Grading optimization method for asphalt mixture under virtual state

Abstract

The invention discloses a grading optimization method for an asphalt mixture under virtual state. The method includes the steps of: on the basis of grading that needs to optimize according to practical demand, in three-dimensional discrete element software PFC3D, randomly generating an asphalt mixture mechanical test three-dimensional discrete element model (including uniaxial penetration test, low temperature split test, uniaxial compression test and shear fatigue test) which satisfies a target grading, wherein the generation process of the three-dimensional discrete element model, which satisfies the target grading, is the base of asphalt mixture grading optimization; and comparing mechanical performance evaluation results of various grading to obtain a grading having best mechanical performance. The method has strong operability, convenience and representativeness.

Description

technical field [0001] The invention relates to an asphalt mixture gradation optimization method in a virtual state, belonging to the field of road engineering. Background technique [0002] The composition of asphalt mixture includes four parts: asphalt, aggregate, additive and void, among which aggregate has the greatest influence on the performance of asphalt mixture. The physical properties of aggregates (shape, size, edges, flatness, surface texture, etc.), gradation, and distribution in asphalt mixtures (position, quantity, spacing, azimuth, etc.) all have an impact on asphalt mixtures. It has a significant impact on the mechanical properties, road performance indicators and fatigue life. Among the many factors affecting the performance of asphalt mixture, the gradation of aggregate is the most macroscopic and fundamental. To some extent, aggregate gradation determines the performance of asphalt mixture and affects the road performance and service life of asphalt mix...

AI Technical Summary

Problems solved by technology

[0003] The traditional optimization of asphalt mixture gradation is mainly based on continuum mechanics, with the accumulation and analysis of a large amount of data from laboratory tests or test roads as the research method, but there are the following shortcomings: (1) The theory of continuum mechanics is based on uniform, continuous, anisotropic The basic assumptions of homogeneity and small deformation are not suitable for describing asphalt mixture, a material with obvious particle characteristics; (2) the indoor test workload is large, the cycle is long, the test result is not stable, and the dependence on the experimenter is high

[0010] Although the above research on asphalt mixture gradation optimization method is based on the discrete element method or numerical image processing technology to describe and evaluate, but in the research, its comprehensiveness is not strong, the consideration is not comprehensive enough, and it depends on the laboratory test method. Cannot conveniently optimize asphalt mixture gradation

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