A Method for Asphalt Mixture Grading Prediction Based on Cold Material Monitoring

Abstract

The invention discloses a method for estimating asphalt mixture gradation through cold material monitoring, which includes: selecting a suitable camera; debugging the position of the camera and the intensity of the LED light source; determining the digital image used for analysis; converting the color image by using MATLAB It is a binary image; distance calibration of binary image; virtual screening of stone particles; estimation of aggregate particle volume; calculation of aggregate passing rate; determination of multi-grade cold material grading; bin flow rate to estimate the gradation of asphalt mixture in the mixing tank. Due to the small falling distance of the particles in the cold material bin, the method of the present invention will not cause dust problems, and the problem of uneven natural light can be overcome by adding an LED light source; the captured images are clear and continuous, and the gradation of the cold material can be accurately monitored; at the same time, On the basis of accurately monitoring the cold material gradation, combined with the flow of each cold material silo, the asphalt mixture gradation can be estimated, and can be used for asphalt mixture construction process control.

Description

Technical field [0001] The present invention is in the construction of pavement control technology, relates to a method of gradation asphalt mixture, more particularly, it relates to asphalt cold material Gradation prediction method by a monitor. Background technique [0002] Asphalt Mixture Ratio One of the main purpose of the design is given in compliance with the design requirements of the aggregate gradation. Graded Asphalt Mixture seriously affect the asphalt pavement temperature, low temperature, fatigue and water stability. Based on laboratory tests, the design asphalt mixture ratio can be designed to meet the requirements of the mineral aggregate gradation, however, the asphalt surface during the construction process, since the variability of aggregate production stall cold material inevitably gradation there will be variation, which will affect the finished asphalt mixture gradation, when the level of asphalt mixtures with variation exceeds a certain value, will reduce t...

AI Technical Summary

Problems solved by technology

In terms of road engineering, digital image processing technology has been used to measure the gradation of compacted asphalt mixture and estimate the gradation of asphalt mixture, but it belongs to the post-event asphalt mixture gradation control and cannot be used in the construction process of asphalt mixture control

In addition, existing studies have used digital image processing technology to determine the gradation of the hot silo, and then estimate the gradation of each tray of asphalt mixture. It is difficult to come; the hot material bin adopts a vibrating screen, and there is a lot of dust, which is easy to contaminate the lens, blur the lens, and the captured image is noisy, which makes it difficult to carry out digital image processing; extremely difficult

[0008] In summary, asphalt mixture gradation control is of great significance to ensure the road performance of asphalt mixture; my country's "Technical Specifications for Highway Asphalt Pavement Construction" (JTG F40-2004) stipulates that the gradation monitoring method has certain defects; due to the monitoring environment It is difficult to guarantee the accuracy and continuity of monitoring the gradation of hot silos by using digital image processing technology

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