High-strength and high-damping concrete based on aggregate stacking structure and preparation method thereof

Abstract

The present invention relates to a high-strength, high-damping concrete based on an aggregate stacking structure and a preparation method thereof. The concrete is prepared by alternating layers of modified coarse aggregate and modified rubber particles and then pouring a modified cement grouting material. The raw materials of the modified coarse aggregate include 1300-1400 parts of coarse aggregate and 1.3-7 parts of a waterborne polyurethane emulsion by mass; the raw materials of the modified rubber particles include 88-220 parts of rubber particles and 4.4-33 parts of a waterborne epoxy resin emulsion; the raw materials of the modified cement grouting material include 250-320 parts of cement, 10-26 parts of silica fume, 75-130 parts of water, 5-15 parts of a waterborne acrylic emulsion, and 2.0-5.0 parts of a water reducer. The particle size of the coarse aggregate is larger than that of the rubber particles. The high-strength, high-damping concrete prepared by the present invention has substantially no strength loss compared to C50 ordinary concrete, while significantly increasing the damping ratio.

Description

Technical Field

[0001] The present invention relates to the field of concrete, and in particular to a high-strength and high-damping concrete based on an aggregate stacking structure and a preparation method thereof. Background Art

[0002] The low damping value of ordinary concrete restricts the dynamic performance of concrete structures. High-damping concrete improves the damping performance of concrete materials to improve their resistance to shocks such as earthquakes, wind vibrations, and mechanical vibrations. Current high-damping concrete is mainly polymer-modified concrete, which improves the deformation capacity and viscoelastic properties of concrete by utilizing the outstanding characteristics of the polymer itself, such as low elastic modulus, large deformation, and excellent viscoelasticity. In order to improve the damping performance of concrete, a very high amount of polymer emulsion is often required (up to 20-30% of the mass of the cementitious material). Although this brings about an improvement in the damping performance, it significantly reduces the strength of the concrete. Improving the damping performance of concrete while ensuring that the concrete has sufficient strength is of great engineering significance.

[0003] Chinese invention patent CN111087203 A discloses a method for preparing high-damping concrete. This invention improves the damping properties of concrete by introducing rubber powder. To address the negative impact of rubber powder on concrete strength, polypropylene fiber (0.5-1.5% by weight of cement) and microsilica fume (10% by weight of cement) are also added. Compared to ordinary concrete, the damping ratio of this high-damping concrete is increased from 2.22% to 4.72%, and the compressive strength is reduced from 27.1 MPa to 26.3 MPa. The high amounts of polypropylene fiber and microsilica fume used significantly increase material costs.

[0004] Chinese invention patent CN106242442 A discloses a method for preparing fiber-reinforced polymer concrete. This invention improves the damping properties of concrete by introducing a polymer emulsion comprising 7% to 16% of the cementitious material by weight. To address the mismatch between the mechanical and deformation properties of the concrete after the polymer emulsion is introduced, polyvinyl alcohol fibers modified with a silane coupling agent are introduced. This high-damping polymer concrete achieves a damping ratio of up to 7.5%, but the high amount of polymer emulsion used significantly increases material costs.

[0005] Chinese invention patent CN108249833 A discloses a high-damping concrete composite material and its preparation method. Drawing on the concept of constrained damping structures, this invention employs three functional layers: a constrained layer, a damping layer, and a structural layer. It also employs interface modification technology to achieve interface enhancement. Compared to conventional concrete, this high-damping concrete composite material increases its damping ratio from 0.9% to 4.60%, while reducing its compressive strength from 57.7 MPa to 52.3 MPa.

[0006] In summary, the current high damping concrete and its preparation method have the following problems:

[0007] (1) Existing technologies improve the damping properties of concrete by directly introducing rubber powder and polymer emulsion. This results in high material strength at low dosages, but no increase in damping value. At high dosages, the material has high damping value, but low strength and stiffness, resulting in insufficient structural bearing capacity, making it often unusable as a structural material. Furthermore, the large-scale use of polymer emulsion as a modifying component is expensive, increasing project costs. Therefore, the prominent issue in the design and preparation of high-damping concrete is resolving the conflict between material strength, damping, and cost.

[0008] (2) Improving the damping performance of concrete by adopting the design method of composite materials is an effective technical means, but the preparation process is complicated and time-consuming, and there are multiple interface composite problems, which will lead to the inability to fully exert the performance of the composite materials. Summary of the Invention

[0009] The purpose of the present invention is to overcome the above technical deficiencies, provide a high-strength and high-damping concrete based on an aggregate stacking structure and a preparation method, and solve the technical problem in the prior art that it is difficult to simultaneously take into account the strength and damping performance of high-damping concrete.

[0010] In order to achieve the above technical objectives, the technical solution provided by the present invention is:

[0011] In a first aspect, the present invention provides a high-strength and high-damping concrete based on an aggregate stacking structure, wherein the concrete is prepared by arranging modified coarse aggregate and modified rubber particles in layers in alternating order and then pouring modified cement grouting material into the layers; the raw materials of the modified coarse aggregate include, by weight, 1,300 to 1,400 parts of coarse aggregate and 1.3 to 7 parts of water-based polyurethane emulsion; the raw materials of the modified rubber particles include 88 to 220 parts of rubber particles and 4.4 to 33 parts of water-based epoxy resin emulsion; the raw materials of the modified cement grouting material include 250 to 320 parts of cement, 10 to 26 parts of silica fume, 75 to 130 parts of water, 5 to 15 parts of water-based acrylic emulsion, and 2.0 to 5.0 parts of water reducer; the particle size of the coarse aggregate is larger than the particle size of the rubber particles.

[0012] In a second aspect, the present invention provides a method for preparing high-strength and high-damping concrete based on an aggregate stacking structure, comprising the following steps: (1) first stacking a layer of modified coarse aggregate and then stacking a layer of modified rubber particles in a mold, and repeating the process several times to obtain an aggregate with a layered stacking structure; and (2) pouring a modified cement grouting material into the aggregate with the layered stacking structure, filling it densely, and curing it to obtain the high-strength and high-damping concrete.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] This invention employs alternating layers of modified coarse aggregate and modified rubber particles. The interlocking coarse aggregate ensures concrete strength and prevents floating of rubber particles during grouting. Furthermore, based on the principle of energy dissipation, modified rubber particles and a polymer emulsion-modified cement paste are introduced to enhance the concrete's damping properties. Coarse aggregate is the primary raw material, cement usage is minimal, and polymer emulsion usage is low, resulting in low cost. The high-strength, high-damping concrete produced using this invention exhibits no loss in strength compared to conventional C50 concrete, while significantly increasing the damping ratio. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic structural diagram of the high-strength and high-damping concrete obtained by the present invention. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0017] A high-strength and high-damping concrete based on an aggregate stacking structure comprises the following raw material components in parts by mass: 250-320 parts of cement, 10-26 parts of silica fume, 1300-1400 parts of coarse aggregate, 88-220 parts of rubber particles, 75-130 parts of water, 4.4-33 parts of water-based epoxy resin emulsion, 1.3-7 parts of water-based polyurethane emulsion, 5-15 parts of water-based acrylic emulsion, and 2.0-5.0 parts of a water reducer.

[0018] Preferably, the raw materials include: 260-300 parts of cement, 15-22 parts of silica fume, 1300-1400 parts of coarse aggregate, 88-220 parts of rubber particles, 80-120 parts of water, 8.8-22 parts of water-based epoxy resin, 6-7 parts of water-based polyurethane, 5-12 parts of water-based acrylic acid, and 2.5-5.0 parts of water reducer.

[0019] Preferably, the cement is ordinary Portland cement, Portland cement or sulphoaluminate cement with a strength grade of 42.5 or above;

[0020] Preferably, the specific surface area of ​​the silica fume is greater than 21m 2 / g.

[0021] Preferably, the coarse aggregate is granite aggregate with a diameter of 16 to 25 mm.

[0022] Preferably, the rubber is waste rubber with a particle size of 5 to 10 mm.

[0023] Preferably, the solid content of the waterborne epoxy resin emulsion is 20-40%, and a non-ionic bisphenol A epoxy resin is selected, and its epoxy equivalent is 420-1000; more preferably, the GEM03 waterborne epoxy resin produced by Shanghai Lujia Industrial Co., Ltd.

[0024] Preferably, the solid content of the aqueous polyurethane emulsion is 20-40%, the tensile strength of the aqueous polyurethane film is 20-50 MPa, and the elongation at break is 400-700%. More preferably, LP-855A from Henan Mingcheng Chemical Products Co., Ltd. is used.

[0025] For the waterborne polyurethane film test, the waterborne polyurethane emulsion is poured into a dumbbell-shaped mold treated with a fluorine-based release agent. The surface is then scraped to ensure a final coating thickness of 1.5 ± 0.2 mm. Five samples are tested in each group. The total length of the film stretching dumbbell-shaped sample is 115 mm, with a total length of 33 mm and a width of 6 mm at the narrow section.

[0026] Preferably, the solid content of the aqueous acrylic emulsion is 20-40%, and pure acrylic, styrene or silicone-modified acrylic emulsion is selected; more preferably, the aqueous acrylic emulsion is from Henan Taiji Chemical Products Co., Ltd.

[0027] Preferably, the water reducer is a polycarboxylic acid water reducer with a solid content of 25-30% and a water reduction rate of 30-35%.

[0028] A method for preparing high-strength and high-damping concrete based on an aggregate stacking structure comprises the following steps:

[0029] (1) uniformly mixing the aqueous polyurethane emulsion and the coarse aggregate and air-drying the mixture to form a film, thereby obtaining a modified coarse aggregate coated with the aqueous polyurethane emulsion;

[0030] The waterborne epoxy resin emulsion and rubber particles are mixed evenly and air-dried to form a film to obtain modified rubber particles coated with the waterborne epoxy resin;

[0031] A layer of modified coarse aggregate is pre-stacked in the mold, followed by a layer of modified rubber particles; this is repeated until the mold is fully filled. There is little difference between using modified coarse aggregate or modified rubber particles for the top layer. For ease of description, the following embodiments all take the modified coarse aggregate as the top layer as an example.

[0032] (2) uniformly mixing cement, silica fume, water, water-based acrylic emulsion and water reducing agent to obtain a high-fluidity water-based acrylic emulsion modified cement grouting material;

[0033] The modified cement grouting material is poured into the mold of step (1) under vibration forming, the mold is filled densely, and high-strength and high-damping concrete is obtained through curing.

[0034] See also Figure 1 The high-strength and high-damping concrete obtained by the present invention includes modified coarse aggregate layers and modified rubber particle layers that are alternately arranged in layers. Through vibration molding, the modified cement grouting material enters the gaps between the modified coarse aggregate layers and the modified rubber particle layers and fills them densely.

[0035] Preferably, the polymer emulsion is used to wrap aggregate or rubber particles, and the preparation method is as follows: aggregate or rubber particles of selected grade are added to a mixer, an aqueous polyurethane emulsion with a mass of 0.1 to 0.5 wt% of the aggregate mass is selected to treat the ordinary aggregate, and an aqueous epoxy resin emulsion with a mass of 5 to 15 wt% of the rubber mass is selected to treat the rubber particles, and the mixture is uniformly stirred for 3 to 10 minutes. During the stirring process, a defoaming agent (capable of defoaming, of which there are many types, such as silicone or polyether defoaming agents, which are not specifically limited here) is added at a mass of 0.01 to 0.05 wt% of the solid content of the polymer emulsion. Subsequently, the aggregate or rubber particles are removed and cured at room temperature for 24 hours until the polymer emulsion breaks and forms a film, thereby obtaining modified coarse aggregate or modified rubber particles.

[0036] Preferably, the high-fluidity water-based acrylic modified cement grouting material has a composition of cement: silica fume: water: water-based acrylic emulsion: water reducer: 1: (0.04-0.08): (0.3-0.4): (0.02-0.04): (0.008-0.015), and the mortar expansion is 350-400 mm.

[0037] Preferably, the curing is carried out at a temperature of 10 to 30° C. and a relative humidity of 50 to 80% for 12 to 48 hours, followed by demoulding, and then curing for more than 20 days at a temperature of 10 to 30° C. and a relative humidity of more than 90%.

[0038] The main mechanism of action of the present invention:

[0039] 1. The use of pre-set aggregate technology to prepare concrete can significantly increase the volume fraction of aggregate used, give full play to the interlocking and skeletal effects of aggregate, and ensure structural rigidity and elastic modulus. The addition of rubber particles can effectively improve the damping ratio of concrete, but directly adding rubber particles to cement concrete often leads to a reduction in strength. The present invention fills large-particle coarse aggregate with small-particle rubber aggregate, which not only alleviates the stress concentration of rigid aggregate during loading, but also further dissipates energy, improves the damping performance of concrete, and solves the problem that the addition of rubber powder in the past affects the strength of cement concrete.

[0040] 2. In terms of aggregate material selection, solid granite aggregate is selected; through the optimization of aggregate particle size, coarse aggregate with particle size of 16-20mm and rubber particles with particle size of 5-10mm are compounded in a certain volume ratio, and the coarse aggregate is interlocked to suppress the floating of rubber particles during the grouting process, thereby maintaining a good composite structure.

[0041] 3. As the aggregate volume fraction increases, the number of interfacial transition zones in concrete increases. By pre-treating the coarse aggregate with a highly viscoelastic water-based polyurethane emulsion, its tensile strength can reach 20-50 MPa and its elongation at break can reach 400-700%. Applying this emulsion to the interfacial transition zone, the weakest part of concrete, can help resist crack propagation and alleviate stress concentration. Simultaneously, introducing a small amount of water-based acrylic emulsion into the cement grout—a water-based polyacrylic resin with excellent tensile strength, elongation at break, impact resistance, and bonding ability—can achieve dual energy dissipation by modifying the cement paste microstructure and the interfacial transition zone, further improving the damping properties of cement concrete.

[0042] 4. Using a water-based epoxy resin film to treat waste rubber particles, the high bonding strength of water-based epoxy resin is utilized to strengthen the interface transition zone between rubber particles and cement stone, thereby improving the compressive strength of cement concrete. At the same time, the use of waste rubber particles has good economic and environmental benefits.

[0043] The present invention is further described in detail below through specific examples.

[0044] Example 1

[0045] A method for preparing high-strength and high-damping concrete based on aggregate stacking structure design, comprising the following steps:

[0046] (1) Aggregate pretreatment: The materials were collected at a volume ratio of 1:0.35 between coarse aggregate and rubber particles. Granite coarse aggregate with a particle size of 16 to 25 mm and rubber particles with a particle size of 5 to 10 mm were cleaned and placed in a mixer. Ordinary aggregate was treated with a water-based polyurethane emulsion containing 0.5 wt% of aggregate and 40% of emulsion solids. Rubber particles were treated with a water-based epoxy resin containing 10 wt% of waste rubber particles and 40% of emulsion solids. The mixture was stirred for 3 minutes. During the stirring process, a defoamer accounting for 0.05 wt% of the polymer emulsion solids was added. The mixture was taken out and air-dried to form a film of the polymer emulsion on the surface of the coarse aggregate. Modified coarse aggregate and modified rubber particles were obtained to prepare concrete.

[0047] (2) Pre-filling the mold with coarse aggregate: Pre-pile a layer of modified coarse aggregate in the mold, then pile up a layer of modified rubber particles, and repeat this process until the mold is fully filled.

[0048] (3) Grouting: First, stir the cement and silica fume for 2 minutes. After stirring evenly, add water mixed with a water-reducing agent and a water-based acrylic emulsion and stir for 3 minutes. Pour the above cement slurry into the mold under vibration molding. Fill it tightly. After curing at 20±2℃ and a relative humidity of 60%±5% for one day, demould it, and then cure it at 20±2℃ and a relative humidity of >95% for 28 days to obtain high-strength and high-damping concrete.

[0049] Comparative Example 1

[0050] The preparation method of ordinary C50 concrete is as follows:

[0051] Add the selected mass of cement, silica fume, and coarse aggregate to a mixer and mix for 3 minutes. Once uniformly mixed, add water with a water reducer and mix thoroughly. Pour the mixed slurry into a mold under vibration. Curing at 20±2°C and a relative humidity of 60%±5% for one day, remove from the mold, and then cure at 20±2°C and a relative humidity greater than 95% for 28 days to obtain conventional molded C50 concrete.

[0052] Comparative Example 2

[0053] A method for preparing high-strength and high-damping concrete based on aggregate stacking structure design, comprising the following steps:

[0054] (1) Pre-filling the mold with coarse aggregate: clean the granite aggregate with a particle size of 16 to 25 mm and loosely pile it in the mold;

[0055] (2) Grouting: First, mix the cement and silica fume for 2 minutes. After mixing evenly, add water mixed with a water reducer and stir for 3 minutes. Pour the above cement slurry into the mold under vibration molding. Fill it tightly. After curing at 20±2℃ and relative humidity of 60%±5% for one day, demould it, and then cure it at 20±2℃ and relative humidity>95% for 28 days to obtain pre-set aggregate molded concrete.

[0056] Comparative Example 3

[0057] A method for preparing high-strength and high-damping concrete based on aggregate stacking structure design, comprising the following steps:

[0058] (1) Pre-filling the mold with coarse aggregate: After cleaning the granite aggregate with a particle size of 16 to 25 mm and the rubber particles with a particle size of 5 to 10 mm, loosely pile them up in sequence to fill the mold, first piling up a layer of granite aggregate and then piling up a layer of rubber particles. The volume ratio of granite aggregate to rubber particles is 1:0.2.

[0059] (2) Grouting: First, mix the cement and silica fume for 2 minutes. After mixing evenly, add water mixed with a water reducer and stir for 3 minutes. Pour the above cement slurry into the mold under vibration molding. Fill it tightly. After curing at 20±2℃ and relative humidity of 60%±5% for one day, demould it. Then, cure it at 20±2℃ and relative humidity>95% for 28 days to obtain high-strength and high-damping concrete.

[0060] Comparative Example 4

[0061] A method for preparing high-strength and high-damping concrete based on aggregate stacking structure design, comprising the following steps:

[0062] (1) Pre-filling the mold with coarse aggregate: After cleaning the granite aggregate with a particle size of 16 to 25 mm and the rubber particles with a particle size of 5 to 10 mm, loosely pile them up in sequence to fill the mold, first piling up a layer of granite aggregate and then piling up a layer of rubber particles. The volume ratio of granite aggregate to rubber particles is 1:0.5.

[0063] (2) Grouting: First, mix the cement and silica fume for 2 minutes. After mixing evenly, add water mixed with a water reducer and stir for 3 minutes. Pour the above cement slurry into the mold under vibration molding. Fill it tightly. After curing at 20±2℃ and relative humidity of 60%±5% for one day, demould it. Then, cure it at 20±2℃ and relative humidity>95% for 28 days to obtain high-strength and high-damping concrete.

[0064] In a specific embodiment, the compressive strength and elastic modulus of concrete were tested in accordance with GB / T50081-2019, "Standard for Test Methods for Physical and Mechanical Properties of Concrete." Testing was performed using the free decay method, and the damping ratio was used to characterize the damping performance of the concrete. The formulations for the above-described embodiments and comparative examples are shown in Table 1 below, and the test results are shown in Table 2 below. (Compressive strength: 150 mm cube specimen; elastic modulus: 150 mm * 150 mm * 300 mm prism specimen).

[0065] Table 1: Formulas of concrete products described in comparative examples and examples (parts by weight):

[0066]

[0067]

[0068] Table 2 Performance test results of the concrete products described in the comparative examples and examples:

[0069]

[0070] As can be seen from Tables 1 and 2, in Comparative Example 2, the molding process is changed on the basis of Comparative Example 1, which can effectively improve the compressive strength of the obtained concrete, but the improvement of the damping ratio is not obvious; in Comparative Example 3, rubber particles are added, and although the damping ratio is improved, the effect is limited; in Comparative Example 4, by increasing the amount of rubber particles, the damping ratio is greatly improved, but the compressive strength is significantly reduced.

[0071] In Example 1, modified coarse aggregate, modified rubber and modified cement grouting material are used in conjunction with the aggregate stacking structure forming process. While reducing cement consumption and reducing costs, the strength of the resulting concrete is comparable to that of C50 ordinary concrete, and the damping ratio is significantly increased.

[0072] Example 2-3:

[0073] The only difference between Examples 2 and 3 and Example 1 is that the volume ratio of the added rubber particles is adjusted. Other steps and conditions are the same as those in Example 1. The specific ratios and the resulting concrete properties are shown in Table 3 below.

[0074] Table 3 Raw material ratios and concrete properties of Examples 2-3

[0075] serial number Modified coarse aggregate: modified rubber (volume ratio) 28d compressive strength / MPa 28d damping ratio / % Example 1 1：0.35 51.52 5.70 Example 2 1：0.2 52.33 5.38 Example 3 1：0.5 49.56 5.92

[0076] As can be seen from Table 3 above, adding too much rubber particles will lead to a decrease in the compressive strength of the concrete, while adding too little will reduce the damping ratio of the concrete. Therefore, the present invention preferably has a volume ratio of coarse aggregate to rubber particles of 1: (0.2-0.5).

[0077] Comparative Example 5

[0078] The only difference between Comparative Example 5 and Example 1 is that the molding processes are different. In Comparative Example 5, the raw materials used above are directly mixed according to the ordinary concrete molding method. The other steps and conditions are the same as those in Example 1. The properties of the obtained concrete are shown in Table 4 below:

[0079] Table 4 Concrete performance results obtained in Example 1 and Comparative Example 5

[0080] serial number Molding method 28d compressive strength / MPa 28d damping ratio / % Example 1 Pre-placed aggregate forming 51.52 5.70 Comparative Example 5 Ordinary stirring molding 45.38 5.19

[0081] As can be seen from Table 4 above, changing the molding method cannot form the uniform aggregate stacking structure of the present invention, resulting in a significant decrease in compressive strength and damping ratio.

[0082] Other factors affecting the present invention:

[0083] (1) In the grouting material, a high amount of silica fume results in a viscous slurry, while a low amount results in poor slurry fluidity. Therefore, a cement: silica fume mass ratio of 1: (0.04-0.08) is selected, and a more preferred ratio is 1:0.06. A high amount of water-based acrylic acid reduces slurry strength and increases cost. Therefore, a cement: water-based acrylic emulsion mass ratio of 1: (0.02-0.04) is selected, and a more preferred ratio is 1:0.02. After the water-based acrylic emulsion is added to the slurry, it can increase the slurry fluidity, thereby reducing the amount of water reducer.

[0084] (2) Using 0.1-0.5 wt% of waterborne polyurethane to treat coarse aggregate, too high a dosage (more than 0.5 wt%) will weaken the interface transition zone and have a negative impact on strength; using 5-15 wt% of waterborne epoxy resin to treat rubber particles, too high a dosage will increase the cost, and too low a dosage will lead to poor enhanced interface bonding effect.

[0085] In summary, the present invention provides a high-strength, high-damping concrete, the components and their weight percentages of which are as follows: 250-320 parts of cement, 10-26 parts of silica fume, 1300-1400 parts of coarse aggregate, 88-220 parts of rubber particles, 75-130 parts of water, 4.4-33 parts of water-based epoxy resin emulsion, 1.3-7 parts of water-based polyurethane emulsion, 5-15 parts of water-based acrylic emulsion, and 2.0-5.0 parts of water reducer. The method for preparing the high-strength, high-damping concrete comprises the following steps: ① Pre-stack a layer of ordinary crushed stone aggregate coated with water-based polyurethane emulsion in a mold, and then stack a layer of waste rubber particles coated with water-based epoxy resin; repeat the steps in sequence until the mold is filled. ② Pour high-fluidity water-based acrylic emulsion-modified cement grouting material under vibration molding, fill the mold densely, and obtain high-strength, high-damping concrete. The present invention ensures the strength of the concrete by interlocking the coarse aggregate and avoids the floating of rubber particles during the grouting process. Based on the principle of energy dissipation, rubber particles and polymer emulsion are introduced to modify the cement paste to improve the damping performance of the concrete. The high-strength, high-damping concrete prepared using this method has essentially no loss in strength compared to ordinary C50 concrete, while significantly increasing the damping ratio.

[0086] The high-strength and high-damping concrete prepared by the present invention has a 28d compressive strength of 49.56-51.52 MPa and a damping ratio of 5.38-5.92%. Compared with ordinary concrete, the damping ratio is greatly improved without reducing the mechanical properties.

[0087] The specific embodiments of the present invention described above do not limit the scope of protection of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A method for preparing high-strength and high-damping concrete based on an aggregate stacking structure, characterized in that: The following steps are involved: (1) First, a layer of modified coarse aggregate is piled up in the mold, and then a layer of modified rubber particles is piled up. This process is repeated several times to obtain a layered aggregate structure. (2) pouring the modified cement grouting material into the aggregate of the layered stacking structure, filling it densely, and curing it to obtain the high-strength and high-damping concrete; By mass, The raw materials of the modified coarse aggregate include 1300-1400 parts of coarse aggregate and 1.3-7 parts of waterborne polyurethane emulsion; The raw materials of the modified rubber particles include 88 to 220 parts of rubber particles and 4.4 to 33 parts of waterborne epoxy resin emulsion; The raw materials of the modified cement grouting material include 250-320 parts of cement, 10-26 parts of silica fume, 75-130 parts of water, 5-15 parts of water-based acrylic emulsion, and 2.0-5.0 parts of water reducing agent; The modified coarse aggregate is obtained by uniformly mixing the coarse aggregate with an aqueous polyurethane emulsion accounting for 0.1 to 0.5% of the mass of the coarse aggregate, and then air-drying to form a film; the modified rubber particles are obtained by uniformly mixing the rubber particles with an aqueous epoxy resin emulsion accounting for 5 to 15% of the mass of the rubber particles, and then air-drying to form a film; During the preparation of the modified coarse aggregate and the modified rubber particles, a defoamer accounting for 0.01 to 0.05 wt% of the waterborne polyurethane emulsion or the waterborne epoxy resin emulsion is added respectively; The coarse aggregate is granite aggregate with a diameter of 16 to 25 mm; the rubber particles are waste rubber with a diameter of 5 to 10 mm.

2. The method for preparing high-strength and high-damping concrete based on an aggregate stacking structure according to claim 1, characterized in that: The cement is ordinary Portland cement, Portland cement or sulphoaluminate cement with a strength grade of 42.5 or above.

3. The method for preparing high-strength and high-damping concrete based on an aggregate stacking structure according to claim 1, characterized in that: The specific surface area of ​​the silica fume is greater than 21m 2 / g.

4. The method for preparing high-strength and high-damping concrete based on an aggregate stacking structure according to claim 1, characterized in that: The solid contents of the aqueous polyurethane emulsion, aqueous epoxy resin emulsion and aqueous acrylic emulsion are all 20-40%.

5. The method for preparing high-strength and high-damping concrete based on aggregate stacking structure according to claim 1, characterized in that: The water reducer is a polycarboxylic acid water reducer with a solid content of 25-30% and a water reduction rate of 30-35%.

6. The method for preparing high-strength and high-damping concrete based on an aggregate stacking structure according to claim 1, characterized in that: The modified cement grouting material is prepared by mixing cement, silica fume, water, water-based acrylic emulsion and water reducing agent in a mass ratio of 1: (0.04-0.08): (0.3-0.4): (0.02-0.04): (0.008-0.015).

7. High-strength and high-damping concrete based on an aggregate stacking structure obtained by the preparation method according to any one of claims 1 to 6.

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