A method for quantifying the angularity of coarse aggregate based on convex hull geometry

Abstract

The invention discloses a method for quantifying the angularity of coarse aggregate based on convex hull geometry. The method comprises an aggregate image is obtained by an aggregate edginess detection system, a series of processing such as grayscale image of aggregate is carried out, the aggregate image is read, the convex hull geometry feature is acquired, and then the convex hull image of aggregate particles is read to obtain the aggregate area before convex hull and the aggregate area after convex hull of three different surfaces of each aggregate, and the average area difference between the front and back of the convex hull is used to represent the edges and angles of a single aggregate, and the average edges and angles index is used to represent the edges and angles of a whole batchof aggregates. Therefore, the efficient and accurate detection and quantitative analysis of the angularity of aggregate are realized, and the method has the advantages of high detection efficiency, high objectivity and low detection cost.

Description

technical field [0001] The invention belongs to the field of road engineering and relates to the quantification of aggregate characteristics, in particular to a method for quantifying the angularity of coarse aggregate based on convex hull geometric features. Background technique [0002] In recent years, my country's road construction has achieved particularly remarkable results. By the end of 2017, the total mileage of the national road network had increased from 4.2375 million kilometers to more than 5 million kilometers, the mileage of expressways had increased from 96,000 kilometers to 136,000 kilometers, and 1.27 million kilometers of rural roads had been newly built and rebuilt. . Asphalt concrete pavement and cement concrete pavement are the main structural forms of highway pavement in my country, and their road performance is affected by the quality of asphalt concrete and cement concrete, while the aggregate quality accounts for 90% to 95% of the total mass of concr...

AI Technical Summary

Problems solved by technology

[0003] 1) The detection technology is backward

[0004] Since most of the existing detection methods for the angularity of aggregates use manual or semi-manual manual empirical detection, the detection equipment is huge and the mobility is poor, and the detection process is complicated, time-consuming and laborious.

[0005] 2) Poor detection accuracy

[0006] Most of the existing angular detection methods are qualitative analysis rather than quantitative analysis, the detection results are greatly affected by the level of personnel and operating habits, the accuracy of the collected data is not high and the recording process is cumbersome, and the engineering application limitations are high

[0007] 3) Different norms

[0008] The United States and Europe have their own evaluation methods for the angularity of coarse aggregates, but most of them are qualitative indicators. At present, there is no clear specification and quantitative indicators for the angularity of aggregates in my country, which varies from person to person, and is evaluated according to different standards. The angularity of aggregates varies greatly, which directly leads to confusion in the selection of asphalt mixture materials, low quality, and early road performance degradation or damage to asphalt pavement.

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