickness of the sound barrier body 1 is 60mm. The higher the height of the sound barrier, the better the sound insulation effect. The sound barrier includes a sound barrier body 1, a plurality of unit cavities 2 arranged in parallel in the sound barrier body, a plurality of sound absorption channels 3 opened on one side of the sound barrier body 1 and connected to the corresponding unit cavities 2, a base 4 arranged at the bottom of the sound barrier body 1, and a top plate 5 arranged at the top of the sound barrier body, wherein the sound barrier body 1, the unit cavities 2, and the sound absorption channels 3 together constitute the sound barrier body of the sound barrier. Figure 6 This is the 3D printing path of the sound barrier body in this embodiment. Figure 7 3D printing paths of the base 4 and the top plate 5 in this embodiment. The base 4 and the top plate 5 are both provided with a plurality of through holes connected to the corresponding unit cavities 2. The base and the top plate 5 do not have sound absorption channels 3, but only cavities, that is, only a plurality of through holes connected to the corresponding unit cavities; the unit cavities 2 and the sound absorption channels 3 are respectively arranged to penetrate in the height direction. Figure 3 This is the size design drawing of the unit cavity 2 of the present invention, the unit cavity satisfies d / a<0.5, 0≤x≤ad, wherein a is the width of the unit cavity 2, b is the length of the unit cavity 2, d is the width of the sound absorption channel 3, x is the position parameter of the sound absorption channel 3, the width of the printed strip is t, and the thickness of the sound barrier body 1 is the width of the two printed strips, that is, the thickness of the sound barrier body 1 is 2t. Figure 4 is a schematic diagram of the structure of the unit cavity 2 in this embodiment, combined with Figure 6 and Figure 7 It can be seen that the cross section of the unit cavity 2 is square, and one side edge of the sound absorption channel 3 is flush with the side wall of the unit cavity 2, forming a channel side unit cavity ( Figure 4 ), satisfying x=ad, d / a<0.5, 0≤x≤ad, specifically: a=b=20cm, d=8cm, x=12cm, 2t=6cm. The sound barrier body 1 has a sound wave blocking effect. In order to give full play to the sound absorption function of the sound barrier cavity, all unit cavities 2 have a reserved sound absorption channel 3 for allowing external noise to enter multiple unit cavities 2. Figure 2 The physical principle of the sound absorption and noise reduction of the unit cavity 2 in the present invention is that the noise is reduced by 13-16 dB through the multiple absorption and reflection of sound waves by the inner wall of the cavity and the principle of sound wave interference inside the cavity.

[0072] Embodiment 2:

[0073] The difference between this embodiment and embodiment 1 is that the pre-written printing path is input into the 3D printer, the print head of the 3D printer is moved to the origin, and printing is started to obtain a 3D printed sound barrier with a channel-centered unit cavity ( Fig.11). The height of the sound barrier is 1.8m, the heights of the base 4 and the top plate 5 are 0.2m and 0.1m respectively, and the thickness of the sound barrier body 1 is 60mm. Figure 8 This is the 3D printing path of the sound barrier body in this embodiment. Fig. 9 The 3D printing path of the base 4 and the top plate 5 in this embodiment. The sound absorption channel 3 is arranged in the center of the unit cavity 2 along the width direction to form a channel-centered unit cavity ( Figure 5 ), x = (ad) / 2, d / a < 0.5, 0 ≤ x ≤ ad, specifically: a = b = 20 cm, d = 8 cm, x = 6 cm, 2t = 6 cm. The noise is reduced by 12 to 15 dB through the multiple absorption and reflection of the sound waves by the inner wall of the cavity and the principle of sound wave interference inside the cavity.

[0074] Comparative Example:

[0075] The only difference between this comparative example and Example 1 is that the lightweight aggregate of renovation waste is replaced with natural sand and gravel. The remaining steps are the same as those of Example 1. The obtained sound barrier can reduce noise by 7 to 9 dB.

[0076] In the above embodiment, the width a of the unit cavity 2 and the length b of the unit cavity 2 can be freely adjusted as required.

[0077] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A 3D printing material based on recycled decoration waste, characterized in that: The composition comprises the following components in parts by weight: The decoration waste lightweight aggregate is selected from at least one of waste aerated blocks, waste wood, waste rubber or waste plastic.

2. The 3D printing material based on recycled decoration waste according to claim 1 is characterized in that: The cement is ordinary Portland cement; the thickener is hydroxypropyl methylcellulose ether; the retarder is sodium gluconate; and the water reducer is a polycarboxylic acid-based water reducer.

3. The 3D printing material based on recycled decoration waste according to claim 1 is characterized in that: The density of the decoration waste lightweight aggregate is less than 1000kg / m 3 , particle size is 0.15-2.36mm, and fineness modulus is 2.2-2.8; in the lightweight aggregate of decoration waste, the volume proportion of the waste aerated blocks, waste wood or waste rubber is greater than 95%.

4. A method for preparing a 3D printing material according to any one of claims 1 to 4, characterized in that: The following steps are involved: 1) Add water to the decoration waste lightweight aggregate and stir it to make the decoration waste lightweight aggregate fully absorb water and reach a saturated state; 2) The fully water-absorbed lightweight aggregate of renovation waste is stirred and mixed with cement and water, and then a thickener, nanoclay, a retarder and a water reducing agent are added, and the stirring and mixing are continued to obtain the 3D printing material.

5. An application of the 3D printing material according to any one of claims 1 to 4 in 3D printing sound barriers, characterized in that: The 3D printing material is used to prepare a sound barrier.

6. The application of the 3D printing material in 3D printing sound barriers according to claim 5 is characterized in that: The sound barrier comprises a sound barrier body (1), a plurality of unit cavities (2) arranged in parallel in the sound barrier body, and a plurality of sound absorption channels (3) opened on one side of the sound barrier body (1) and connected to the corresponding unit cavities (2), wherein the unit cavities (2) and the sound absorption channels (3) are respectively arranged to penetrate along the height direction; the sound barrier also comprises a base (4) arranged at the bottom of the sound barrier body (1), and a top plate (5) arranged at the top of the sound barrier body, wherein the base (4) and the top plate (5) are both provided with a plurality of through holes connected to the corresponding unit cavities.

7. The use of the 3D printing material according to claim 5 in 3D printing sound barriers, characterized in that: The cross section of the unit cavity (2) is square, fan-shaped or trapezoidal; the sound absorption hole (3) is arranged in the center of the unit cavity (2) along the width direction; or, one side edge of the sound absorption hole (3) is flush with the side wall of the unit cavity (2).

8. The use of the 3D printing material according to claim 5 in 3D printing sound barriers, characterized in that: When the cross section of the unit cavity (2) is square, the width a of the unit cavity (2) and the width d of the sound absorption channel (3) satisfy the following relationship: d / a<0.5; the height of the 3D printed sound barrier is 1 to 5 m; the height of the base (4) and the top plate (5) is 0.1 to 0.5 m; and the thickness of the sound barrier body (1) is 40 to 80 mm.

9. The use of the 3D printing material according to claim 5 in 3D printing sound barriers, characterized in that: The preparation of the sound barrier comprises the following steps: S1: Load the 3D printing material into the silo of the 3D printer and start the stirring screw of the 3D printer; S2: Input a printing path into the 3D printer, move the print head of the 3D printer to the origin, start printing, and obtain the sound barrier.

10. The use of the 3D printing material according to claim 9 in 3D printing sound barriers, characterized in that: The 3D printer is a mortar / concrete 3D printer; the strip width of the printing of the 3D printer is 20-40 mm, the strip height is 10-20 mm, and the horizontal printing speed is 10-50 mm / s.

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