CN-121997650-A - Mechanical property evaluation method for simulating asphalt mixture based on discrete element values

CN121997650ACN 121997650 ACN121997650 ACN 121997650ACN-121997650-A

Abstract

The invention provides a mechanical property evaluation method for simulating asphalt mixture based on discrete element values, which relates to the technical field of road materials and comprises the steps of setting unit radius and boundary unit radius of component particles of the asphalt mixture to be tested, adjusting distribution of the component particle sizes and a contact model among different component particles, establishing an initial discrete element model, carrying out a semicircular bending test based on the initial discrete element model to obtain a microscopic mechanical property parameter of the asphalt mixture to be tested, determining a damage dimension parameter by an ideal solution sorting method, respectively corresponding sub-index matrixes of force transfer dimension parameters and structure dimension parameters, weighting all the sub-index matrixes by combining an objective weighting method, and obtaining a comprehensive evaluation index, and determining the microscopic mechanical property of the asphalt mixture to be tested based on the comprehensive evaluation index, wherein the sub-index matrix comprises a damage sub-index, a force transfer sub-index and a structure sub-index.

Inventors

HUANG XIAOYAN
ZHANG YUCHEN
WANG LAN
BAN YINGYING
Xiong Meiyan
WANG CHONG

Assignees

内蒙古工业大学

Dates

Publication Date: 20260508
Application Date: 20260119

Claims (10)

1. The mechanical property evaluation method for simulating the asphalt mixture based on discrete element values is characterized by comprising the following steps of: Setting unit radius and boundary unit radius of component particles of the asphalt mixture to be tested, adjusting distribution of component particle sizes and a contact model among different component particles, and establishing an initial discrete element model; performing a semicircle bend test based on the initial discrete element model to obtain the mesomechanics characteristic parameters of the asphalt mixture to be tested, wherein the mesomechanics characteristic parameters comprise damage dimension parameters, force transmission dimension parameters and structure dimension parameters; Determining the damage dimension parameters by using an ideal solution ordering method, respectively corresponding sub-index matrixes of the force transfer dimension parameters and the structure dimension parameters, weighting each sub-index matrix by combining an objective weighting method to obtain a comprehensive evaluation index, and determining the microscopic mechanical property of the asphalt mixture to be tested based on the comprehensive evaluation index, wherein each sub-index matrix comprises a damage sub-index, a force transfer sub-index and a structure sub-index.
2. The method for evaluating mechanical properties of a simulated asphalt mixture based on discrete element values according to claim 1, wherein the component particles comprise aggregate particles and asphalt cement particles, wherein the step of setting unit radius and boundary unit radius of the component particles of the asphalt mixture to be tested, adjusting distribution of component particle size and a contact model between different component particles, and establishing an initial discrete element model comprises the steps of: The method comprises the steps of randomly generating aggregate particles and asphalt cement particles in a preset semicircular test piece space according to grading requirements, wherein the aggregate particles are represented by irregular polygonal particle clusters, the asphalt cement particles are represented by spheres with uniform particle sizes, a contact model between the aggregate particles is a contact stiffness model, and a contact model between the aggregate particles and the asphalt cement particles is a parallel bonding model.
3. The method for evaluating mechanical properties of a discrete element numerical simulation asphalt mixture according to claim 1, wherein the damage dimension parameters comprise bond failure proportion, breaking energy accumulation and breaking energy, the force transmission dimension parameters comprise force chain variation coefficient, average force chain length and high force contact tail ratio, and the structure dimension parameters comprise contact anisotropy coefficient, strong chain average length and strong contact ratio.
4. The method for evaluating mechanical properties of a simulated asphalt mixture based on discrete element values according to claim 3, wherein the step of performing a semicircular bending test based on the initial discrete element model to obtain the microscopic mechanical property parameters of the asphalt mixture to be tested comprises the steps of: Determining a bonding failure proportion based on the ratio of the number of bonds subjected to failure to the total number of bonds, summing the energy released by the plurality of bonding failures to determine fracture energy accumulation, and integrating based on loading counter force and loading displacement to obtain fracture energy; Determining a force chain variation coefficient based on a standard deviation of force chain strength and average strength of the force chain, averaging the length sum of all force chains to obtain average force chain length, and determining a high-force contact tail ratio based on the proportion of the contact number greater than a high-force threshold value in all contact numbers; And calculating a contact anisotropy coefficient based on the contact texture tensor principal value, carrying out averaging on the length sum of all the strong chains to obtain the average length of the strong chains, and determining the strong contact duty ratio based on the proportion of the number of strong contacts in all the number of contacts.
5. The method for evaluating mechanical properties of a simulated asphalt mixture based on discrete element values according to claim 1, wherein determining the damage dimension parameter by using an ideal solution ordering method, the sub-index matrix corresponding to the force transmission dimension parameter and the structure dimension parameter respectively comprises: Acquiring an original parameter matrix of each parameter in the mesomechanics characteristic parameters, and carrying out standardization processing on the original parameter matrix to obtain a corresponding standardization matrix; Determining the distance between each parameter in the standardized matrix and the positive ideal solution and the distance between each parameter in the standardized matrix and the negative ideal solution based on the positive ideal value and the negative ideal value corresponding to the standardized matrix to obtain a positive distance matrix and a negative distance matrix; and calculating a sub-index matrix of each parameter in the mesomechanics characteristic parameters based on the positive distance matrix and the negative distance matrix.
6. The method for evaluating mechanical properties of a discrete element numerical simulation asphalt mixture according to claim 5, wherein determining a distance between each parameter in the standardized matrix and a positive ideal solution and a distance between each parameter in the standardized matrix and a negative ideal solution based on the positive ideal value and the negative ideal value corresponding to the standardized matrix to obtain a positive distance matrix and a negative distance matrix comprises: And calculating the distance between each parameter in the standardized matrix and the positive ideal solution and the distance between each parameter in the standardized matrix and the negative ideal solution by using Euclidean distance to obtain a positive distance matrix and a negative distance matrix.
7. The evaluation method for mechanical properties of a discrete element numerical simulation asphalt mixture according to claim 1, wherein the step of weighting each sub-index matrix by combining an objective weighting method, and obtaining a comprehensive evaluation index through weighted fusion comprises the steps of: Obtaining standard deviation of all sub-indexes in each column of the sub-index matrix to obtain a standard deviation vector, and calculating a correlation coefficient between any two sub-indexes in the sub-index matrix to obtain a correlation coefficient matrix; determining a comparison intensity value of each sub-index based on the standard deviation vector and the correlation coefficient matrix; normalizing the comparison intensity value to obtain the weight corresponding to each sub-index, and carrying out weighted fusion on each sub-index matrix based on the weight to obtain the comprehensive evaluation index.
8. A mechanical property evaluation system for simulating asphalt mixture based on discrete element values is characterized by comprising a model creation module, a parameter acquisition module and a weighted fusion module, wherein, The model creation module is configured to set the unit radius and the boundary unit radius of component particles of the asphalt mixture to be tested, adjust the distribution of the particle sizes of the component particles and the contact model among different component particles, and build an initial discrete element model; the parameter acquisition module is configured to perform a semicircular bending test based on the initial discrete element model to acquire the mesomechanics characteristic parameters of the asphalt mixture to be tested, wherein the mesomechanics characteristic parameters comprise damage dimension parameters, force transmission dimension parameters and structure dimension parameters; the weighted fusion module is configured to determine the damage dimension parameters by using an ideal solution ordering method, the sub-index matrixes corresponding to the force transmission dimension parameters and the structure dimension parameters respectively, and weight each sub-index matrix by combining an objective weighting method, so as to obtain a comprehensive evaluation index through weighted fusion, and determine the microscopic mechanical property of the asphalt mixture to be tested based on the comprehensive evaluation index, wherein each sub-index matrix comprises a damage sub-index, a force transmission sub-index and a structure sub-index.
9. An electronic device comprising a processor and a memory, the memory storing a computer program, wherein the computer program when executed by the processor implements the method for evaluating mechanical properties of a simulated asphalt mixture based on discrete element values of any one of claims 1 to 7.
10. A non-transitory computer-readable storage medium, having stored thereon a computer program, wherein the computer program, when executed by a processor, implements the method for evaluating mechanical properties of a simulated asphalt mixture based on discrete element values as claimed in any one of claims 1 to 7.

Description

Mechanical property evaluation method for simulating asphalt mixture based on discrete element values Technical Field The invention relates to the technical field of road materials, in particular to a mechanical property evaluation method for simulating an asphalt mixture based on discrete element values. Background The mechanical properties of the asphalt mixture, which is used as the most critical pavement material in road engineering, directly determine the use quality, durability and safety of the road. In the road operation process, the asphalt mixture needs to bear the repeated action of vehicle load, expansion and contraction caused by temperature change and the comprehensive influence of natural environment factors such as rain erosion, ultraviolet irradiation and the like. The good mechanical property can ensure that the asphalt pavement keeps smooth and anti-skid in the long-term use process, and effectively resists the generation and development of ruts, cracks and other diseases, thereby reducing the maintenance cost of the road, prolonging the service life of the road and ensuring the smoothness and safety of traffic and transportation. The mechanical properties of the asphalt mixture are closely related to the internal particle structure, the force chain distribution and the bonding characteristics. The traditional evaluation method of the mechanical properties of the asphalt mixture is mainly based on macroscopic mechanical indexes such as compressive strength, low-temperature bending strength, splitting strength, dynamic stability and the like. The macro indexes are obtained through laboratory standard tests, the operation is relatively simple and convenient, and the integral bearing capacity and the deformation resistance of the asphalt mixture under different stress conditions can be reflected to a certain extent. However, these macroscopic evaluation methods have significant limitations. The method can only roughly judge the mechanical properties of the mixture on the whole, and cannot deeply disclose the microscopic evolution mechanism of the internal structure of the mixture. In practical engineering, the destruction of asphalt mixtures often does not originate from uniform failure of the whole material, but rather is initiated by progressive expansion of the damage to the internal local structure. The macroscopic index is difficult to capture the gradual process from the damage of the microscopic structure to the macroscopic damage, and key microscopic information such as the contact behavior between particles, the force chain bearing efficiency, the crack propagation path and the like cannot be accurately quantified. In addition, the mechanical properties of the asphalt mixture are the combined effect of a plurality of microscopic factors, and the single index often has difficulty in comprehensively and accurately reflecting the actual mechanical state of the mixture. Because the mechanical properties of the asphalt mixture cannot be accurately obtained, the operation and maintenance of the pavement are difficult to accurately control, and therefore the service life, maintenance cost and safety of the pavement are affected. Disclosure of Invention In view of the above, the invention provides a mechanical property evaluation method for simulating asphalt mixture based on discrete element values. The technical scheme of the invention is realized in such a way that the first aspect of the invention provides a mechanical property evaluation method for simulating asphalt mixture based on discrete element values, which comprises the following steps: Setting unit radius and boundary unit radius of component particles of the asphalt mixture to be tested, adjusting distribution of component particle sizes and a contact model among different component particles, and establishing an initial discrete element model; performing a semicircle bend test based on the initial discrete element model to obtain the mesomechanics characteristic parameters of the asphalt mixture to be tested, wherein the mesomechanics characteristic parameters comprise damage dimension parameters, force transmission dimension parameters and structure dimension parameters; Determining the damage dimension parameters by using an ideal solution ordering method, respectively corresponding sub-index matrixes of the force transfer dimension parameters and the structure dimension parameters, weighting each sub-index matrix by combining an objective weighting method to obtain a comprehensive evaluation index, and determining the microscopic mechanical property of the asphalt mixture to be tested based on the comprehensive evaluation index, wherein each sub-index matrix comprises a damage sub-index, a force transfer sub-index and a structure sub-index. On the basis of the technical scheme, the component particles preferably comprise aggregate particles and asphalt cement particles, the unit radius and the boundary unit radius of the