A skeleton grouting type porous noise reduction concrete pavement material and a preparation method thereof

Abstract

This invention discloses a skeleton-grouted porous noise-reducing concrete pavement material and its preparation method. The method involves hardening macroporous concrete to form a skeleton structure, followed by high-pressure grouting to inject polymer-modified cement-based porous grout into the macroporous concrete skeleton structure, forming a composite structural system with macroporous concrete as the skeleton and polymer-modified cement-based porous grout as the filler. The macroporous concrete skeleton provides sufficient strength, while the polymer-modified cement-based porous grout, with its numerous interconnected and complex pore structures, exhibits excellent sound absorption and noise reduction while protecting the aggregate particles of the macroporous concrete skeleton from detachment, thus improving durability. This pavement material has a rational structural combination, fully utilizing the characteristics of both the macroporous concrete skeleton and the polymer-modified cement-based porous grout, ensuring both road performance and noise reduction functionality.

Description

Technical Field

[0001] This invention belongs to the technical field of road engineering noise reduction pavement materials, and relates to a skeleton grouting type sound-absorbing and noise-reducing concrete pavement material and its preparation method. Background Technology

[0002] Noise pollution caused by modern transportation is a widely concerned technical problem. The harm and impact of noise pollution on people's physical and mental health cannot be ignored. Daytime noise limits of 55 dB and nighttime noise limits of 45 dB are set for residential areas, medical and health facilities, and cultural and educational areas; daytime noise limits of 70 dB and nighttime noise limits of 55 dB are set for high-grade highways, first and second-class highways, and urban secondary arterial roads and above. Road surface noise, as a type of noise pollution caused by transportation, is positively correlated with vehicle speed. For example, residential areas and office buildings along urban expressways suffer from severe noise pollution problems. Surveys show that noise levels exceeding 40-50 dB generally interfere with normal sleep, 60-70 dB seriously affect learning, and levels above 120 dB can cause varying degrees of damage to the auditory system. Furthermore, on highways where vehicles travel at high speeds, road surface noise has a negative impact on the psychological and physiological health of drivers and passengers. Especially in long tunnels, road surface noise undergoes multiple reflections, resonances, and superpositions, resulting in a dramatic increase in noise levels. Drivers exposed to high-noise environments for extended periods are highly susceptible to fatigue, anxiety, and difficulty concentrating. Traditional sound barriers are not only inconvenient to install and space-consuming, with limited noise reduction effects, but they also fail to fundamentally solve the problem of road noise. The ideal solution is to provide a road material that meets both road surface technical performance requirements and noise reduction functions, thereby fundamentally reducing or even eliminating road noise.

[0003] Noise-reducing pavements have become a hot topic in road engineering materials research, with commonly used noise-reducing pavements mostly utilizing porous concrete and open-graded asphalt mixtures (OGFC). While the interconnected pores within porous materials can absorb noise to some extent, the sound absorption capacity of traditional porous pavement materials is limited. First, unconnected voids in the pavement structure create a "horn effect"; second, relatively simple and large interconnected pores create a "whistle effect." Therefore, the noise absorption effect of traditional porous pavement materials is not ideal. Furthermore, traditional porous pavement materials generally suffer from low strength, aggregate particle stripping, and poor durability, thus limiting their application scope. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a skeleton-grouted porous noise-reducing concrete pavement material and its preparation method, thereby solving the problems of poor noise reduction effect and limited application range of existing pavement materials.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A method for preparing a skeleton-grouted porous noise-reducing concrete pavement material includes the following steps:

[0007] Step 1, Preparation of large-pore skeleton concrete:

[0008] Step 1.1: Weigh the following components: cement, mineral powder, crushed stone coarse aggregate, water-reducing agent, and water;

[0009] Step 1.2, Mixing: First, mix the cement and mineral powder evenly, and dissolve the water-reducing agent in water and mix evenly. Then, dry mix the crushed stone coarse aggregate with the cement-mineral powder mixture, add 50% of the water-water-reducing agent mixture and stir. Finally, add the remaining water-water-reducing agent mixture and continue stirring to form a uniform and stable concrete mixture.

[0010] Step 1.3, Pouring and Shaping: Pour the concrete mixture into the set template and smooth the surface.

[0011] Step 1.4, Curing: The large-pore concrete skeleton poured and formed in Step 1.3 shall be cured for 3 to 7 days; the formwork shall not be removed and the process shall proceed to the next step.

[0012] Step 2, Preparation of polymer-modified cement-based porous grouting material:

[0013] Step 2.1, weigh the following components: cement, rubber powder, polyurethane powder, aluminum powder, foaming agent, tackifier, water-reducing agent, and water;

[0014] Step 2.2, Mixing: Mix cement, rubber powder and aluminum powder evenly, dissolve water-reducing agent in water, then dry mix polyurethane fragments with cement-rubber powder-aluminum powder mixture, then add 50% water-water-reducing agent mixture and stir, then add the remaining water-water-reducing agent mixture and stir, finally add foaming agent and thickener and stir at high speed to form a uniform and stable concrete mixture.

[0015] Step 3, prepare skeleton-grouted porous noise-reducing concrete:

[0016] Step 3.1, Grouting: The concrete mixture obtained in Step 2 is injected into the large-pore concrete skeleton structure obtained in Step 1 through a high-pressure grouting device. The grouting volume is controlled by the design porosity and the actual grouting pressure to ensure that the internal interconnected pores are completely filled by the grouting material.

[0017] Step 3.2, Curing: Smooth the surface of the grouting skeleton structure after grouting, remove the formwork and clean up the excess grout around it, and then cover it with plastic wrap for curing. The curing period is 28 days to obtain the skeleton grouting type porous noise reduction concrete pavement material.

[0018] The present invention also includes the following technical features:

[0019] Specifically, in step 1.1, the components are as follows by mass percentage: cement 10%–18%, mineral powder 5%–10%, crushed stone coarse aggregate 65%–72%, water-reducing agent 1%–1.5%, and water 7.5%–10%; the sum of the mass percentages of each component is 100%.

[0020] Specifically, in step 1.1, the cement is P·O 42.5 ordinary Portland cement or P·O 52.5 ordinary Portland cement;

[0021] The ore powder is S95 grade granulated blast furnace slag powder or S105 grade granulated blast furnace slag powder;

[0022] The coarse aggregate of the crushed stone is basalt crushed stone or granite crushed stone with a particle size of 16-26mm;

[0023] The water-reducing agent is a polycarboxylate high-efficiency water-reducing agent.

[0024] Specifically, in step 1.2, the dry mixing time of the crushed stone coarse aggregate and the cement-mineral powder mixture is 1 to 2 minutes; the mixing time of adding 50% of the water-water-reducing agent mixture is 1.5 to 3 minutes; and the mixing time of adding the remaining water-water-reducing agent mixture is 2 to 3 minutes.

[0025] Specifically, in step 2.1, the components, by mass percentage, are: cement 45%–50%, rubber powder 10%–20%, polyurethane fragments 8%–12%, aluminum powder 6%–10%, foaming agent 3.5%–5%, tackifier 1%–1.5%, water-reducing agent 1%–1.5%, and water 10%–15%; the sum of the mass percentages of all components is 100%.

[0026] Specifically, in step 2.1, the cement is P·O32.5 ordinary Portland cement, P·O42.5 ordinary Portland cement, or CA60-II sulfoaluminate cement;

[0027] The rubber powder is 40-60 mesh.

[0028] The particle size of polyurethane fragments should not exceed 5mm;

[0029] The aluminum powder is either atomized spherical aluminum powder or high-spherical micro-fine aluminum powder;

[0030] The foaming agent is sodium dodecyl sulfate, sodium rosinate, or α-ammonium alpha-sulfate;

[0031] The tackifier is a warm-rolled cement tackifier, a cellulose ether tackifier, or polyethylene oxide;

[0032] The water-reducing agent is a polycarboxylate high-efficiency water-reducing agent.

[0033] Specifically, in step 2.2, the dry mixing time of polyurethane granules and cement-rubber powder-aluminum powder mixture is 2-3 minutes; the mixing time of adding 50% water-water-reducing agent mixture is 1.5-2.5 minutes; the mixing time of adding the remaining water-water-reducing agent mixture is 2-3 minutes; and the mixing time of adding foaming agent and tackifier and high-speed mixing is 1.5-3 minutes.

[0034] Specifically, the high-speed stirring speed is greater than 1000 rad / min.

[0035] Specifically, in step 3.1, grouting is stopped when the grouting volume of the high-pressure grouting equipment reaches 30% to 35% of the volume of the large-pore concrete skeleton and the grouting pressure reaches 2.5 MPa or higher.

[0036] A skeleton-grouted porous noise-reducing concrete pavement material is prepared by the aforementioned method for preparing skeleton-grouted porous noise-reducing concrete pavement material.

[0037] Compared with the prior art, the present invention has the following technical effects:

[0038] 1) The skeleton-filled porous noise-reducing concrete pavement material of the present invention belongs to a novel skeleton-filled concrete structure. Large-particle-size, large-pore porous concrete has higher strength, and the formed skeleton can provide sufficient support for the structure, giving it higher mechanical strength, which can meet the application requirements of most road engineering projects, such as highways and urban expressways.

[0039] 2) This invention utilizes high-pressure grouting to fill the interconnected pores with porous cement grout material that has even finer and more complex pores. On one hand, the grout material forms a structural whole with the large-pore framework concrete, reinforcing the structure. On the other hand, it optimizes the surface texture of the road surface, providing anti-skid and noise reduction functions while effectively preventing aggregate particle shedding.

[0040] 3) The sound absorption and noise reduction capabilities of porous materials are not only related to their porosity, but more importantly, to their pore structure. A connected and complex pore structure has a better noise reduction effect. The polymer-modified cement-based porous grouting material of this invention draws on the principle of foamed concrete, resulting in a large number of uniform pores within the grouting material. However, the bubbles formed by conventional foamed concrete are relatively closed and cannot form a connected pore structure, which is not beneficial for noise reduction. Therefore, aluminum powder is introduced into the raw materials of this invention. Aluminum powder is beneficial to the hydration reaction, contributing to the strength of the hardened grouting material. Furthermore, as the hydration reaction proceeds, aluminum powder can react with the hydration product calcium hydroxide to generate hydrogen gas. The generation of hydrogen gas can cause the bubbles generated by the foaming agent to break and connect, forming a connected open pore structure. This open pore structure is characterized by its large quantity, interconnectedness, and complexity. Therefore, it can greatly improve the sound absorption and noise reduction function while maintaining the permeability of the structure.

[0041] 4) In the grouting material of the present invention, polyurethane fragments are lightweight, porous and deformable. The filler structure formed after addition makes the pore structure more complex and has certain sound absorption characteristics. Therefore, the introduction of polyurethane fragments further improves the sound absorption and noise reduction performance.

[0042] 5) This invention adopts a secondary processing construction process, which can effectively avoid the decline in project quality caused by the discreteness of concrete construction. First, a high-quality and stable large-pore porous concrete skeleton structure is formed through mature porous concrete construction technology. Then, a stable grouting material is prepared and pressed into the skeleton structure using high-pressure equipment. By designing construction parameters such as porosity and grouting pressure to control the grouting volume, the quality of the product of this invention can be guaranteed. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of a large-pore concrete skeleton structure.

[0044] Figure 2 A schematic diagram of a skeleton-type porous noise-reducing concrete pavement material formed by injecting polymer-modified cement-based porous grouting material;

[0045] Figure 3 This is a comparison chart of sound absorption coefficient effects. Detailed Implementation

[0046] This invention provides a skeleton-grouted porous noise-reducing concrete pavement material, comprising a macroporous concrete skeleton structure, a polymer-modified cement-based porous grout, and a preparation method thereof. The skeleton-grouted porous noise-reducing concrete is formed by hardening macroporous concrete to create a skeleton structure, and then injecting polymer-modified cement-based porous grout into the macroporous concrete skeleton structure via high-pressure grouting, forming a composite structural system with macroporous concrete as the skeleton and polymer-modified cement-based porous grout as the filler. Its advantages lie in the fact that the macroporous concrete skeleton provides sufficient strength, while the polymer-modified cement-based porous grout, with its numerous interconnected and complex pore structures, exhibits excellent sound absorption and noise reduction functions while protecting the aggregate particles of the macroporous concrete skeleton from detachment, thereby improving durability. This pavement material has a rational structural combination, fully utilizing the characteristics of the macroporous concrete skeleton and the polymer-modified cement-based porous grout, ensuring the simultaneous achievement of road performance and noise reduction functions.

[0047] Specifically, the following steps are included:

[0048] Step 1, Preparation of large-pore skeleton concrete:

[0049] Step 1.1: Weigh the following components: cement, mineral powder, crushed stone coarse aggregate, water-reducing agent, and water;

[0050] Specifically, in step 1.1, the components, by mass percentage, are: cement 10%–18%, mineral powder 5%–10%, crushed stone coarse aggregate 65%–72%, water-reducing agent 1%–1.5%, and water 7.5%–10%; the sum of the mass percentages of all components is 100%. The cement is P·O42.5 ordinary Portland cement or P·O52.5 ordinary Portland cement; the crushed stone coarse aggregate is basalt crushed stone or granite crushed stone with a particle size of 16–26 mm; the water-reducing agent is polycarboxylate high-efficiency water-reducing agent.

[0051] Step 1.2, Mixing: First, mix the cement and mineral powder evenly, and dissolve the water-reducing agent in water and mix evenly. Then, dry mix the crushed stone coarse aggregate with the cement-mineral powder mixture, add 50% of the water-water-reducing agent mixture and stir. Finally, add the remaining water-water-reducing agent mixture and continue stirring to form a uniform and stable concrete mixture.

[0052] Specifically, in step 1.2, the dry mixing time of the crushed stone coarse aggregate and the cement-mineral powder mixture is 1 to 2 minutes; the mixing time of adding 50% of the water-water-reducing agent mixture is 1.5 to 3 minutes; and the mixing time of adding the remaining water-water-reducing agent mixture is 2 to 3 minutes.

[0053] Step 1.3, Pouring and Shaping: Pour the concrete mixture into the set template and smooth the surface.

[0054] Step 1.4, Curing: The large-pore concrete skeleton cast in Step 1.3 is cured for 3 to 7 days to achieve more than 30% of the design strength. During this process, the formwork is not removed and the process proceeds to the next step.

[0055] Step 2, Preparation of polymer-modified cement-based porous grouting material:

[0056] Step 2.1, weigh the following components: cement, rubber powder, polyurethane powder, aluminum powder, foaming agent, tackifier, water-reducing agent, and water;

[0057] Specifically, in step 2.1, the components, by mass percentage, are: cement 45%–50%, rubber powder 10%–20%, polyurethane fragments 8%–12%, aluminum powder 6%–10%, foaming agent 3.5%–5%, tackifier 1%–1.5%, water-reducing agent 1%–1.5%, and water 10%–15%; the sum of the mass percentages of all components is 100%. The cement is P·O32.5 ordinary Portland cement, P·O42.5 ordinary Portland cement, or CA60-II sulfoaluminate cement; the rubber powder is 40-60 mesh rubber powder; the polyurethane fragments have a particle size not exceeding 5mm; the aluminum powder is atomized spherical aluminum powder or high-spherical micro-fine aluminum powder; the foaming agent is sodium dodecyl sulfate, sodium rosinate, or sodium α-alkenyl sulfonate; the tackifier is a warm-rolled rubber cement tackifier, cellulose ether tackifier, or polyethylene oxide; and the water-reducing agent is a polycarboxylate high-efficiency water-reducing agent.

[0058] Step 2.2, Mixing: Mix cement, rubber powder and aluminum powder evenly, dissolve water-reducing agent in water, then dry mix polyurethane fragments with cement-rubber powder-aluminum powder mixture, then add 50% water-water-reducing agent mixture and stir, then add the remaining water-water-reducing agent mixture and stir, finally add foaming agent and thickener and stir at high speed to form a uniform and stable concrete mixture.

[0059] Specifically, in step 2.2, the dry mixing time of polyurethane granules and cement-rubber powder-aluminum powder mixture is 2-3 min; the mixing time of adding 50% water-water-reducing agent mixture is 1.5-2.5 min; the mixing time of adding the remaining water-water-reducing agent mixture is 2-3 min; the foaming agent and tackifier are added and high-speed mixing is 1.5-3 min; the high-speed mixing speed is greater than 1000 rad / min.

[0060] Step 3, prepare skeleton-grouted porous noise-reducing concrete:

[0061] Step 3.1, Grouting: The concrete mixture obtained in Step 2 is injected into the large-pore concrete skeleton structure obtained in Step 1 through a high-pressure grouting device. The grouting volume is controlled by the design porosity and the actual grouting pressure to ensure that the internal interconnected pores are completely filled by the grouting material.

[0062] Specifically, in step 3.1, grouting is stopped when the grouting volume of the high-pressure grouting equipment reaches 30% to 35% of the volume of the large-pore concrete skeleton and the grouting pressure reaches 2.5 MPa or higher.

[0063] Step 3.2, Curing: Smooth the surface of the grouting skeleton structure after grouting, remove the formwork and clean up the excess grout around it, and then cover it with plastic wrap for curing. The curing period is 28 days to obtain the skeleton grouting type porous noise reduction concrete pavement material.

[0064] The following are specific embodiments of the present invention. It should be noted that the present invention is not limited to the following specific embodiments. All equivalent modifications made based on the technical solutions of this application fall within the protection scope of the present invention.

[0065] Example 1:

[0066] This embodiment provides a skeleton-grouted porous noise-reducing concrete pavement material and its preparation method, including the following steps:

[0067] Step 1, Preparation of large-pore skeleton concrete: Take 10% P·O42.5 ordinary Portland cement, 8% S95 grade mineral powder, 72% crushed stone coarse aggregate with a particle size of 16-20mm, 1% polycarboxylate high-efficiency water-reducing agent, and 9% tap water by mass percentage, and set aside.

[0068] First, mix cement and mineral powder evenly, and dissolve the water-reducing agent in water and mix evenly. Then, dry mix the crushed stone coarse aggregate with the cement-mineral powder mixture for 1.0 min, add 50% of the water-water-reducing agent mixture and mix for 2.5 min, and finally add the remaining water-water-reducing agent mixture and continue mixing for 2.5 min to form a uniform and stable concrete mixture. Pour the resulting concrete mixture into concrete molds in three layers, tamping each layer 25 times with a tamping rod, smoothing the surface, and then curing the specimens for 7 days for later use.

[0069] Step 2, Preparation of polymer-modified cement-based porous grouting material: Weigh out 50% of P·O32.5 ordinary silicate cement, 10% of 40-mesh rubber powder, 10% of 5mm waste PU polyurethane fragments, 10% of atomized spherical aluminum powder, 5% of sodium rosinate cement foaming agent, 1.5% of warm wheel rubber cement tackifier, 1.5% of polycarboxylate high-efficiency water-reducing agent, and 12% of tap water by mass percentage, and set aside.

[0070] First, mix cement, rubber powder, and aluminum powder evenly, and dissolve the water-reducing agent in water. Then, dry mix the polyurethane fragments with the cement-rubber powder-aluminum powder mixture for 3 minutes. Next, add 50% of the water-water-reducing agent mixture and stir for 1.5 minutes. Then, add the remaining water-water-reducing agent mixture and stir for 2.5 minutes. Finally, add the foaming agent and thickener and stir at high speed for 1.5 minutes to form a uniform and stable concrete mixture for later use.

[0071] Step 3, Preparation of grouted porous noise-reducing concrete: The grout mixture obtained above is injected into the large-pore concrete skeleton structure using high-pressure grouting equipment. Grouting is stopped when the grout volume reaches 35% of the specimen volume and the grouting pressure reaches 2.5 MPa or higher. The surface of the grouted skeleton structure is smoothed, the formwork is removed, and excess grout is cleaned from the surrounding area. Then, it is covered with plastic wrap for curing. The curing period is 28 days to obtain the grouted porous noise-reducing concrete pavement material.

[0072] Example 2:

[0073] This embodiment provides a skeleton-grouted porous noise-reducing concrete pavement material and its preparation method, including the following steps:

[0074] Step 1, Preparation of large-pore skeleton concrete: Take 18% P·O 52.5 ordinary Portland cement, 5% S105 grade mineral powder, 68% basalt crushed stone with a particle size of 20-25mm, 1.5% polycarboxylate superplasticizer, and 7.5% tap water by mass percentage, and set aside.

[0075] First, mix cement and mineral powder evenly, and dissolve the water-reducing agent in water and mix evenly. Then, dry mix the crushed stone coarse aggregate with the cement-mineral powder mixture for 2 minutes. Next, add 50% of the water-water-reducing agent mixture and mix for 2 minutes. Finally, add the remaining water-water-reducing agent mixture and continue mixing for 2 minutes to form a uniform and stable concrete mixture. Pour the resulting concrete mixture into a concrete mold in three layers, tamping each layer 25 times with a tamping rod. Smooth the surface and then cure the specimens for 3 days for later use.

[0076] Step 2, Preparation of polymer-modified cement-based porous grouting material: Weigh out the following by mass percentage: 45% P·O42.5 ordinary silicate cement, 20% 60-mesh rubber powder, 12% polyurethane (PU) foam board fragments with a particle size of less than 5mm, 6% high-spherical fine aluminum powder, 4.5% sodium dodecyl sulfate cement foaming agent, 1% hydroxypropyl methylcellulose ether tackifier, 1.5% polycarboxylate superplasticizer, and 10% water. Set aside.

[0077] First, mix cement, rubber powder, and aluminum powder evenly, and dissolve the water-reducing agent in water. Then, dry mix the polyurethane fragments with the cement-rubber powder-aluminum powder mixture for 2.5 minutes. Next, add 50% of the water-water-reducing agent mixture and stir for 2 minutes. Then, add the remaining water-water-reducing agent mixture and stir for 2 minutes. Finally, add the foaming agent and thickener and stir at high speed for 1.5 minutes to form a uniform and stable concrete mixture for later use.

[0078] Step 3, Preparation of grouted porous noise-reducing concrete: The grout mixture obtained above is injected into the large-pore concrete skeleton structure using high-pressure grouting equipment. Grouting is stopped when the grout volume reaches 35% of the specimen volume and the grouting pressure reaches 2.5 MPa or higher. The surface of the grouted skeleton structure is smoothed, the formwork is removed, and excess grout is cleaned from the surrounding area. Then, it is covered with plastic wrap for curing. The curing period is 28 days to obtain the grouted porous noise-reducing concrete pavement material.

[0079] Example 3:

[0080] This embodiment provides a skeleton-grouted porous noise-reducing concrete pavement material and its preparation method, including the following steps:

[0081] Step 1, Preparation of large-pore skeleton concrete: Take 14% P·O52.5 ordinary Portland cement, 10% S95 grade mineral powder, 65% granite crushed stone with a particle size of 19-26mm, 1% polycarboxylate superplasticizer, and 10% tap water by mass percentage, and set aside.

[0082] First, mix cement and mineral powder evenly, and dissolve the water-reducing agent in water and mix evenly. Then, dry mix the crushed stone coarse aggregate with the cement-mineral powder mixture for 1.5 minutes. Next, add 50% of the water-water-reducing agent mixture and mix for 1.5 minutes. Finally, add the remaining water-water-reducing agent mixture and continue mixing for 2.5 minutes to form a uniform and stable concrete mixture. Pour the resulting concrete mixture into concrete molds in three layers, tamping each layer 25 times with a tamping rod. Smooth the surface and then cure the specimens for 3 days for later use.

[0083] Step 2, Preparation of polymer-modified cement-based porous grouting material: Weigh out the following by mass percentage: 48% CA60-II sulfoaluminate cement, 15% 60-mesh rubber powder, 8% waste PU polyurethane fragments, 8% high-spherical fine aluminum powder, 3.5% sodium α-alkenyl sulfonate cement foaming agent, 1.5% polyethylene oxide cement tackifier, 1% polycarboxylate high-efficiency water-reducing agent, and 15% tap water, and set aside.

[0084] First, mix cement, rubber powder, and aluminum powder evenly, and dissolve the water-reducing agent in water. Then, dry mix the polyurethane fragments with the cement-rubber powder-aluminum powder mixture for 2.5 minutes. Next, add 50% of the water-water-reducing agent mixture and stir for 2 minutes. Then, add the remaining water-water-reducing agent mixture and stir for 2 minutes. Finally, add the foaming agent and thickener and stir at high speed for 2 minutes to form a uniform and stable concrete mixture for later use.

[0085] Step 3, Preparation of grouted porous noise-reducing concrete: The grout mixture obtained above is injected into the large-pore concrete skeleton structure using high-pressure grouting equipment. Grouting is stopped when the grout volume reaches 30% of the specimen volume and the grouting pressure reaches 2.5 MPa or higher. The surface of the grouted skeleton structure is smoothed, the formwork is removed, and excess grout is cleaned from the surrounding area. Then, it is covered with plastic wrap for curing. The curing period is 28 days to obtain the grouted porous noise-reducing concrete pavement material.

[0086] The sound absorption effect of porous materials can be represented by their sound absorption coefficient. The sound absorption coefficient is the ratio of the sound energy absorbed by the material surface to the incident sound energy. The vertical sound absorption coefficient (hereinafter referred to as the sound absorption coefficient) is commonly measured using the standing wave tube method. This experiment follows the relevant provisions of the national standard "Standing Wave Tube Method for Measurement of Sound Absorption Coefficient and Acoustic Impedance" GBJ88-85, using a standing wave tube + frequency analyzer + audio signal generator. The audio signal generator drives the loudspeaker to radiate plane sound waves inside the standing wave tube. After encountering the test sample, the emitted wave is superimposed with the incident wave to form a standing wave. The sound pressure (P) of the standing wave antinode is measured using a movable microphone probe. max ) and node sound pressure (P min The sound absorption coefficient of the sample can be measured using an amplifier and filter with a specially calibrated scale, along with their corresponding positions within the standing wave tube. Figure 3 The sound absorption coefficient test results show that the sound absorption coefficient of the skeleton-grouted porous noise-reducing concrete of the present invention is 2.7 times that of ordinary porous concrete and 20 times that of ordinary concrete in the frequency range of 600Hz to 1200Hz. The skeleton-grouted porous concrete material of the present invention has significant advantages in sound absorption and noise reduction.

Claims

1. A method for preparing a skeleton-grouted porous noise-reducing concrete pavement material, characterized in that, Includes the following steps: Step 1, Preparation of large-pore skeleton concrete: Step 1.1: Weigh the following components: cement, mineral powder, crushed stone coarse aggregate, water-reducing agent, and water; Step 1.2, Mixing: First, mix the cement and mineral powder evenly, and dissolve the water-reducing agent in water and mix evenly. Then, dry mix the crushed stone coarse aggregate with the cement-mineral powder mixture, add 50% of the water-water-reducing agent mixture and stir. Finally, add the remaining water-water-reducing agent mixture and continue stirring to form a uniform and stable concrete mixture. Step 1.3, Pouring and Shaping: Pour the concrete mixture into the set template and smooth the surface. Step 1.4, Curing: The large-pore concrete skeleton poured and formed in Step 1.3 should be cured for 3-7 days; the formwork is not removed and the process proceeds to the next step. Step 2, Preparation of polymer-modified cement-based porous grouting material: Step 2.1, weigh the following components: cement, rubber powder, polyurethane powder, aluminum powder, foaming agent, tackifier, water-reducing agent, and water; Step 2.2, Mixing: Mix cement, rubber powder and aluminum powder evenly, dissolve water-reducing agent in water, then dry mix polyurethane fragments with cement-rubber powder-aluminum powder mixture, then add 50% water-water-reducing agent mixture and stir, then add the remaining water-water-reducing agent mixture and stir, finally add foaming agent and thickener and stir at high speed to form a uniform and stable concrete mixture. Step 3, prepare skeleton-grouted porous noise-reducing concrete: Step 3.1, Grouting: The concrete mixture obtained in Step 2 is injected into the large-pore concrete skeleton structure obtained in Step 1 through a high-pressure grouting device. The grouting volume is controlled by the design porosity and the actual grouting pressure to ensure that the internal interconnected pores are completely filled by the grouting material. Step 3.2, Curing: Smooth the surface of the grouting skeleton structure after grouting, remove the formwork and clean up the excess grout around it, and then cover it with plastic wrap for curing. The curing period is 28 days to obtain the skeleton grouting type porous noise reduction concrete pavement material. In step 1.1, the components, by mass percentage, are: cement 10%~18%, mineral powder 5%~10%, crushed stone coarse aggregate 65%~72%, water-reducing agent 1%~1.5%, and water 7.5~10%; the sum of the mass percentages of all components is 100%. In step 1.1, the cement is P·O 42.5 ordinary Portland cement or P·O 52.5 ordinary Portland cement; The ore powder is S95 grade granulated blast furnace slag powder or S105 grade granulated blast furnace slag powder; The coarse aggregate of the crushed stone is basalt crushed stone or granite crushed stone with a particle size of 16~26mm; The water-reducing agent is a polycarboxylate superplasticizer; In step 1.2, the dry mixing time of the crushed stone coarse aggregate and the cement-mineral powder mixture is 1~2 min; the mixing time of adding 50% of the water-water-reducing agent mixture is 1.5~3 min; the mixing time of adding the remaining water-water-reducing agent mixture is 2~3 min. In step 2.1, the components, by mass percentage, are: cement 45%~50%, rubber powder 10%~20%, polyurethane fragments 8%~12%, aluminum powder 6%~10%, foaming agent 3.5%~5%, tackifier 1%~1.5%, water-reducing agent 1%~1.5%, and water 10%~15%; the sum of the mass percentages of all components is 100%. In step 2.1, the cement is P·O32.5 ordinary Portland cement, P·O42.5 ordinary Portland cement, or CA60-II sulfoaluminate cement. The rubber powder is 40-60 mesh. The particle size of polyurethane fragments should not exceed 5mm; The aluminum powder is either atomized spherical aluminum powder or high-spherical micro-fine aluminum powder; The foaming agent is sodium dodecyl sulfate, sodium rosinate, or α-ammonium alpha-sulfate; The tackifier is a warm-rolled cement tackifier, a cellulose ether tackifier, or polyethylene oxide; The water-reducing agent is a polycarboxylate superplasticizer; In step 2.2, the dry mixing time of polyurethane fragments and cement-rubber powder-aluminum powder mixture is 2-3 minutes; the mixing time of adding 50% water-water-reducing agent mixture is 1.5-2.5 minutes; the mixing time of adding the remaining water-water-reducing agent mixture is 2-3 minutes; the mixing time of adding foaming agent and tackifier and high-speed mixing is 1.5-3 minutes. In step 3.1, grouting is stopped when the grouting volume of the high-pressure grouting equipment reaches 30% to 35% of the volume of the large-pore concrete skeleton and the grouting pressure reaches 2.5 MPa or higher.

2. The preparation method of the skeleton-grouted porous noise-reducing concrete pavement material as described in claim 1, characterized in that, The high-speed stirring speed is greater than 1000 rad / min.

3. A skeleton-grouted porous noise-reducing concrete pavement material, characterized in that, The concrete pavement material is prepared by the method for preparing the skeleton grouting type porous noise-reducing concrete pavement material as described in claim 2.

Images