Visual uniaxial penetrating test-based bituminous mixture homogeneity evaluation method

Abstract

The invention discloses a visual uniaxial penetrating test-based bituminous mixture homogeneity evaluation method, which comprises the following steps: carrying out indoor molding or drilling a cylindrical core sample on site, acquiring two-dimensional horizontal section images of a plurality of bituminous mixture test pieces through tomoscan of an industrial CT machine, and then preprocessing and intensifying the two-dimensional horizontal section images acquired by the CT machine to generate gray images; recognizing and segmenting the processed bituminous mixture section gray images to obtain a boundary coordinate of each aggregate and gap in the bituminous mixture section images, establishing a three-dimensional discrete element model of the bituminous mixture and carrying out a virtual uniaxial penetration test, and evaluating the bituminous mixture homogeneity by using the uniaxial penetration strength index variable coefficient obtained by the test. The bituminous mixture homogeneity evaluation method is based on the visual uniaxial penetrating test, and the bituminous mixture homogeneity is quantitatively evaluated by using the uniaxial penetration strength index variable coefficient, so the industrial practicability and maneuverability are very strong.

Description

technical field [0001] The invention relates to the technical field of road engineering, in particular to a method for evaluating the uniformity of asphalt mixture based on a virtual uniaxial penetration test. Background technique [0002] The uniformity of asphalt mixture directly determines the road performance and service life of asphalt pavement, and affects the maintenance cost of asphalt pavement. Among the many factors that potentially cause early failure of hot mix asphalt pavement, the most serious is the inhomogeneity of the asphalt mixture. Asphalt mixture is composed of asphalt, coarse and fine aggregates, additives and voids. The inhomogeneity of asphalt mixture is a comprehensive reflection of the inhomogeneity of components in asphalt mixture. The gradation of aggregates and (or) asphalt content in uneven asphalt mixtures does not match the requirements of the initial on-site mix ratio, resulting in large changes in the density and void ratio of the mixture....

AI Technical Summary

Problems solved by technology

The main reasons are as follows: (1) The influence of uniformity on the performance of asphalt mixture is ignored, and people do not give enough understanding to the importance of the uniformity of asphalt mixture

(2) The internal structure of asphalt mixture is very complex. Through traditional research methods, it is difficult to obtain the internal structure of asphalt mixture, and it is difficult to determine the uniformity of asphalt mixture.

[0006] However, the above-mentioned studies on the uniformity of asphalt mixtures, the selection and determination of the uniformity index parameters are unscientific, not comprehensive, not representative, limited to the aggregate and two-dimensional layers, the results are biased, and can only partially reflect The Reality of Uniformity

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