CN-122013634-A - Andesite asphalt mixture and preparation method thereof

CN122013634ACN 122013634 ACN122013634 ACN 122013634ACN-122013634-A

Abstract

The invention relates to the technical field of road building materials, in particular to an andesite asphalt mixture and a preparation method thereof, wherein the andesite asphalt mixture comprises the steps of adding heated andesite coarse aggregate, limestone machine-made sand and mineral filler into a stirrer for dry stirring; the method comprises the steps of adding heated asphalt and a surface modifier for wet mixing, judging that the andesite asphalt mixture is in a critical coating state according to a coating uniformity characterization value in the wet mixing process, increasing the preset stirring speed of the stirrer to respond to the critical coating state, correcting the preset stirring speed when the sharp contour characterization value of the andesite asphalt mixture is larger than or equal to the preset sharp contour characterization value after the preset stirring speed is increased, and determining the preparation adjustment strategy of the andesite asphalt mixture according to the temperature drop speed of the andesite asphalt mixture when the andesite asphalt mixture is in a coating non-uniformity state according to the coating uniformity characterization value. The invention improves the preparation efficiency of the andesite asphalt mixture.

Inventors

WEI YUMIN
LIU ZHIHENG
CHEN CHANGYU
GAO XUEGUANG
YUAN JIE
GAO SHUAI
XU KEPENG
GAO PENG
GUO CHEN
LU KAIQIANG
FANG YEHUI
GAO ZHUANGZHUANG

Assignees

中铁北京工程局集团第六工程有限公司
中铁北京工程局集团有限公司

Dates

Publication Date: 20260512
Application Date: 20260410

Claims (10)

1. The preparation method of the andesite asphalt mixture is characterized by comprising the following steps of: Adding heated asphalt, and adding a surface modifier to perform wet mixing at a preset stirring time and a preset stirring rate; in the wet mixing process, acquiring a surface image of the andesite asphalt mixture, and obtaining a uniformly-coated characterization value of the andesite asphalt mixture; Judging that the andesite asphalt mixture is in a critical coating state according to the coating uniformity characterization value, and increasing the preset stirring rate of the stirrer according to the difference value between the coating uniformity characterization value and a first preset coating uniformity characterization value so as to respond to the critical coating state; After increasing the preset stirring rate of the stirrer, correcting the preset stirring rate when the sharp outline characterization value of the andesite asphalt mixture is greater than or equal to the preset sharp outline characterization value; determining a preparation adjustment strategy of the andesite asphalt mixture according to the temperature drop rate of the andesite asphalt mixture when the andesite asphalt mixture is in a non-uniformly-coated state according to the uniformly-coated representation value, wherein the preparation adjustment strategy is to spray atomized water with a preset dosage into a stirrer or pause wet mixing and trigger asphalt replenishment alarm; And discharging the andesite asphalt mixture meeting the preset standard.
2. The method for preparing the andesite asphalt mixture according to claim 1, wherein the andesite coarse aggregate is heated to 180-190 ℃ to obtain heated andesite coarse aggregate, the limestone machine-made sand is heated to 170-185 ℃ to obtain heated limestone machine-made sand, and the asphalt is heated to 150-170 ℃ to obtain heated asphalt.
3. The method for preparing the andesite asphalt mixture according to claim 1, wherein when the andesite asphalt mixture is in a critical coating state according to a comparison result that the uniform coating characterization value of the andesite asphalt mixture is larger than or equal to a first preset uniform coating characterization value and smaller than a second preset uniform coating characterization value, the preset stirring rate of the stirrer is increased according to a difference value between the uniform coating characterization value and the first preset uniform coating characterization value, wherein the first preset uniform coating characterization value is smaller than the second preset uniform coating characterization value.
4. A method of preparing an andesite asphalt mixture as defined in claim 3, wherein the process of obtaining the uniformly coated characterizing value of the andesite asphalt mixture comprises: carrying out graying treatment on the acquired surface image to obtain a gray image of the andesite asphalt mixture; calculating standard deviation of gray values of all pixel points in the gray image; and taking the standard deviation as a coating uniformity characterization value of the andesite asphalt mixture.
5. The method for preparing an andesite asphalt mixture according to claim 4, wherein when the andesite asphalt mixture is determined to be in a non-uniformly coated state according to a comparison result that the uniformly coated representation value of the andesite asphalt mixture is greater than or equal to the second preset uniformly coated representation value, a preparation adjustment strategy of the andesite asphalt mixture is determined according to a temperature drop rate of the andesite asphalt mixture.
6. The method of claim 4, wherein the step of determining whether the andesite asphalt mixture is prepared to meet a predetermined criterion based on the sharp profile characterizing value of the andesite asphalt mixture after increasing the predetermined stirring rate comprises: If the sharp outline characterization value is smaller than a preset sharp outline characterization value, judging that the preparation of the andesite asphalt mixture meets a preset standard; If the sharp characterization value of the contour is larger than or equal to the preset sharp characterization value of the contour, judging that the preparation of the andesite asphalt mixture does not meet a preset standard, and correcting the preset stirring rate according to the difference value between the sharp characterization value of the contour and the sharp characterization value of the preset contour; The sharp profile characterizing value of the andesite asphalt mixture is determined by the interior angles of the profiles of the plurality of particles of the andesite asphalt mixture of the gray scale image.
7. The method of claim 6, wherein a plurality of rate modification modes are provided for modification of the preset stirring rate, and the modification amplitude of each rate modification mode for the preset stirring rate is different.
8. The method of preparing an andesite asphalt mixture according to claim 5, wherein the process of determining a preparation adjustment strategy for the andesite asphalt mixture according to a temperature drop rate of the andesite asphalt mixture comprises: If the temperature drop rate is smaller than the preset temperature drop rate, spraying atomized water with a preset dosage into the stirrer; If the temperature drop rate is greater than or equal to the preset temperature drop rate, suspending wet mixing and triggering an asphalt replenishment alarm.
9. The method for preparing an andesite asphalt mixture according to claim 8, wherein the process of obtaining the temperature drop rate of the andesite asphalt mixture comprises: acquiring the temperature of the andesite asphalt mixture at the beginning of wet mixing, and recording the temperature as a first temperature; acquiring the temperature of the andesite asphalt mixture after wet mixing for a preset stirring time period, and recording the temperature as a second temperature; Calculating the difference between the first temperature and the second temperature, and recording the difference as a temperature difference; and recording the ratio of the temperature difference value to the preset stirring time as the temperature drop rate of the andesite asphalt mixture.
10. The andesite asphalt mixture prepared by the preparation method according to any one of claims 1-9 is characterized by comprising, by mass, 56% -77% of andesite coarse aggregate, 11% -27% of limestone machine-made sand, 2% -4% of mineral filler, 4.5% -4.6% of asphalt and a surface modifier accounting for 0.4% of asphalt, wherein the andesite coarse aggregate comprises hot bunker gravels with the particle sizes of 16-22mm, 11-16mm, 6-11mm and 3-6mm respectively, the mass ratio of each of the gravels with the particle sizes of 18% -30%, 16% -23%, 12% -20% and 6% -8%, the limestone machine-made sand comprises a hot bunker machine with the particle size of 0-3mm, and the mineral filler comprises mineral powder and cement according to the mass ratio of 1:1.

Description

Andesite asphalt mixture and preparation method thereof Technical Field The invention relates to the technical field of road building materials, in particular to an andesite asphalt mixture and a preparation method thereof. Background Asphalt mixture is used as the most main paving material in modern road engineering, and the performance and cost of the asphalt mixture are directly related to the construction quality, service life and economic benefit of the road. In engineering construction, especially in mountainous areas, hills and other multi-tunnel areas, the projects are often distributed with abundant neutral rock resources such as andesite along the lines, or a large amount of tunnel hole slag is generated. If the materials can be obtained locally, the resources are processed into asphalt mixture aggregates, the remote transportation cost of raw materials can be greatly reduced, the intensive utilization of the resources is realized, and the sustainable development concept of green and economy is met. However, andesite, as a typical aluminous neutral rock, has surface chemistry that is slightly acidic and generally poor in adhesion to commonly used asphalt. Under the condition of water erosion, asphalt films of the mixture are easy to peel off, so that early diseases such as water damage, loosening and the like of the pavement are caused, and the safe application of the mixture in asphalt pavement, especially in the pavement structure of high-grade highways, is severely restricted. In order to improve the adhesiveness, a method of adding an anti-stripping agent (such as various amines, lime and the like) is generally adopted in the industry, but the effect stability and the accurate control of the blending amount still remain difficulties in practical engineering. On the other hand, the production quality of asphalt mixture is highly dependent on the stability of the mixing process, and real-time diagnosis and dynamic adjustment of the production process cannot be realized, which may result in unstable batch quality or generation of unqualified materials. Chinese patent application publication No. CN117142785A discloses a method for preparing recycled aggregate concrete of andesite, 1) crushing waste concrete with a jaw crusher and removing impurities therein, 2) passing the crushed waste concrete obtained in step 1) through a magnetic separator to remove iron scraps contained in original waste concrete, 3) sieving the waste concrete obtained in step 2) through a sieving machine and repeating step 1) for crushing again the waste concrete with larger particle size, 4) pouring the sieved waste concrete into water and stirring, removing impurities floating on water surface, then taking out the waste concrete and drying, 5) modifying the waste concrete obtained in step 4), and 6) grinding the modified waste concrete obtained in step 5) to obtain the finished recycled aggregate. It can be seen that the above technical scheme does not consider differential heating temperature regulation and control for andesite coarse aggregate and asphalt, does not adopt step-by-step mixing and does not consider asphalt coating state in the mixing process, so that andesite and asphalt are difficult to form uniform coating, fluctuation of mixture performance occurs, and the problem of poor preparation efficiency of andesite asphalt mixture is caused. Disclosure of Invention Therefore, the invention provides an andesite asphalt mixture and a preparation method thereof, which are used for solving the problems that the prior art does not consider differential heating temperature regulation and control of andesite coarse aggregate and asphalt, does not adopt step mixing and does not consider asphalt coating state in the mixing process, so that andesite and asphalt are difficult to uniformly coat, the performance of the mixture fluctuates, and the preparation efficiency of the andesite asphalt mixture is poor. In order to achieve the above object, in one aspect, the present invention provides a method for preparing an andesite asphalt mixture, comprising: Adding heated asphalt, and adding a surface modifier to perform wet mixing at a preset stirring time and a preset stirring rate; Judging that the andesite asphalt mixture is in a critical coating state according to the coating uniformity characterization value, and increasing the preset stirring rate of the stirrer according to the difference value between the coating uniformity characterization value and a first preset coating uniformity characterization value so as to respond to the critical coating state; After increasing the preset stirring rate of the stirrer, correcting the preset stirring rate when the sharp outline characterization value of the andesite asphalt mixture is greater than or equal to the preset sharp outline characterization value; determining a preparation adjustment strategy of the andesite asphalt mixture according to the temperature drop rate of the a