Method for determining the amount of rubber particles for full-frequency noise reduction pavement mixtures

Abstract

The application discloses a method for determining the amount of rubber particles in a full-frequency noise reduction pavement mixture; 1, selecting an amount of rubber particles; 2, preparing a full-frequency noise reduction pavement mixture test piece; 3, testing the actual stiffness and actual void ratio of the full-frequency noise reduction pavement mixture test piece; and determining whether the desired noise reduction requirement is met; 4, testing the wear resistance of the full-frequency noise reduction pavement mixture test piece; and determining whether the wear resistance of the full-frequency noise reduction pavement meets the requirement; 5, testing the interface strength of the full-frequency noise reduction pavement mixture test piece; and determining whether the interface coordination of the full-frequency noise reduction pavement meets the requirement; 6, the amount of rubber particles in the full-frequency noise reduction pavement mixture test piece in steps 3 to 5 is the appropriate amount of rubber particles. The application takes the amount of rubber particles as the core, takes noise reduction requirement, wear resistance and interface strength as indexes, and can ensure excellent noise reduction capacity and road performance of the full-frequency noise reduction pavement.

Description

Technical Field

[0001] This invention relates to the field of road construction technology, and in particular to a method for determining the amount of rubber particles used in full-frequency noise-reducing road mixtures. Background Technology

[0002] In existing technologies, porous asphalt pavement is often used to reduce the interference of tire / road noise (the main source of traffic noise) on the work and life of residents along the route.

[0003] Extensive practical experience has shown that porous asphalt pavement can reduce traffic noise by 3 to 6 dB compared to conventional dense asphalt pavement, mainly in terms of reducing high-frequency noise above 1000 Hz. However, at the same time, this type of pavement will exacerbate the harm of low-frequency noise below 1000 Hz to drivers and passengers in vehicles.

[0004] In other words, while this porous asphalt pavement protects residents along the road, it also harms the interior environment of vehicles for drivers and passengers. Therefore, in order to protect both residents along the road and drivers and passengers, there is an urgent need to adopt full-frequency noise-reducing pavement.

[0005] To reduce low-frequency tire / road noise, current technical measures primarily focus on reducing road surface stiffness, thereby decreasing tire vibration. This is typically achieved by incorporating rubber granules obtained from crushed waste tires into the road mixture (partially or completely replacing aggregate) to lower road surface stiffness. Rubber granules are the core of full-frequency noise-reducing pavements; currently, the minimum rubber granule content in full-frequency noise-reducing pavements is only about 10 wt%, while the maximum reaches about 90 wt%. This significant variation in rubber granule content presents considerable challenges to the design of full-frequency noise-reducing pavements.

[0006] The design of rubber granules is the soul of full-frequency noise reduction pavement design, because rubber granules not only directly affect the low-frequency noise reduction capability of the pavement, but also its service durability (wear resistance and interface compatibility). Determining the amount of rubber granules is one of the core issues in the current design of full-frequency noise reduction pavements.

[0007] Therefore, how to accurately determine the amount of rubber particles in full-frequency noise-reducing pavement and provide a reference for the composition design of full-frequency noise-reducing pavement mixtures has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0008] In view of the above-mentioned deficiencies of the prior art, the present invention provides a method for determining the amount of rubber particles in full-frequency noise-reducing pavement mixtures. The purpose is to accurately determine the amount of rubber particles in full-frequency noise-reducing pavement mixtures, and to provide a reference for the composition design of full-frequency noise-reducing pavement mixtures.

[0009] To achieve the above objectives, this invention discloses a method for determining the amount of rubber particles used in full-frequency noise-reducing pavement mixtures, comprising the following steps:

[0010] Step 1: Select the amount of rubber granules to be used based on the technical specifications of the full-frequency noise reduction pavement to be constructed;

[0011] Step 2: Prepare full-frequency noise-reducing pavement mixture specimens. Determine the amount of polyurethane, aggregate, and manufacturing porosity of the full-frequency noise-reducing pavement mixture specimens based on the amount of rubber particles used.

[0012] Step 3: Test the actual stiffness and actual porosity of the full-frequency noise reduction pavement mixture specimen; and determine whether the expected noise reduction requirements are met based on the actual stiffness and actual porosity; if yes, continue with the subsequent steps; if no, optimize the amount of rubber particles and re-execute all steps starting from step 2.

[0013] Step 4: Test the abrasion resistance of the full-frequency noise reduction pavement mixture specimen; and determine whether the abrasion resistance meets the requirements of the full-frequency noise reduction pavement based on the abrasion resistance; if yes, continue with the subsequent steps; if no, optimize the amount of rubber particles and re-execute all steps starting from step 2.

[0014] Step 5: Test the interfacial strength of the full-frequency noise-reducing pavement mixture specimen; and determine whether the interfacial compatibility of the full-frequency noise-reducing pavement is met based on the interfacial strength; if yes, continue with the subsequent steps; if no, optimize the amount of rubber particles and re-execute all steps starting from step 2.

[0015] Step 6: The amount of rubber particles used in the full-frequency noise reduction pavement mixture specimen obtained through steps 3 to 5 is the appropriate amount of rubber particles.

[0016] Preferably, the amount of rubber granules is 10 wt% to 80 wt%, the amount of aggregate is 85 wt% to 5 wt%, and the amount of polyurethane is 5 wt% to 15 wt%.

[0017] Preferably, for every 0.5 dB increase in the noise reduction requirement of the full-frequency noise reduction pavement, the content of the added rubber particles increases by 3 wt% to 6 wt%, the corresponding amount of polyurethane increases by 0.4 wt% to 0.6 wt%, and the corresponding amount of aggregate decreases by 3.4 wt% to 6.6 wt%.

[0018] Preferably, the mixture of the full-frequency noise-reducing pavement has a skeleton void structure with a void ratio of 18% to 40%.

[0019] Preferably, the actual stiffness is determined by a uniaxial compression dynamic modulus test;

[0020] The actual porosity is determined using a density test, i.e., the volumetric method.

[0021] Preferably, in step 3, noise spectrum characterization is used to comprehensively determine whether the specimen meets the expected noise reduction requirements based on the actual stiffness and the actual porosity.

[0022] Preferably, the wear resistance is determined by a road / tire wear test, and the wear quality of the specimen is used to characterize it.

[0023] Preferably, the interface strength is determined by a direct shear or oblique shear test, and the test specimen also includes an asphalt or cement pavement mixture placed on the bottom surface of the full-frequency noise-reducing pavement mixture specimen as a lower layer.

[0024] The beneficial effects of this invention are:

[0025] This invention focuses on the amount of rubber particles used, and uses noise reduction requirements, wear resistance, and interfacial strength as indicators to design a full-frequency noise-reducing pavement mixture. This ensures the excellent noise reduction capability and road performance of the full-frequency noise-reducing pavement, significantly reducing loosening and delamination problems, and changing the problem of arbitrary rubber particle usage in existing full-frequency noise-reducing pavements.

[0026] This invention takes the amount of rubber particles as a starting point to determine the amount of polyurethane and aggregates, thus changing the problem of arbitrary combination of the three in existing designs, making the design of full-frequency noise reduction pavement mixtures more reasonable and effective.

[0027] The following will further explain the concept, specific structure, and technical effects of the present invention in conjunction with the accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention. Attached Figure Description

[0028] Figure 1 A flowchart of an embodiment of the present invention is shown.

[0029] Figure 2 The diagram shows a noise spectrum comparison between an embodiment of the present invention and a control example. Detailed Implementation

[0030] Example 1

[0031] like Figure 1 As shown, the method for determining the amount of rubber granules used in full-frequency noise-reducing pavement mixtures includes the following steps:

[0032] Step 1: Select the amount of rubber granules to be used based on the technical specifications of the full-frequency noise reduction pavement to be constructed;

[0033] Step 2: Prepare full-frequency noise reduction pavement mixture specimens. Determine the amount of polyurethane, aggregate, and manufacturing porosity of the full-frequency noise reduction pavement mixture specimens based on the amount of rubber particles used.

[0034] Step 3: Test the actual stiffness and actual porosity of the full-frequency noise reduction pavement mixture specimen; and determine whether the expected noise reduction requirements are met based on the actual stiffness and actual porosity; if yes, continue with the subsequent steps; if no, optimize the amount of rubber granules and re-execute all steps starting from Step 2.

[0035] Step 4: Test the abrasion resistance of the full-frequency noise reduction pavement mixture specimen; and determine whether the abrasion resistance meets the requirements of the full-frequency noise reduction pavement based on the abrasion resistance; if yes, continue to the next step; if no, optimize the amount of rubber particles and repeat all steps from step 2.

[0036] Step 5: Test the interfacial strength of the full-frequency noise reduction pavement mixture specimen; and determine whether the interfacial compatibility of the full-frequency noise reduction pavement is met based on the interfacial strength; if yes, continue with the subsequent steps; if no, optimize the amount of rubber granules and re-execute all steps starting from step 2.

[0037] Step 6: The appropriate amount of rubber particles is determined by the amount of rubber particles used in the full-frequency noise reduction pavement mixture specimens obtained from Steps 3 to 5.

[0038] This invention uses noise reduction requirements as the primary testing standard, laying the foundation for full-frequency noise reduction (especially low-frequency noise reduction); and uses wear resistance and interface compatibility as the second and third testing standards, focusing on the loosening and delamination problems of full-frequency noise-reduced pavements during operation. Full-frequency noise-reduced pavements that meet noise reduction requirements and satisfy wear resistance and interface compatibility will possess long-term durable full-frequency noise reduction capabilities, providing an effective way to alleviate the acoustic environment problems along roads and inside vehicles.

[0039] In some embodiments, the amount of rubber granules is 10 wt% to 80 wt%, the amount of aggregate is 85 wt% to 5 wt%, and the amount of polyurethane is 5 wt% to 15 wt%.

[0040] In some embodiments, for every 0.5 dB increase in the noise reduction requirement of the full-frequency noise reduction pavement, the content of the added rubber particles increases by 3 wt% to 6 wt%, the corresponding amount of polyurethane increases by 0.4 wt% to 0.6 wt%, and the corresponding amount of aggregate decreases by 3.4 wt% to 6.6 wt%.

[0041] In some embodiments, the mixture of the full-frequency noise-reducing pavement has a skeleton-void structure with a porosity of 18% to 40%.

[0042] In some embodiments, the actual stiffness is determined using a uniaxial compression dynamic modulus test;

[0043] The actual porosity is determined using a density test, i.e., the volumetric method.

[0044] In some embodiments, in step 3, noise spectrum characterization is used to determine whether the specimen meets the expected noise reduction requirements based on the actual stiffness and actual porosity.

[0045] In some embodiments, the abrasion resistance is determined by road / tire abrasion tests, characterized by the abrasion mass of the specimen.

[0046] In some embodiments, the interfacial strength is determined by a direct shear or oblique shear test, and the test specimen also includes an asphalt or cement pavement mixture placed on the bottom surface of the full-frequency noise-reducing pavement mixture specimen as a lower layer.

[0047] Example 2

[0048] The method for determining the amount of rubber particles in the full-frequency noise-reducing pavement mixture of the present invention is based on the appendix. Figure 1 The selected / determined full-frequency noise-reducing pavement mixture consists of the following components by weight:

[0049] 39 parts of rubber granules

[0050] 12 parts of polyurethane

[0051] 49 portions of material were collected.

[0052] The full-frequency noise-reducing pavement mixture has a skeleton-void structure; the aggregate consists of coarse aggregate, fine aggregate and filler, with a weight ratio of 82:14:4; the porosity is 31.9%.

[0053] The stiffness and porosity of the specimens were determined by uniaxial compression dynamic modulus test and density test (volume method), respectively, and the test temperature was maintained at 25℃.

[0054] The noise reduction capability is determined by a combination of the stiffness and porosity of the specimen, and is characterized by the noise spectrum.

[0055] The abrasion resistance was determined by a road / tire abrasion test at a temperature of 25°C, and the abrasion quality of the specimen was used to characterize it.

[0056] The interfacial strength was determined by direct shear or oblique shear test at a test temperature of 25°C. The test specimen consisted of a full-frequency noise-reducing pavement (upper layer) and an asphalt or cement pavement (lower layer).

[0057] Comparison Example

[0058] The difference between the comparative example and the embodiment is that, according to the appendix Figure 1 The selected / determined full-frequency noise-reducing pavement mixture consists of the following components by weight:

[0059] 19 parts of rubber granules,

[0060] 10 parts of polyurethane

[0061] 71 portions of material were collected.

[0062] The weight ratio of coarse aggregate, fine aggregate, and filler is 75:17:8; the porosity is 27.5%.

[0063] Comparison effect

[0064] Based on the material composition ratios of the embodiments, full-frequency noise-reducing pavement mixture specimens were prepared, and stiffness and porosity tests were conducted to verify their noise reduction capabilities. The abrasion resistance and interfacial strength of the specimens were also tested to verify the abrasion resistance and interfacial compatibility of the full-frequency noise-reducing pavement. Similarly, based on the material composition ratios of the control examples, specimens were prepared and corresponding tests were performed.

[0065] A comparison of the noise reduction performance (noise reduction spectrum) of the examples and control examples is attached. Figure 2 As shown in the figure; other performance comparisons of the embodiments and comparative examples are shown in Table 1.

[0066] Table 1

[0067] project Example 2 Comparison Example Design Requirements Specimen stiffness / MPa 64 214 <500 Porosity of the specimen / % 31.9 27.5 18 to 40 Specimen noise reduction capability / dB 11.5 7.6 >10 Specimen wear mass / g 2090 3604 <4000 Specimen interfacial strength / MPa 1.0 1.2 >0.8

[0068] As can be seen from Table 1, the noise reduction capability of this embodiment (meeting the noise reduction requirement of 10dB) is much higher than that of the control example, the wear mass of the specimen is much lower than that of the control example, and the interface strength of the specimen is slightly lower than that of the control example, indicating that the rubber particle dosage of 39wt% determined in this embodiment 2 is more appropriate.

[0069] Depend on Figure 2 It can be seen that, due to the lower stiffness (due to the higher rubber particle content) and higher porosity of the noise-reducing pavement mixture in Example 2, the noise reduction capability of Example 2 is significantly better than that of the control group across the entire frequency range (200Hz–5000Hz). The increased rubber particle content (39wt% vs. 19wt%) helps reduce low-frequency noise below 800Hz; the increased porosity (31.9% vs. 27.0%) helps reduce high-frequency noise above 1000Hz. This further demonstrates that the 39wt% rubber particle content in the full-frequency noise-reducing pavement mixture of Example 2 is reasonable. It also shows that the method for determining the amount of rubber particles in the full-frequency noise-reducing pavement mixture of this invention is feasible.

[0070] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A method for determining the amount of rubber granules used in full-frequency noise-reducing pavement mixtures; characterized in that, Includes the following steps: Step 1: Select the amount of rubber granules to be used based on the technical specifications of the full-frequency noise reduction pavement to be constructed; The amount of rubber granules is 10wt% to 80wt%, the amount of aggregate is 85wt% to 5wt%, and the amount of polyurethane is 5wt% to 15wt%. The technical specifications are noise reduction, wear resistance, and interface strength. Step 2: Prepare full-frequency noise reduction pavement mixture specimens. Determine the amount of polyurethane, aggregate, and manufacturing porosity of the full-frequency noise reduction pavement mixture specimens based on the amount of rubber particles used. For every 0.5 dB increase in noise reduction requirements for full-frequency noise-reducing pavements, the content of added rubber particles increases by 3 wt% to 6 wt%, the corresponding amount of polyurethane increases by 0.4 wt% to 0.6 wt%, and the corresponding amount of aggregate decreases by 3.4 wt% to 6.6 wt%. The mixture used in the full-frequency noise reduction pavement has a skeleton-void structure with a porosity of 18% to 40%. Step 3: Test the actual stiffness and actual porosity of the full-frequency noise reduction pavement mixture specimen; and determine whether the expected noise reduction requirements are met based on the actual stiffness and actual porosity; if yes, continue with the subsequent steps; if no, optimize the amount of rubber particles and re-execute all steps starting from step 2. Step 4: Test the abrasion resistance of the full-frequency noise reduction pavement mixture specimen; and determine whether the abrasion resistance meets the requirements of the full-frequency noise reduction pavement based on the abrasion resistance; if yes, continue with the subsequent steps; if no, optimize the amount of rubber particles and re-execute all steps starting from step 2. Step 5: Test the interfacial strength of the full-frequency noise-reducing pavement mixture specimen; and determine whether the interfacial compatibility of the full-frequency noise-reducing pavement is met based on the interfacial strength; if yes, continue with the subsequent steps; if no, optimize the amount of rubber particles and re-execute all steps starting from step 2. Step 6: The amount of rubber particles used in the full-frequency noise reduction pavement mixture specimen obtained through steps 3 to 5 is the appropriate amount of rubber particles.

2. The method for determining the amount of rubber particles in full-frequency noise-reducing pavement mixture according to claim 1, characterized in that, The actual stiffness was determined by a uniaxial compression dynamic modulus test. The actual porosity is determined using a density test, i.e., the volumetric method.

3. The method for determining the amount of rubber particles in full-frequency noise-reducing pavement mixture according to claim 1, characterized in that, In step 3, noise spectrum characterization is used to comprehensively determine whether the specimen meets the expected noise reduction requirements based on the actual stiffness and the actual porosity.

4. The method for determining the amount of rubber particles in full-frequency noise-reducing pavement mixture according to claim 1, characterized in that, The wear resistance is determined by road / tire wear tests and characterized by the wear quality of the specimen.

5. The method for determining the amount of rubber particles in full-frequency noise-reducing pavement mixture according to claim 1, characterized in that, The interface strength is determined by a direct shear or oblique shear test, and the test specimen also includes an asphalt or cement pavement mixture placed on the bottom surface of the full-frequency noise reduction pavement mixture specimen as a lower layer.

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