Anti-skid pavement performance regulation and control method based on waste refractory material and recycled aggregate

Abstract

The invention relates to the technical field of road engineering materials, and discloses an anti-skid pavement performance regulation and control method based on a waste refractory material and recycled aggregate, the regulation and control method comprises the following steps: preparing a pavement sample according to the recycled aggregate, and carrying out abrasion by adopting an accelerated loading abrasion tester, data of a dynamic friction coefficient, an average section depth, a macroscopic texture parameter and a microscopic texture parameter are obtained, correlation analysis among different parameters is carried out, and parameters without correlation are selected as aggregate characteristic parameters; performing a dynamic modulus test on the mixture sample at different temperatures and load frequencies, and establishing a dynamic modulus prediction model; and judging whether the pavement performance requirements are met or not based on the aggregate characteristic parameters and the dynamic modulus prediction model, if not, adjusting the grading and performance parameters of the recycled aggregate, and repeating the steps until the pavement performance requirements are met. According to the regulation and control method disclosed by the invention, through testing and modeling, the performance and grading of the recycled aggregate are continuously optimized so as to ensure that the antiskid pavement based on the waste refractory material meets the performance requirements.

Description

Technical Field

[0001] This invention relates to the field of road engineering materials technology, and in particular to a method for controlling the anti-skid pavement performance based on waste refractory materials and recycled aggregates. Background Technology

[0002] Refractory materials are crucial for high-temperature industries and are also resource-intensive. Due to the large volume of refractory materials used, especially high-alumina refractories, most of the waste refractory materials have long been landfilled or used as downgraded refractory raw materials, resulting in low added value. More than ten million tons of waste refractory materials are generated annually, but less than 10% are utilized at low value, and the large-scale accumulation or landfilling leads to soil and water pollution.

[0003] Road surface friction is a key factor in improving road safety. Higher friction can be achieved through the use of special HFST (High Friction Surface Treatment). Current HFST is mainly prepared using binders and natural wear-resistant aggregates such as basalt, limestone, and granite, or high-friction calcined bauxite aggregates. HFST is suitable for road surfaces in special sections of highways (such as tunnel entrances and exits, curves, long longitudinal slopes, and other accident-prone sections). High-friction-resistant calcined bauxite plays a crucial role in the skid resistance of HFST. Calcined bauxite is produced by sintering bauxite in kilns at temperatures above 1500°C. Calcined bauxite aggregate is expensive, while natural raw materials are resource-intensive and costly to mine. To meet the demand for solid waste utilization, it is necessary to find a low-cost, low-energy-consumption, and environmentally friendly high-friction alternative aggregate from solid waste. Given the excellent properties of waste refractory materials, they have the potential to be a high-friction alternative aggregate for HFST.

[0004] Currently, there are many types and large quantities of waste refractory materials. Recycled aggregates made from waste refractory materials cannot be effectively used. Furthermore, HFST has high requirements for the anti-skid performance of aggregates, and existing technologies cannot select recycled aggregates that meet the requirements of anti-skid pavement specifications. Summary of the Invention

[0005] The purpose of this invention is to overcome the problems of the large variety and quantity of existing waste refractory materials, the ineffective application of recycled aggregates prepared from waste refractory materials, and the high requirements of HFST for the anti-skid performance of aggregates. This invention provides a method for controlling the anti-skid pavement performance based on waste refractory materials and recycled aggregates.

[0006] In a first aspect, the present invention provides a method for regulating the anti-skid pavement performance based on waste refractory materials, wherein the anti-skid pavement includes a wearing layer composed of recycled aggregate, the recycled aggregate being prepared from waste refractory materials, and the regulation method includes the following steps: S1. Obtain the recycled aggregate; S2. Prepare road surface samples based on the recycled aggregate, and use an accelerated loading abrasion tester to abrade the road surface samples for different numbers of times under a set load to obtain dynamic friction coefficient, average cross-sectional depth, macro-texture parameters and micro-texture parameters; perform correlation analysis between different parameters based on dynamic friction coefficient, average cross-sectional depth, macro-texture parameters and micro-texture parameters, and select parameters with no correlation as aggregate characteristic parameters; Prepare a mixture sample of the recycled aggregate and binder, and conduct dynamic modulus tests on the mixture sample at different temperatures and loading frequencies. Use the dynamic modulus data to establish a dynamic modulus prediction model. S3. Based on the aggregate characteristic parameters and the dynamic modulus prediction model, determine whether the recycled aggregate meets the pavement performance requirements. If not, adjust the gradation and performance parameters of the recycled aggregate, and repeat steps S1 to S3 until the pavement performance requirements are met.

[0007] As a preferred embodiment of the present invention, the waste refractory material is a high-alumina refractory material.

[0008] As a preferred embodiment of the present invention, the waste refractory material includes at least one of silicon-mullite bricks, corundum-magnesium-alumina spinel castables, and high-voltage electrical porcelain. High-voltage electrical porcelain refers to waste products, substandard products, and waste materials generated during the production of high-voltage electrical porcelain due to imperfect processes or unqualified testing, as well as waste materials generated during use due to damage.

[0009] As a preferred embodiment of the present invention, the macroscopic texture parameters include the arithmetic mean deviation of the profile (Ra), the root mean square deviation of the profile (Rq), and the skewness (Rsk), and the microscopic texture parameters include surface roughness.

[0010] As a preferred embodiment of the present invention, in step S2, a friction coefficient decay prediction model is established for the dynamic friction coefficient data. The friction coefficient decay prediction model is as follows: μ(n) = A·exp(B·n) Where μ is the dynamic friction coefficient, A is the weighting coefficient, B is the rate of change, and n is the wear cycle.

[0011] As a preferred embodiment of the present invention, in the correlation analysis of dynamic friction coefficient, average cross-sectional depth, macro-texture parameters and micro-texture parameters in step S2, the correlation between different parameters is analyzed by calculating the Pearson correlation coefficient.

[0012] As a preferred embodiment of the present invention, in the correlation analysis, when the correlation coefficient R... 2 A correlation coefficient greater than 0.6 indicates that the two parameters are correlated. 2If the value is ≤0.6, it means that the two parameters are not correlated.

[0013] As a preferred embodiment of the present invention, the anti-skid pavement further includes a base layer, on which an adhesive layer and the wear layer are sequentially disposed.

[0014] As a preferred embodiment of the present invention, the road surface sample includes the base layer, the bonding layer and the wear layer arranged in sequence, wherein the base layer is a concrete structure.

[0015] As a preferred embodiment of the present invention, the adhesive layer is composed of the adhesive, which includes at least one of epoxy resin adhesive, rosin ester adhesive, polyurethane adhesive, acrylic resin adhesive and polyester resin adhesive.

[0016] As a preferred embodiment of the present invention, the mixture sample is a cylindrical structure with a diameter of 5-20 cm and a height of 10-25 cm.

[0017] In a second aspect, the present invention provides a recycled aggregate based on waste refractory materials, wherein the recycled aggregate is obtained by the aforementioned method for controlling the anti-skid pavement performance based on waste refractory materials.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention provides a method for controlling the anti-skid pavement performance based on waste refractory materials. The method involves preparing pavement samples using recycled aggregates, and using an accelerated abrasion tester to subject the samples to abrasion at different times under a set load. Dynamic friction coefficient data, average cross-sectional depth data, macro-texture parameter data, and micro-texture parameter data are measured and recorded. Correlation analysis is performed on these data to select parameters without correlation, which are then used as aggregate characteristic parameters for subsequent pavement performance assessment. Dynamic modulus tests are conducted on the mixed samples under different temperature and load frequencies. The dynamic modulus prediction model is established using the obtained dynamic modulus data, reflecting the mechanical properties of the mixture under different working conditions. Based on the aggregate characteristic parameters of the recycled aggregates and the dynamic modulus prediction model, it is determined whether the pavement meets performance requirements. If not, the gradation and performance parameters of the recycled aggregates need to be adjusted, and the entire process is repeated until the pavement performance meets the requirements. This invention's control method continuously optimizes the performance and gradation of recycled aggregates through experimentation and modeling to ensure that the anti-skid pavement based on waste refractory materials meets performance requirements.

[0019] 2. This invention provides a dynamic performance control method that solves the problem of long-term performance degradation of traditional anti-skid materials by coupling the morphological characteristics of recycled aggregates with the service environment, and obtains recycled aggregates that meet the requirements of anti-skid pavement. This method can not only realize the reuse of waste refractory materials, but also provide special properties for pavement. It is suitable for the whole life cycle performance optimization of anti-skid surface layer of high-grade highways. Attached Figure Description

[0020] Figure 1 Here is a photograph of the actual road surface sample. Figure 2 The dynamic friction coefficient decay curve (a) μ 40 (b) μ 60 ; Figure 3 MPD decay curves for different aggregates; Figure 4 For μ 40 Correlation analysis chart with wear cycle; Figure 5 Images showing the testing process of calcined bauxite; Figure 6 Images of the basalt testing process; Figure 7 Images of the steel slag testing process; Figure 8 Images showing the testing process for silica-mullite bricks; Figure 9 Images of the casting refractory testing process; Figure 10 Images showing the testing process of high-voltage electrical porcelain. Figure 11 Three-dimensional morphological images of different HFSTs before wear; Figure 12 Three-dimensional and planar images of different HFSTs after 140k wear cycles; Figure 13 To highlight the area ratio of aggregates; Figure 14 Trends of HFST texture characterization parameters prepared for different aggregates as a function of load; Figure 15 For MPD, μ 40 The correlation between Rq and Ra; Figure 16 SEM images of six types of aggregates; Figure 17 Images showing the surface roughness of calcined bauxite aggregate: (a) before wear; (b) after wear; Figure 18 Images showing the surface roughness of basalt aggregate: (a) before wear; (b) after wear; Figure 19Images showing the surface roughness of steel slag aggregate: (a) before wear; (b) after wear; Figure 20 Images showing the surface roughness of silica-mullite brick aggregates: (a) before wear; (b) after wear; Figure 21 Images showing the surface roughness of castable aggregates: (a) before wear; (b) after wear; Figure 22 Images showing the surface roughness of high-voltage electrical porcelain aggregate: (a) before wear; (b) after wear; Figure 23 Data on surface roughness of different aggregates; Figure 24 This is a dynamic modulus curve at a temperature of 21℃. Detailed Implementation

[0021] The present invention will now be described in further detail with reference to specific embodiments. However, this should not be construed as limiting the scope of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0022] Unless otherwise specified, the use of terms such as "upper," "lower," "left," "right," "center," "inner," and "outer" to indicate orientation or positional relationships in the description of specific embodiments of the present invention is based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is typically placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0023] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," "parallel," and "coaxial" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, parallel, or coaxial. Slight tilt or deviation is permissible, as long as it does not affect the normal function of the relevant component. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," not that the structure must be perfectly horizontal; a slight tilt is acceptable. "Coaxial" means that two components are set as coaxially as possible, allowing them to move coaxially or approximately coaxially when their relative positions change. Alternatively, it can be simplified to mean that the corresponding device / component / element, when set in a "horizontal," "vertical," "suspended," "parallel," or "coaxial" direction, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. For example, the deviation in the "coaxial" direction is controlled within 0.2-1mm, preferably within 0.2-0.5mm. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the solution of the present invention.

[0024] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0025] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as 2, 3, 4, 5, 6, 7, 8, or 9, and can even exceed nine.

[0026] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to common connection methods in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0027] Example 1 This embodiment provides a method for controlling the anti-skid pavement performance based on waste refractory materials. The pavement includes a wearing layer composed of recycled aggregate, which is prepared from waste refractory materials. The control method includes the following steps: S1. Obtain recycled aggregates; S2. Prepare pavement samples based on recycled aggregates. Use an accelerated abrasion tester to abrade the pavement samples at different times under a set load to obtain dynamic friction coefficient data, average cross-sectional depth data, macro-texture parameter data, and micro-texture parameter data. Based on the dynamic friction coefficient data, average cross-sectional depth data, macro-texture parameter data, and micro-texture parameters, conduct correlation analysis between different parameters and select parameters with no correlation as aggregate characteristic parameters. Prepare a mixture sample of recycled aggregate and binder, conduct dynamic modulus tests on the mixture sample at different temperatures and loading frequencies, and establish a dynamic modulus prediction model using the dynamic modulus data; S3. Based on the aggregate characteristic parameters and dynamic modulus prediction model, determine whether the pavement performance requirements are met. If not, adjust the gradation and performance parameters of the recycled aggregate and repeat steps S1 to S3 until the pavement performance requirements are met.

[0028] This embodiment selects three types of waste refractory materials to prepare recycled aggregates: silicon-mullite bricks, castables, and high-voltage electrical porcelain. Silicon-mullite bricks are constructed with a skeleton of high-grade bauxite clinker containing more than 80% Al2O3, and the matrix is ​​made of silicon carbide, alumina, and silicon dioxide. Corundum-magnesium-alumina spinel castables, or simply castables, are a type of high-alumina refractory material, commonly used in the construction of the bottom and walls of converter refining ladles. They can significantly improve the service life of the ladle, exceeding that of magnesia-carbon bricks and magnesia-alumina bricks by more than twice. Corundum-magnesia-alumina spinel castables use high-grade bauxite or corundum, magnesium oxide, and silica powder as the main raw materials, with calcium aluminate cement as the binder. The main crystalline phases are corundum and magnesia-alumina spinel. High-voltage porcelain refers to defective or substandard products generated during the production of high-voltage porcelain due to imperfect processes or unqualified testing, as well as waste materials generated during use due to damage, such as high-voltage porcelain insulators, supports, and bushings, which are damaged during performance testing or natural wear and tear. Three types of waste refractory materials were crushed to obtain recycled aggregates. The three recycled aggregates were compared with existing aggregates. The comparison aggregates selected were HFST's commonly used 88# calcined bauxite aggregate, natural wear-resistant aggregate basalt, and waste aggregate steel slag commonly used in anti-skid pavements. The six aggregates were screened for target gradation. Table 1 shows the grading requirements of high anti-skid surface aggregates and the gradation results of the six aggregates.

[0029] Table 1. Gradation requirements and results of recycled aggregates

[0030] Specifically, the anti-skid pavement also includes a base course, on which an adhesive layer and a wear layer are sequentially arranged. The pavement sample includes a base course, an adhesive layer, and a wear layer arranged sequentially. The adhesive layer is composed of an adhesive, wherein the adhesive layer uses E41 epoxy resin adhesive and a curing agent. The epoxy resin adhesive and the curing agent are mixed in a ratio of 1:1.2 and then thoroughly stirred to form an adhesive. The viscosity of the adhesive is 0.7~2.5 Pa·s, the tensile strength (25℃, 7 days) is 17~35 MPa, the elongation at break (25℃, 7 days) is 30~70%, and the elastic modulus (25℃, 7 days) is ≤900 MPa.

[0031] Pavement specimens (HFST specimens) were prepared. Two sets of HFSTs were prepared for each type of aggregate and tested in parallel. The specific preparation process of the pavement specimens is as follows: a. Preparation of the concrete base. The dimensions of the concrete base are 50×50×5cm. 3 After the base is formed, the surface of the concrete base is polished using an angle grinder to ensure that the base surface is flat and free of protrusions.

[0032] b. Weigh the six aggregates, epoxy resin, and curing agent separately. The amount of aggregate used for the surface layer of each HFST specimen is 2.13~2.30 kg, and the amount of epoxy resin and curing agent is 0.19~0.21 kg. Mix the adhesive with a stirrer for about 3 minutes.

[0033] c. Aggregate bonding process. The epoxy resin adhesive is applied using a notched neoprene scraper, and the thickness of the adhesive is controlled at 1.016~1.27mm using a wet film thickness gauge. The aggregate should be evenly spread on the epoxy resin adhesive layer, and the aggregate must cover the adhesive to ensure that there are no "wet" spots on the HFST surface.

[0034] d. After the epoxy resin adhesive has fully cured, remove excess aggregate from the HFST surface to obtain a pavement sample, such as... Figure 1 As shown.

[0035] The accelerated wear tester used a three-wheel accelerated wear tester (TWPD) to simulate the long-term anti-skid attenuation process of road surface samples. The TWPD weighed 100 kg, and rubber wheels were used for testing. To ensure that the wear area on the HFST specimen surface was consistent with the rotation measurement area of ​​the DFT turntable, the wear wheel track was a ring with a diameter of 284 mm. The contact area between the tire and the HFST specimen was 11.55 cm², the tire pressure was set to 0.7 MPa, the load weight of the TWPD was 243 kg, and the spindle speed was 25 r / min. One wear cycle consisted of 10,000 cycles, and a set of samples underwent 14 wear cycles, for a total of 140,000 wear cycles. According to the requirements of ASTM E1911-09, the dynamic friction coefficient of the HFST surface at 40 km / h and 60 km / h was tested using a JDF-08 dynamic friction coefficient tester, and the results are expressed as follows: μ 40 , μ 60 After each wear cycle, the crushed aggregate on the HFST surface is first cleaned up, and an AMES pavement texture laser scanner is used to obtain the three-dimensional surface morphology of the HFST. The average cross-sectional depth (MPD) of the scanned area is calculated based on the elevation measurement values ​​after each wear cycle.

[0036] The decay process of the dynamic friction coefficient is as follows: Figure 2 As shown in Table 2, the final DF values ​​of HFST are listed. The dynamic friction coefficient of most aggregates reaches the final wear value after the 10th cycle. In this experiment, the accelerated wear test cycle was adjusted to 14 cycles to differentiate the anti-slip performance of high wear-resistant aggregates.

[0037] Table 2 Final values ​​of dynamic friction coefficient for HFST of different aggregates

[0038] The data in the figure shows that the HFST decay process mainly includes three stages: accelerated decay, gradual decay, and a stable stage. The final DF values ​​of each aggregate are ranked as follows: calcined bauxite > silica-mullite brick > high-voltage electrical porcelain > basalt > castable > steel slag. Among them, the anti-skid property of silica-mullite brick is 90% of that of calcined bauxite, which is significantly higher than that of other high-alumina recycled wear-resistant aggregates. 40 The final value was 1.4 times that of basalt and castable. This is related to the mineral composition and texture of the silica-mullite brick, which has a high content of Al2O3 and SiC, both of which contribute to the wear resistance of the aggregate. HFST using basalt aggregate exhibited good anti-skid properties in the first 1-5 cycles, but its attenuation rate was significantly higher than that of castable and high-voltage porcelain. In the first five cycles, basalt showed higher anti-skid properties than castable and high-voltage porcelain, while in the later stages of wear, the μ values ​​of the three aggregates decreased. 40 and μ 60As the difference in friction decreases, the skid resistance of the three aggregates at the end of the wear stage is ranked as follows: high-voltage electrical porcelain > basalt > castable. As alternative aggregates to HFST, castable and high-voltage electrical porcelain can achieve skid resistance levels comparable to basalt and can be applied to road sections and longitudinal slopes with lower skid resistance requirements. Steel slag exhibits only 48% of the skid resistance of calcined bauxite in HFST, showing poor long-term skid resistance. During the gradual decay phase of 5-10 cycles, its dynamic friction coefficient decreases faster than the other five aggregates. The worn aggregates show a noticeable luster, and their skid resistance does not meet the skid resistance standards for HFST pavements.

[0039] Loss rate and decay rate are used as evaluation indicators for anti-skid performance degradation. The former refers to the loss rate of dynamic friction coefficient and MPD after 10 wear cycles, respectively, expressed as Δμ / μ 初始值 and ΔMPD / MPD 初始值 The latter refers to the dynamic friction coefficient and MPD decay rate of HFST after three-wheel wear tests, expressed as Δμ / 10 cycles and ΔMPD / 10 cycles, respectively. At a simulated speed of 40 km / h, μ... 40 The loss rate and attenuation rate are shown in Table 3.

[0040] Table 3 μ 40 loss rate and decay rate

[0041] As can be seen from the table, the μ values ​​of calcined bauxite and silica-mullite bricks, castables, and high-voltage electrical porcelain... 40 The low loss rate and attenuation rate are related to the high alumina content of the aggregates. The presence of alumina slows down the decline in the anti-slip properties of the aggregates, allowing them to maintain a relatively stable coefficient of friction in the later stages of wear. Among the six aggregates, basalt and steel slag aggregates have the highest μ... 40 The highest loss rate and attenuation rate indicate that the anti-skid properties of both aggregates decrease significantly in the later stages of wear, with the aluminum aggregate exhibiting higher long-term anti-skid performance and lower performance.

[0042] The decay process of MPD for six HFSTs is as follows Figure 3 As shown in Table 4, the loss rate and decay rate of MPD are also shown.

[0043] Table 4 MPD Loss Rate and Attenuation Rate

[0044] Based on the above data, the initial MPD values ​​of the six HFSTs showed some differences, mainly due to slight variations in aggregate particle size. Before the experiment, the crushed aggregates underwent multiple sieving processes to minimize experimental errors caused by particle size differences. The MPD of the six HFSTs decreased rapidly within 1-5 cycles. During the gradual decay phase from 5-10 cycles, the MPD values ​​of the aggregates remained relatively stable, but fluctuations of varying degrees occurred. This was because, during the abrasion process, the weaker parts of the aggregates were crushed and detached, creating a height difference with the harder parts, thus causing fluctuations in the MPD values. After 10 cycles, the MPD of the HFSTs essentially stopped changing and entered a stable phase.

[0045] Calcined bauxite and silica-mullite bricks exhibited the lowest MPD loss rate, consistent with their excellent anti-skid properties. Basalt, high-voltage electrical porcelain, and steel slag showed higher MPD loss and decay rates, indicating faster decay of their macroscopic texture and poorer long-term anti-skid performance compared to other aggregates. The MPD decay rate of high-voltage electrical porcelain was related to its higher needle-like and flaky content.

[0046] For the correlation analysis of anti-skid performance indicators, μ(n) = A·exp(B·n) was selected as the friction coefficient decay prediction model. The friction coefficient decay curves of HFST with different aggregates were fitted, where A is the weighting coefficient, B is the rate of change, and n is the wear cycle. The μ(n) of HFST... 40 and μ 60 The fitting formulas are shown in Table 5, where μ 40 Correlation analysis with wear cycle, such as Figure 4 As shown. Among the fitting formulas for the six aggregates, calcined bauxite and silica-mullite bricks showed the lowest rates of change, indicating that the μ values ​​of these two aggregates were relatively low. 40 The lowest decay rate and excellent long-term anti-skid properties were observed in calcined bauxite and silica-mullite bricks. Their weighting coefficient A was relatively high among the six aggregates, indicating that calcined bauxite and silica-mullite bricks exhibited the best anti-skid properties. Steel slag and basalt had the highest rate of change, indicating that these two aggregates had the fastest rate of anti-skid decay. Castables and high-voltage electrical porcelain had rate of change in the middle, with decay rates lower than steel slag and basalt.

[0047] Table 5 μ of HFST 40 and μ 40 Fitting formula

[0048] The influence of macroscopic texture parameters on the skid resistance of antiskid pavements prepared from recycled aggregates was analyzed. Figures 5-10 The wheel travel trajectory diagrams and local wheel track diagrams of HFST specimens made of six aggregates, including calcined bauxite, after 140,000 wear cycles are shown.

[0049] according to Figure 10In the final stage of wear, the anti-skid properties of the aggregate are basically stable, and the macroscopic texture no longer undergoes significant changes. Figures 5-10 As can be seen, a visible height difference exists between the aggregate in the local wheel tracks and the surrounding unworn aggregate. In some areas, the aggregate has been worn down, which is quite obvious. Figure 7 (b) shows the local trajectory of the steel slag. It can be seen from the figure that the worn steel slag aggregate not only showed local flattening, but also a large amount of steel slag showed a metallic luster. This is also the reason why the steel slag has poor anti-skid performance in HFST pavement.

[0050] Macro-texture is a large-scale texture formed by aggregate particles on the HFST surface, influenced by parameters such as aggregate gradation, size, and shape. Macro-texture determines the anti-skid performance of road surfaces at speeds above 40 km / h. It also provides surface drainage paths for water to escape from the contact area between the tire and the road surface, preventing high-speed skidding. The AMES road texture laser scanner can also reflect a more realistic road surface texture through the reconstruction of the road's three-dimensional structure. To minimize testing errors, the scanning area was fixed within a 3cm × 3cm region within the tire track during testing. Figure 11 This is a 3D scan of different HFSTs before wear. Different colors represent different heights; the green raised areas represent aggregates on the HFST surface, while the blue areas represent epoxy resin binder. HFSTs have rich macroscopic textures, with an average MPD of 1.097~1.731 mm before wear.

[0051] Compared to the non-wearing state, after 140,000 wear cycles, as Figure 12 The MPD of HFST decreased to 0.347~1.003mm. During the abrasion process, the macroscopic texture became smoother, and the dense peaks gradually disappeared, indicating that the aggregate was abraded and compacted, and the proportion of protruding aggregates decreased significantly.

[0052] The planar plot of HFST is obtained by quantitatively describing the changes in macroscopic texture and aggregate distribution, corresponding to the 3D image. In the planar plot, "1" represents protruding aggregate, "2" represents epoxy resin binder, "3" represents protruding aggregate with high MPD in region 1, and "4" represents abraded aggregate and detached particles with low MPD. For calcined bauxite and silica-mullite bricks, after 100,000 abrasion cycles, the protruding aggregate is uniformly distributed throughout the scanned area. The protruding aggregate of castables is sporadically distributed in the scanned area after abrasion. The image was processed using IPP software (version 6.0) and the area of ​​protruding aggregate within the scanned area was calculated, along with its area ratio within the entire test area. The protruding area ratio of the six aggregates is as follows: Figure 13As shown, calcined bauxite and silica-mullite bricks have the highest proportion of prominent aggregate area, indicating that they have good macroscopic texture. The area ratios of basalt, castable, and high-voltage electrical porcelain range from 10.38% to 17.59%; steel slag has the lowest area ratio at 5.12%, indicating that the aggregate is basically worn down at the end of the wear process, resulting in the worst macroscopic texture.

[0053] The macro- and micro-morphological features of the HFST specimen surface before and after wear were extracted using AMES, yielding surface roughness indices such as Ra, Rq, and Rsk. The arithmetic mean deviation of the profile (Ra) is the average absolute value of the deviation of the profile amplitude relative to the centerline within the scanning area. The root mean square deviation of the profile (Rq) represents the root mean square value of all profile offsets along the reference length direction. The slope (Rsk) is used to evaluate the symmetry of the probability density function curve dispersion of the profile amplitude. The test results of each texture index were obtained through morphological distribution analysis of the specimen surface before and after wear, as shown in Table 6. Figure 14 The variation trends of HFST texture parameters Ra, Rq, and Rsk with the wear process.

[0054] Table 6 Test results of various texture indices on the surface of the specimens before and after wear.

[0055] Before 100,000 cycles of accelerated loading and abrasion, the fluctuations in various texture indices were most pronounced. After 100,000 cycles, the changes in aggregate texture indices tended to level off and gradually reached their final values. The decrease in texture indices Ra and Rq indicates that the geometric height of the HFST surface texture significantly decreased after abrasion. Among them, calcined bauxite and silica-mullite bricks showed the largest decreases in Ra and Rq texture indices, while high-voltage porcelain and steel slag showed the smallest decreases, with castable and basalt falling in between. The decrease in the absolute value of the texture index skewness (Rsk) indicates that the distribution of surface profile peaks and valleys changed accordingly after abrasion. The Rsk indices of the six aggregates were basically below 0 before and after abrasion, indicating that the pavement profile peaks were wide and the profile valleys were sharp. With the increase of the number of load cycles, Rsk tended to increase, indicating that the surface texture of HFST had different degrees of wear. The fluctuations were the largest in the first five abrasion cycles, and after five cycles, the fluctuations gradually leveled off. Among the six types of aggregates, steel slag aggregate has the highest Rsk index, all of which are above 0. The aggregate has sharp profile peaks and wide and flat profile valleys, indicating that the load has the greatest wear effect on the aggregate.

[0056] To characterize the dynamic friction coefficient μ 40 To investigate the relationship between different texture indices, the Pearson correlation coefficient was used to analyze the correlation between the indices. The formula for calculating the Pearson correlation coefficient is shown in equation (1). μ was calculated using SPSS statistical software. 40The correlation of five indicators, MPD, Ra, Rq, and Rsk, after 50,000, 80,000, and 100,000 wear cycles, and the calculation results of the Pearson correlation coefficient are shown in Table 7.

[0057] (1) Where: n—sample size; xi, yi—sample variables; , —Sample mean.

[0058] Table 7. Calculation results of the correlation between various indicators for different wear cycles.

[0059] Note: *At the 0.05 level, the correlation is significant; **At the 0.01 level, the correlation is significant.

[0060] From the above results, we can see that μ 40 There are certain correlations among MPD, Ra, and Rq. Among them, MPD has a high correlation with Rq and Ra, and Rq has a higher correlation than Ra, indicating good correlation among the three texture indices. One or more of these indices can be selected for macroscopic texture analysis. Rsk and μ 40 The correlations between μ, MPD, Ra, and Rq are all poor, indicating that Rsk characterizes different features of surface texture. To clarify μ... 40 The relationships between MPD, Ra, and Rq were analyzed using regression analysis on data from 10,000 to 100,000 and 140,000 wear cycles. The established relationships are as follows: Figure 15 As shown.

[0061] As can be seen from the figure, μ 40 The linear correlation with MPD is quite obvious, R 2 =0.65, μ 40 The correlation between R and Rq is not significant. 2 =0.56. The correlation between MPD and Rq is good, R... 2 =0.62, indicating that the two texture indices describe the macroscopic texture of HFST quite consistently. Ra and Rq show a significant correlation, and R... 2 =0.9. When evaluating the macroscopic texture of HFST, either of the two metrics can be selected.

[0062] Road surface skid resistance is related not only to the macroscopic texture of aggregates but also closely to their microscopic texture; both textures jointly influence road surface skid resistance. Microscopic texture is generated by the surface roughness of aggregate particles, and its magnitude depends on the initial surface roughness of the aggregates and the ability of the aggregates to maintain this roughness after polishing. Figure 16The images show scanning electron microscope (SEM) images of six aggregates before and after wear at the same scale. As can be seen from the images, the surface texture of the aggregates tends to be smoother after wear. The surfaces of steel slag and high-voltage porcelain are the smoothest, followed by castables and basalt. Calcined bauxite and silica-mullite bricks have the most similar surfaces, with a relatively dense structure and high roughness.

[0063] To more clearly characterize and quantify the surface roughness of the aggregates, a 3D laser microscope was used to test the aggregate roughness before and after wear. Surface roughness images and cross-sectional depth curves within the test areas for six types of aggregates are shown below. Figure 17-22 As shown, the surface roughness of the aggregate before and after wear. Sa The results are as follows Figure 23 As shown.

[0064] As shown in the figure, the initial surface roughness of the six aggregates... Sa The order of size is: silica-mullite brick > basalt > steel slag > castable > calcined bauxite > high-voltage electrical porcelain. The surface texture of the aggregates became smoother after abrasion. The surface roughness of the six aggregates decreased by 12.9%, 68.9%, 91.01%, 47.1%, 65.5%, and 2.3% respectively after abrasion. (Surface roughness after abrasion) Sa The order of size is: silica-mullite brick > calcined bauxite > high-voltage electrical porcelain > basalt > castable > steel slag. This shows that the microtexture after wear and the ability of the aggregate to retain its microtexture are directly proportional to its anti-skid performance. When evaluating the anti-skid level of aggregates, their microtexture is indispensable. After wear, the surfaces of calcined bauxite and silica-mullite bricks still exhibit significant protrusions, with surface roughness reaching 69.58 μm and 100.32 μm, respectively, which are 5.8 to 8.3 times that of steel slag. This is consistent with the SEM test results, indicating that both aggregates can still maintain good microtexture after long-term wear testing.

[0065] Dynamic modulus is one of the fundamental properties of materials and a basic parameter for stress analysis and numerical simulation of anti-slip layers. Therefore, the dynamic modulus of the epoxy resin-recycled aggregate mixture was tested according to the AASHTO T342 method.

[0066] In this embodiment, three mixed samples with a diameter of 100 mm and a height of 150 mm were used to measure the dynamic modulus, namely Den-1, Den-2 and Den-3. The specimen size and apparent density are shown in Table 8. The water absorption rate of the epoxy resin and recycled aggregate mixture is only 0.02%, so the anti-slip layer can be considered as a non-absorbent material.

[0067] Table 8 Specimen Dimensions and Apparent Density

[0068] Note: (1) Apparent density of the specimen at 25℃.

[0069] The dynamic modulus test of the epoxy resin and recycled aggregate mixture was conducted at four different test temperatures (−10℃, 4℃, 21℃, and 37℃) and six different loading frequencies (25 Hz, 10 Hz, 2 Hz, 1 Hz, 0.5 Hz, and 0.1 Hz). Table 9 shows the dynamic modulus test results. The phase angle can be used to distinguish the elastic and viscous characteristics of the material: a phase angle of 0° indicates an ideal elastic material; a phase angle of 90° indicates an ideal viscous material; and a phase angle between 0° and 90° indicates a viscoelastic material. Table 9 shows that at -10℃, when the loading frequency increases from 0.1 Hz to 25 Hz, the dynamic modulus and phase angle do not change significantly; the corresponding phase angle is no greater than 2.52°, indicating that the epoxy resin and recycled aggregate mixture is an elastic material at this temperature. However, as temperature increases, the dynamic modulus gradually decreases, while the phase angle gradually increases. The elastic characteristics of the epoxy resin and recycled aggregate mixture weaken, while the viscous characteristics increase. When the temperature reaches 37°C, the phase angle ranges from 20° to 45°, which is much larger than the phase angle at -10°C. Simultaneously, the load frequency has an increasingly greater impact on the dynamic modulus and phase angle. Therefore, the epoxy resin and recycled aggregate mixture is a viscoelastic material whose mechanical properties are temperature-dependent, exhibiting a high low-temperature modulus and a low high-temperature modulus.

[0070] Table 9 Dynamic Modulus Test Results

[0071] Figure 24 The dynamic modulus curve of the epoxy resin and recycled aggregate mixture at 21℃ is shown, which can be characterized by equations (2) and (3). The six fitting parameters of equations (2) and (3) can be determined by numerical optimization, that is, by solving for the minimum value of the sum of squared errors according to equation (4). It is calculated that when α, β, γ, δ, a1 and a2 are 6.636, -2.715, -3.182, -0.364, 0.019 and 0.00029 respectively, The minimum value is 0.0017. Based on equations (2) and (3) and the above six fitting parameters, the dynamic modulus corresponding to any temperature and load frequency can be calculated, which also provides basic data support for further in-depth stress analysis of the anti-slip layer.

[0072] (2) (3)

[0073] In the formula: It is the dynamic modulus, psi; It's a frequency reduction, in Hz; It is the load frequency, in Hz; T and T represent the reference temperature and the test temperature, respectively. o C; α, β, γ, δ, a1, and a2 are the fitting parameters; It is the sum of squared errors; It is the logarithm of the dynamic modulus predicted according to equations (2) and (3); It is the logarithm of the measured mean of the dynamic modulus; n It is the number of combinations of test temperature and load frequency.

[0074] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for controlling the performance of anti-skid pavement based on waste refractory materials, wherein the anti-skid pavement includes a wearing layer, characterized in that, The wear layer is composed of recycled aggregate, which is prepared from waste refractory materials. The control method includes the following steps: S1. Obtain the recycled aggregate; S2. Prepare road surface samples based on the recycled aggregate, and use an accelerated loading abrasion tester to abrade the road surface samples for different numbers of times under a set load to obtain dynamic friction coefficient, average cross-sectional depth, macro-texture parameters and micro-texture parameters; perform correlation analysis between different parameters based on dynamic friction coefficient, average cross-sectional depth, macro-texture parameters and micro-texture parameters, and select parameters with no correlation as aggregate characteristic parameters; Prepare a mixture sample of the recycled aggregate and binder, and conduct dynamic modulus tests on the mixture sample at different temperatures and loading frequencies. Use the dynamic modulus data to establish a dynamic modulus prediction model. S3. Based on the aggregate characteristic parameters and the dynamic modulus prediction model, determine whether the recycled aggregate meets the pavement performance requirements. If not, adjust the gradation and performance parameters of the recycled aggregate, and repeat steps S1 to S3 until the pavement performance requirements are met.

2. The method for controlling the anti-skid pavement performance based on waste refractory materials according to claim 1, characterized in that, The waste refractory materials include at least one of silica-mullite bricks, corundum-magnesium-aluminum spinel castables, and high-voltage electrical porcelain.

3. The method for controlling the anti-skid pavement performance based on waste refractory materials according to claim 1, characterized in that, The macroscopic texture parameters include the arithmetic mean deviation of the profile, the root mean square deviation of the profile, and the skewness, while the microscopic texture parameters include surface roughness.

4. The method for controlling the anti-skid pavement performance based on waste refractory materials according to claim 1, characterized in that, In step S2, for the dynamic friction coefficient data, a friction coefficient decay prediction model is established. The friction coefficient decay prediction model is as follows: μ(n) = A·exp(B·n) Where μ is the dynamic friction coefficient, A is the weighting coefficient, B is the rate of change, and n is the wear cycle.

5. The method for controlling the anti-skid pavement performance based on waste refractory materials according to claim 1, characterized in that, In step S2, the correlation analysis of dynamic friction coefficient, average cross-sectional depth, macro-texture parameters and micro-texture parameters is performed by calculating the Pearson correlation coefficient to analyze the correlation between different parameters.

6. The method for controlling the anti-skid pavement performance based on waste refractory materials according to claim 5, characterized in that, In correlation analysis, when the correlation coefficient R0 2 A correlation coefficient greater than 0.6 indicates that the two parameters are correlated. 2 If the value is ≤0.6, it means that the two parameters are not correlated.

7. A method for controlling the anti-skid pavement performance based on waste refractory materials according to any one of claims 1-6, characterized in that, The anti-skid pavement also includes a base layer, on which an adhesive layer and a wear layer are sequentially disposed.

8. The method for controlling the anti-skid pavement performance based on waste refractory materials according to claim 7, characterized in that, The road surface sample includes the base layer, the bonding layer and the wear layer arranged in sequence, wherein the base layer is a concrete structure.

9. A method for controlling the anti-skid pavement performance based on waste refractory materials according to any one of claims 1-6, characterized in that, The mixture sample is a cylindrical structure with a diameter of 5-20 cm and a height of 10-25 cm.

10. A recycled aggregate based on waste refractory materials, characterized in that, The recycled aggregate is obtained using the anti-skid pavement performance control method based on waste refractory materials as described in any one of claims 1-9.

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