Optimization design method of asphalt pavement structure based on mechanical parameter analysis

Abstract

The application discloses a kind of based on mechanical parameter analysis's asphalt pavement structure optimization design method, steps include: S01.Configuration initial pavement structure and configuration cement stabilized macadam cement dosage, asphalt mixture asphalt dosage range of value;S02.Establish the correlation model between the mechanical parameters of cement stabilized macadam and asphalt mixture and cement dosage and asphalt dosage;S03.Determine multiple different pavement structure material mix proportion combinations in the configured range of value, and corresponding mechanical parameters are determined according to correlation model under different pavement structure material mix proportion combinations;S04.The mechanical response analysis is carried out to the mechanical parameters determined under each pavement structure material mix proportion combination, and the optimal pavement structure material mix proportion combination is determined according to mechanical response analysis.The application can make the mechanical properties of pavement structure optimal, and match with the real mechanical response of pavement.

Description

Technical Field

[0001] This invention relates to the field of pavement structure optimization design technology, and in particular to an asphalt pavement structure optimization design method based on mechanical parameter analysis. Background Technology

[0002] Currently, road surface design is usually achieved using the traditional linear elastic theory (i.e., single modulus theory). This means that the compressive resilient modulus is used as the material stiffness parameter during the design. However, the compressive and tensile moduli of road materials can have significant differences. This type of single modulus theory road surface structure design does not fully consider the significant differences in the compressive and tensile moduli of the road material, and therefore does not match the actual stress characteristics of the road surface.

[0003] Using bimodulus theory-based pavement mechanics analysis methods, which align with the tensile and compressive properties of pavement materials, is beneficial for obtaining the true stress-strain state of the pavement. However, in current pavement structure design methods based on bimodulus theory, the compressive and tensile mechanical parameters and their ratios of pavement materials are usually selected based on experience or directly according to the ranges given in the specifications, without considering the quantitative relationships between the various mechanical parameters of the materials. This makes it impossible to accurately adjust (match) the values. The selection of compressive and tensile mechanical parameters and their ratios of pavement materials directly affects the mechanical response calculation results. Mismatched values ​​may lead to significant deviations in the calculation results. Therefore, the material parameters determined by the current bimodulus theory-based pavement structure design methods often differ significantly from the actual mechanical performance parameters of the materials, making it difficult for the pavement structure to strictly adhere to integrated design. Ultimately, this results in unreliable pavement structure calculation results and pavement service life that fails to meet design requirements. Summary of the Invention

[0004] The technical problem to be solved by this invention is: in view of the technical problems existing in the prior art, this invention provides an asphalt pavement structure optimization design method based on mechanical parameter analysis, which is simple to implement, has high design accuracy and reliability of pavement structure, and has small error, and can make the mechanical performance of the pavement structure reach the optimal level and match the actual mechanical response of the pavement.

[0005] To solve the above-mentioned technical problems, the technical solution proposed by this invention is as follows: A method for optimizing the design of asphalt pavement structures based on mechanical parameter analysis, comprising the following steps: S01. Configure the initial pavement structure and the range of values ​​for cement dosage of cement stabilized crushed stone and asphalt content of asphalt mixture. S02. Establish a correlation model between the mechanical parameters of cement-stabilized crushed stone and asphalt mixtures and the cement dosage and asphalt content. The mechanical parameters include tensile and compressive modulus and tensile and compressive Poisson's ratio. The tensile and compressive modulus includes compression modulus and tensile modulus. The tensile and compressive Poisson's ratio includes compression Poisson's ratio and tensile Poisson's ratio. S03. Within the configured range of values, determine a variety of different pavement structure material mix proportions, and under different pavement structure material mix proportions, determine the corresponding mechanical parameters according to the correlation model. The pavement structure material mix proportions are mix proportions formed by different asphalt dosages and different cement dosages. S04. Perform mechanical response analysis on the mechanical parameters obtained under each combination of pavement structure materials mix proportions, and determine the optimal combination of pavement structure materials mix proportions based on the mechanical response analysis.

[0006] Furthermore, configuring the initial pavement structure in step S01 includes configuring the cement-stabilized crushed stone base asphalt pavement structure type, structural layer thickness, and the material type and gradation of each component in the cement-stabilized crushed stone and asphalt mixture in the pavement structure layer.

[0007] Furthermore, the configuration value range also includes the value ranges for temperature and loading rate.

[0008] Furthermore, in step S02, the relationship between the tensile modulus and tensile Poisson's ratio and the asphalt content and cement content is determined by modulus and Poisson's ratio tests under compression and tensile stress states, respectively. The relationship is then fitted and regressed to establish a functional relationship model, thereby obtaining the correlation model between the tensile modulus and tensile Poisson's ratio of cement-stabilized crushed stone and cement content, as well as the correlation model between the tensile modulus and tensile Poisson's ratio of asphalt mixture and asphalt content.

[0009] Furthermore, the correlation model between the tensile and compressive modulus and Poisson's ratio of the cement-stabilized crushed stone and the cement dosage is as follows:

[0010] in, M For cement dosage, , , These are the fitting parameters;

[0011] in, , , These are the fitting parameters; The correlation model between the tensile and compressive modulus and Poisson's ratio of the asphalt mixture and the asphalt content is as follows:

[0012] in, This refers to the amount of asphalt used. , , These are the fitting parameters;

[0013] in, , , These are the fitting parameters.

[0014] Furthermore, the determination of the relationship between the compressive and tensile moduli and Poisson's ratio as a function of asphalt content and cement dosage through the modulus and Poisson's ratio tests under compressive and tensile stress states includes: before the test, fixing the extensometer to the pre-marked scale positions on both sides of the specimen and then placing it on the MTS testing system; selecting the stress control mode; performing multi-stage loading and unloading on the asphalt mixture and cement-stabilized crushed stone respectively; the magnitude of each load stage is a specified proportion of the maximum destructive load; pausing for a specified time after unloading each load stage before the next loading is performed; and recording the strain magnitude during the loading and unloading process; and calculating the uniaxial compressive and direct tensile moduli based on the test results.

[0015] Furthermore, the calculation expressions for uniaxial compressive modulus, direct tensile modulus, uniaxial compressive-tensile Poisson's ratio, and direct tensile Poisson's ratio are as follows:

[0016]

[0017]

[0018] in, It is the uniaxial compressive modulus. For direct tensile modulus, For each stage of compressive and tensile load during uniaxial compression, For each stage of compressive and tensile load during direct tension, This represents the vertical springback strain under uniaxial compression. Vertical springback strain during direct tension For uniaxial compression or direct tension vertical springback strain, For uniaxial compression or direct tension, the lateral springback strain is... For uniaxial compression or direct stretching, Poisson's ratio, b The width of the direct tensile test specimen for asphalt mixture. h To directly stretch the height of the specimen, d The diameter is the diameter of the uniaxial compression specimen of the asphalt mixture.

[0019] Furthermore, in step S04, the mechanical response analysis is performed using a pavement structure design and finite element analysis method based on bimodulus theory.

[0020] Furthermore, in step S04, the mechanical response analysis includes analyzing the horizontal tensile strain at the bottom of the asphalt mixture layer along the driving direction, the horizontal tensile stress at the bottom of the inorganic binder stabilized layer along the driving direction, the vertical compressive stress on the top surface of each layer of the asphalt mixture layer, and the vertical compressive strain on the top surface of the subgrade. Based on the pavement structure, the maximum mechanical response value of the corresponding category mechanical response calculation point is taken, and the combination corresponding to the minimum maximum mechanical response value is selected as the optimal pavement structure material mix ratio combination.

[0021] Furthermore, in step S04, when performing mechanical response analysis, the following correction formula is also included:

[0022] in, , These are the uniaxial compressive modulus and the direct tensile modulus, respectively. , These are the uniaxial compression Poisson's ratio and the direct tension Poisson's ratio, respectively.

[0023] Compared with the prior art, the advantages of the present invention are as follows: 1. This invention is based on the concept of integrated material and structure design. It considers the influence of cement dosage and asphalt content on the mechanical parameters of pavement materials. By obtaining the mechanical parameters of materials, a correlation model between the mechanical parameters and the changes in cement dosage and asphalt content is established. Then, mechanical response analysis is performed on the mechanical parameters under different combinations of cement dosage and asphalt content. Based on the analysis results, the optimal mix ratio combination is determined. This can provide an accurate quantitative range of values ​​for the selection of mechanical parameters when designing pavement structures based on the dual-modulus theory, so that the mechanical performance of the pavement structure reaches the optimal level. 2. This invention fully considers the differences in tensile and compressive modulus, and uses a correlation model between mechanical parameters and changes in cement dosage and asphalt dosage to determine the optimal mix ratio of materials. This can reflect the true mechanical response of the pavement, so that the selected material parameters match the true mechanical properties of the materials, effectively improving the rationality and reliability of pavement structure design, and thus increasing the service life of the pavement. Attached Figure Description

[0024] Figure 1 This is a schematic diagram illustrating the implementation process of the asphalt pavement structure optimization design method based on mechanical parameter analysis in this embodiment.

[0025] Figure 2 This is a schematic diagram of the gradation curve of cement-stabilized crushed stone in a specific application embodiment of the present invention.

[0026] Figure 3 This is a schematic diagram of the gradation curve of asphalt mixture in a specific application embodiment of the present invention. Detailed Implementation

[0027] The present invention will be further described below with reference to the accompanying drawings and specific preferred embodiments, but this does not limit the scope of protection of the present invention.

[0028] like Figure 1 As shown, the steps of the asphalt pavement structure optimization design method based on mechanical parameter analysis in this embodiment include: S01. Initial pavement structure configuration: Configure the initial pavement structure according to actual needs, and configure the range of values ​​for cement dosage of cement stabilized crushed stone and asphalt content of asphalt mixture.

[0029] Configuring the initial pavement structure specifically includes configuring the type of cement-stabilized crushed stone base asphalt pavement structure, the thickness of the structural layers, and the material types and gradations of each component in the cement-stabilized crushed stone and asphalt mixture within the pavement structural layers. It also involves configuring the range of values ​​for the cement dosage of the cement-stabilized crushed stone and the asphalt content of the asphalt mixture. Further configuration includes the range of values ​​for related parameters such as temperature and loading rate. These ranges can be initially set based on actual needs and relevant specifications (such as the "Specifications for Design of Highway Asphalt Pavement").

[0030] S02. Correlation Model Establishment: Establish a correlation model between the mechanical parameters of cement-stabilized crushed stone and asphalt mixture and the cement dosage and asphalt content. The mechanical parameters specifically include tensile and compressive moduli and tensile and compressive Poisson's ratios. The tensile and compressive moduli include compression modulus and tensile modulus, and the tensile and compressive Poisson's ratios include compression Poisson's ratio and tensile Poisson's ratio, so as to realize pavement mechanical analysis based on the dual modulus theory.

[0031] In this embodiment, the relationship between the tensile modulus and tensile Poisson's ratio and the asphalt content and cement content is determined by modulus and Poisson's ratio tests under compressive and tensile stress states, respectively. The relationship is then fitted and regressed to establish a functional relationship model, resulting in the correlation model between the tensile modulus and tensile Poisson's ratio of cement-stabilized crushed stone and cement content, as well as the correlation model between the tensile modulus and tensile Poisson's ratio of asphalt mixture and asphalt content.

[0032] The above-mentioned determination of the relationship between the compressive and tensile moduli and Poisson's ratio as a function of asphalt content and cement dosage through modulus and Poisson's ratio tests under compressive and tensile stress states specifically includes: before the test, the extensometer is fixed to the pre-marked scale positions on both sides of the specimen and then placed on the MTS (Mechanical Testing and Simulation) test system. The stress control mode is selected, and multi-stage loading and unloading are performed on the asphalt mixture and cement-stabilized crushed stone respectively. The magnitude of each load stage is a specified proportion of the maximum destructive load. After each load stage is unloaded, a specified time is paused before the next loading is performed, and the strain magnitude during loading and unloading is recorded. The uniaxial compressive and direct tensile moduli are calculated based on the test results. That is, the uniaxial compressive and direct tensile moduli are obtained through the above-mentioned tests.

[0033] In a specific application embodiment, the detailed operating procedure for conducting strength, modulus, and Poisson's ratio tests under compressive and tensile stress states is as follows: The extensometer was fixed to the pre-marked positions on both sides of the specimen using a fast-curing adhesive. It was then placed on the MTS testing system, and the stress control mode was selected. For the asphalt mixture, a seven-stage loading and unloading process was employed, with each stage load being 0.1 times the maximum failure load. P m 0.2 P m 0.3 P m 、…、0.7 P m After unloading, the loading process is paused for a specified period before proceeding with the next loading cycle. For cement-stabilized crushed stone, a five-stage loading and unloading process is employed, identical to the process described above for asphalt mixtures. Strain magnitudes are recorded in real-time during the loading and unloading process. The uniaxial compression and direct tensile moduli are then calculated using the origin correction method.

[0034] In specific application embodiments, the uniaxial compression Poisson's ratio and the direct tension Poisson's ratio are calculated using the ratio of vertical strain to transverse strain at 0.5 μm, and the calculation expression is as follows: (1) (2) (3) in, It is the uniaxial compressive modulus (MPa). It is the direct tensile modulus (MPa). This represents the tensile load (N) per stage during uniaxial compression. The tensile and compressive load (N) per stage during direct tension. This represents the vertical springback strain under uniaxial compression. This represents the vertical springback strain during direct tension. For uniaxial compression or direct tension vertical springback strain, For uniaxial compression or direct tension, the lateral springback strain is... For uniaxial compression or direct stretching, Poisson's ratio, b Width (mm) of direct tensile specimen for asphalt mixture. h The height of the direct tensile specimen (mm) d The diameter (mm) of the asphalt mixture uniaxial compression specimen.

[0035] In a specific application embodiment, the expression for the correlation model between the tensile and compressive modulus and tensile and compressive Poisson's ratio of cement-stabilized crushed stone and the cement dosage is as follows: (4) in, M For cement dosage, , , These are the fitting parameters; (5) in, , , These are the fitting parameters; The specific expressions for the correlation model between the tensile and compressive moduli and tensile and compressive Poisson's ratio of asphalt mixtures and the asphalt content are as follows: (6) in, Asphalt content (%) , , These are the fitting parameters; (7) in, , , These are the fitting parameters.

[0036] By conducting multiple sets of mechanical parameter tests and analyzing the test data, correlation models were obtained between the mechanical parameters of cement-stabilized crushed stone and asphalt mixtures and the cement dosage and asphalt content (correlation models of tensile and compressive modulus and tensile and compressive Poisson's ratio of cement-stabilized crushed stone and cement dosage, and correlation models of tensile and compressive modulus and tensile and compressive Poisson's ratio of asphalt mixtures and asphalt content). Using these correlation models, the correlation between the mechanical parameters of cement-stabilized crushed stone and asphalt mixtures and the cement dosage and asphalt content can be accurately characterized, thereby facilitating the precise determination of the optimal mix proportion parameters.

[0037] S03. Determination of mechanical parameters of mix proportion combination: Within the range of configured values, various mix proportion combinations of pavement structure materials are determined, and the corresponding mechanical parameters are determined according to the correlation model under different mix proportion combinations of pavement structure materials. The mix proportion combination of pavement structure materials is a mix proportion combination formed by different asphalt dosage and different cement dosage.

[0038] Specifically, based on actual needs, within the range of cement dosage and asphalt dosage values, each asphalt dosage can be combined with different cement dosages to obtain different pavement structure material mix proportions. Then, according to the correlation model between the mechanical parameters of cement-stabilized crushed stone and asphalt mixture obtained in step S02 and cement dosage and asphalt dosage, the compression modulus, tensile modulus, compression Poisson's ratio, and tensile Poisson's ratio of each different mix proportion combination can be determined.

[0039] S04. Optimal mix proportion combination analysis: Perform mechanical response analysis on the mechanical parameters obtained under each mix proportion combination of pavement structure materials, and determine the optimal mix proportion combination of pavement structure materials based on the mechanical response analysis.

[0040] Specifically, the pavement structure design and finite element analysis method based on the dual modulus theory is used to perform mechanical response analysis on the mechanical parameters (compression modulus, tensile modulus, compression Poisson's ratio, and tensile Poisson's ratio) determined under different mix proportions. The analysis results can truly reflect the mechanical response of the pavement. Based on the mechanical response analysis results, the optimal mix proportion of pavement structure materials can be determined. This can provide an accurate range of values ​​for selecting mechanical parameters when designing pavement structures based on the dual modulus theory, so that the selection of mechanical parameters can be reasonably matched.

[0041] In this embodiment, the mechanical response analysis specifically includes analyzing the horizontal tensile strain at the bottom of the asphalt mixture layer along the driving direction, the horizontal tensile stress at the bottom of the inorganic binder stabilized layer along the driving direction, the vertical compressive stress on the top surface of each layer of the asphalt mixture, and the vertical compressive strain on the top surface of the subgrade. The maximum mechanical response value of the corresponding mechanical response calculation point is taken according to the pavement structure. The smaller the maximum mechanical response value of different pavement structures, the better the mechanical performance of the pavement structure. Finally, the combination corresponding to the smallest maximum mechanical response value is selected as the optimal pavement structure material mix ratio combination.

[0042] Further mechanical response analysis also includes corrections using the following formula:

[0043] in, , These are the uniaxial compressive modulus and the direct tensile modulus, respectively. , These are the uniaxial compression Poisson's ratio and the direct tension Poisson's ratio, respectively.

[0044] The fundamental assumptions of bimodulus theory include the compliance symmetry assumption, which requires... In this embodiment, when performing calculations based on the dual-modulus theory, it is necessary to further modify the mechanical parameters to satisfy the assumptions, so that the modified mechanical parameters are as close as possible to the experimental data.

[0045] This invention is based on the integrated design concept of materials and structures. It utilizes the tensile and compressive modulus differences and value matching of mechanical parameters to achieve optimized design of asphalt pavement. It considers the influence of cement dosage and asphalt content on the mechanical parameters of pavement materials. By acquiring the material mechanical parameters, a correlation model is established between the mechanical parameters and changes in cement dosage and asphalt content. Then, mechanical response analysis is performed on the mechanical parameters under different cement dosage and asphalt content mix ratios. By adjusting the mix ratio of pavement materials, the mechanical response of different pavement structures is calculated. Based on the analysis results, the optimal mix ratio combination is determined, maximizing the mechanical performance of the pavement structure. This invention fully considers the differences in tensile and compressive moduli, reflecting the true mechanical response of the pavement. Simultaneously, it provides an accurate quantitative range for the selection of mechanical parameters when designing pavement structures based on the dual-modulus theory, ensuring that the selected material parameters match the true mechanical properties of the materials. This effectively improves the rationality of pavement structure design, thereby extending the service life of the pavement and preventing severe structural damage within its service life.

[0046] The following example, using the above method to achieve optimized design of asphalt pavement structure in a specific application embodiment, further illustrates the present invention. The detailed steps are as follows: Step 1) Configure the initial road surface structure.

[0047] According to the requirements of the "Specifications for Design of Asphalt Pavement of Highways" (JTG D50-2017) and actual needs, the design traffic load level is 50×10. 8 The experiment used PC 32.5 cement, SBS(ID) modified asphalt, and limestone as the test aggregate and mineral powder. The pavement structure was initially configured using a suspended dense gradation type and an AC-16 dense gradation type mix design for cement-stabilized crushed stone and asphalt mixtures. The gradation curves are shown below. Figure 2 and Figure 3 As shown in Table 1, the specific road surface structure configuration is as follows.

[0048] Table 1: Initial pavement structure configuration

[0049] The selected ranges for the cement dosage of cement-stabilized crushed stone were 1%, 2%, 3%, 4%, and 5%, and the ranges for the asphalt dosage of asphalt mixture were 3.5%, 4%, 4.5%, 5%, and 5.5%, respectively. The values ​​for temperature and loading rate were 20℃ and 0.1MPa / s, respectively.

[0050] Step 2) Establish a correlation model between the mechanical parameters of cement-stabilized crushed stone and asphalt mixture and the cement dosage and asphalt content.

[0051] Modulus and Poisson's ratio tests were conducted under compression and tensile stress states to establish models relating cement-stabilized crushed stone to cement dosage and asphalt mixtures to asphalt content. Specifically: Correlation model for cement-stabilized crushed stone:

[0052]

[0053]

[0054]

[0055] Correlation model for asphalt mixtures:

[0056]

[0057]

[0058]

[0059] Step 3) Combine the road surface materials according to their proportions and determine the corresponding mechanical parameters.

[0060] Based on the selected cement dosage and asphalt content ranges for the pavement structure (cement dosages of 3.5%, 4%, and 4.5%, and asphalt content of 4.5%, 5%, and 5.5%), parameters were calculated using a correlation model. Each cement dosage and asphalt content was combined once, resulting in nine possible combinations. The parameters for the granular layer and subgrade were selected according to the standard "Specification for Design of Highway Asphalt Pavement" (JTG D50-2017). Specific mechanical parameter values ​​are shown in Table 2.

[0061] Table 2: Values ​​of Mechanical Parameters

[0062] Step 4) Determine the optimal mix proportion combination for the pavement structure. Nine combinations were tested using finite element analysis software for pavement structure design and calculation based on bimodulus theory. The pavement structure's base is an inorganic binder, and the subbase is granular. Table 3 compares the horizontal tensile stress along the driving direction at the bottom of the inorganic binder stabilized layer and the vertical compressive stress at the top surface of the asphalt mixture layer. The vertical compressive stress at the top surface of the asphalt mixture layer is not significantly different. It can be seen that when the asphalt content of the asphalt mixture is 5.0%, the vertical compressive stress at the top surface of the asphalt mixture layer is smaller, the modulus of the surface layer is the largest, and the deformation is relatively small. Therefore, an asphalt mixture with 5.0% asphalt content is selected as the surface layer. The horizontal tensile stress along the driving direction at the bottom of cement-stabilized crushed stone layers with cement dosages of 3.5%, 4%, and 4.5% is substituted into the fatigue cracking formula for inorganic binder stabilized layers in the "Specifications for Design of Highway Asphalt Pavement" (JTG D50-2017) for calculation. The flexural tensile strengths obtained through experiments are 1.4 MPa, 1.58 MPa, and 1.68 MPa, respectively. Other parameters are selected according to the specifications. The calculated fatigue life is 75.76 × 10⁻⁶. 8 83.51×10 8 and 79.40×10 8 The results showed that the cement-stabilized crushed stone base course had the longest fatigue cracking life when the cement dosage was 4%. Therefore, the final mix proportion was selected as 5.0% asphalt and 4% cement.

[0063] Table 3: Combination Methods

[0064] Considering both economic benefits and optimizing the mechanical response, the base course thickness was changed to 32cm and 34cm respectively, and the mechanical response was calculated, as shown in Table 4. The results show that the vertical compressive stress on the top surface of the asphalt mixture layer is the same for all three thicknesses. Meanwhile, as the thickness decreases, the horizontal tensile stress along the driving direction at the bottom of the inorganic binder stabilized layer increases. The fatigue life of the cement-stabilized crushed stone base course was calculated; when the thickness is 32cm, the fatigue life is 46.91 × 10⁻⁶. 8 When the thickness is 34cm, the fatigue life is 80.49×10⁻⁶. 8 The fatigue life is reduced. From the perspective of economic benefits, a thickness of 34cm is selected. Therefore, the final pavement structure is shown in Table 5.

[0065] Table 4: Mechanical Response After Different Substrate Thicknesses

[0066] Table 5: Finalized pavement structure

[0067] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Therefore, any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention should fall within the protection scope of the present invention.

Claims

1. A method for optimizing the design of asphalt pavement structures based on mechanical parameter analysis, characterized in that, The steps include: S01. Configure the initial pavement structure and the range of values ​​for cement dosage of cement stabilized crushed stone and asphalt content of asphalt mixture. S02. Establish a correlation model between the mechanical parameters of cement-stabilized crushed stone and asphalt mixture and the cement dosage and asphalt content. The correlation model includes a correlation model between the mechanical parameters of cement-stabilized crushed stone and the cement dosage, and a correlation model between the mechanical parameters of asphalt mixture and the asphalt content. The mechanical parameters include tensile and compressive modulus and tensile and compressive Poisson's ratio. The tensile and compressive modulus includes compression modulus and tensile modulus. The tensile and compressive Poisson's ratio includes compression Poisson's ratio and tensile Poisson's ratio. S03. Within the configured range of values, determine a variety of different pavement structure material mix proportions, and under different pavement structure material mix proportions, determine the corresponding mechanical parameters according to the correlation model. The pavement structure material mix proportions are mix proportions formed by different asphalt dosages and different cement dosages. S04. Perform mechanical response analysis on the mechanical parameters obtained under each combination of pavement structure materials mix proportions, and determine the optimal combination of pavement structure materials mix proportions based on the mechanical response analysis.

2. The asphalt pavement structure optimization design method based on mechanical parameter analysis according to claim 1, characterized in that, The initial pavement structure configuration in step S01 includes configuring the cement-stabilized crushed stone base asphalt pavement structure type, structural layer thickness, and the material type and gradation of each component in the cement-stabilized crushed stone and asphalt mixture in the pavement structure layer.

3. The asphalt pavement structure optimization design method based on mechanical parameter analysis according to claim 2, characterized in that, The configuration value range also includes the value ranges for temperature and loading rate.

4. The asphalt pavement structure optimization design method based on mechanical parameter analysis according to claim 1, characterized in that, In step S02, the tensile modulus and tensile Poisson's ratio under compressive and tensile stress states are determined by modulus and Poisson's ratio tests, respectively, with the variation of asphalt content and cement content. The variation relationship is then fitted and regressed to establish a functional relationship model, resulting in correlation models between the tensile modulus and cement content of cement-stabilized crushed stone, and between the tensile Poisson's ratio and cement content, as well as correlation models between the tensile modulus and asphalt content of asphalt mixtures, and between the tensile Poisson's ratio and asphalt content.

5. The asphalt pavement structure optimization design method based on mechanical parameter analysis according to claim 4, characterized in that, The correlation model between the tensile and compressive modulus and Poisson's ratio of the cement-stabilized crushed stone and the cement dosage is as follows: in, M For cement dosage, , , These are the fitting parameters; in, , , These are the fitting parameters; The correlation model between the tensile and compressive modulus and Poisson's ratio of the asphalt mixture and the asphalt content is as follows: in, This refers to the amount of asphalt used. , , These are the fitting parameters; in, , , These are the fitting parameters.

6. The asphalt pavement structure optimization design method based on mechanical parameter analysis according to claim 4, characterized in that, The determination of the relationship between the compressive and tensile moduli and Poisson's ratio as a function of asphalt content and cement dosage through modulus and Poisson's ratio tests under compressive and tensile stress states includes: before the test, fixing the extensometer to the pre-marked scale positions on both sides of the specimen and then placing it on the MTS testing system; selecting the stress control mode; performing multi-stage loading and unloading on the asphalt mixture and cement-stabilized crushed stone respectively; the magnitude of each load stage is a specified proportion of the maximum destructive load; pausing for a specified time after unloading each load stage before the next loading is performed; and recording the strain magnitude during the loading and unloading process; and calculating the uniaxial compressive and direct tensile moduli based on the test results.

7. The asphalt pavement structure optimization design method based on mechanical parameter analysis according to claim 6, characterized in that, The uniaxial compressive-tensile Poisson's ratio and the direct tensile Poisson's ratio are calculated using the ratio of vertical strain to transverse strain at 0.5 μm. The calculation expression is as follows: in, It is the uniaxial compressive modulus. For direct tensile modulus, For each stage of compressive and tensile load during uniaxial compression, For each stage of compressive and tensile load during direct tension, This represents the vertical springback strain under uniaxial compression. This represents the vertical springback strain during direct tension. For uniaxial compression or direct tension vertical springback strain, For uniaxial compression or direct tension, the lateral springback strain is... For uniaxial compression or direct stretching, Poisson's ratio, b The width of the direct tensile test specimen for asphalt mixture. h To directly stretch the height of the specimen, d The diameter is the diameter of the uniaxial compression specimen of the asphalt mixture.

8. The asphalt pavement structure optimization design method based on mechanical parameter analysis according to any one of claims 1 to 7, characterized in that, In step S04, the mechanical response analysis is performed using a road structure design and finite element analysis method based on bimodulus theory.

9. The asphalt pavement structure optimization design method based on mechanical parameter analysis according to any one of claims 1 to 7, characterized in that, In step S04, the mechanical response analysis includes analyzing the horizontal tensile strain at the bottom of the asphalt mixture layer along the driving direction, the horizontal tensile stress at the bottom of the inorganic binder stabilized layer along the driving direction, the vertical compressive stress on the top surface of each layer of the asphalt mixture layer, and the vertical compressive strain on the top surface of the subgrade. Based on the pavement structure, the maximum mechanical response value of the corresponding category mechanical response calculation point is taken, and the combination corresponding to the minimum maximum mechanical response value is selected as the optimal pavement structure material mix ratio combination.

10. The asphalt pavement structure optimization design method based on mechanical parameter analysis according to any one of claims 1 to 7, characterized in that, When performing mechanical response analysis in step S04, the following correction formula is also included: in, , These are the uniaxial compressive modulus and the direct tensile modulus, respectively. , These are the uniaxial compression Poisson's ratio and the direct tension Poisson's ratio, respectively.

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