Preparation method of aged asphalt for on-site heat regeneration tests

Abstract

The invention discloses a preparation method of aged asphalt for on-site heat regeneration tests, belonging to the field of a preparation method of asphalt mixed materials. The method comprises the following steps: firstly, collecting road surface mixture after construction heating from an asphalt road section to be constructed, extracting and recovering to obtain an asphalt binder, and carrying out an index test on the asphalt binder; then, carrying out a rolling thin-film oven ageing test on original sample substrate asphalt with the same label, blowing hot air into an oven at the flow rate of 4000ml / min under the conditions that the temperature is 163 DEG C and the rotation speed is 15r / min, and baking each group of asphalt samples for different time; carrying out the index test again, drawing a corresponding index curve according to the test result, and carrying out function fitting; comparing the fitting result with the firstly tested index value to determine a reference index, and then, computing the ageing time according to the reference; and finally, preparing the aged asphalt for the on-site heat regeneration tests by using the thin-film oven ageing method according to the ageing time. The method of the invention has the advantages of large yield, low cost, simple operation, high simulation degree of products, and the like.

Description

technical field [0001] The invention relates to a preparation method of asphalt mixture, in particular to a preparation method of aged asphalt. Background technique [0002] With the development of our country's economy and society, our country's highway transportation has also developed rapidly. By the end of 2009, the total mileage of national roads opened to traffic reached 3,828,200 kilometers; among them, 75,000 kilometers were highways. With the continuous increase of road mileage, road grades are also continuously improved, a large number of low-grade roads have been rebuilt and expanded, and road traffic is playing an increasingly important role in national economic life. [0003] The vast majority of high-grade highways in my country's highways are asphalt pavements. During the course of use, the asphalt pavement will gradually harden and age under the action of traffic load and natural factors. Compared with the original asphalt, the aging asphalt has lower pene...

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Problems solved by technology

[0010] 3) Film oven aging method: The film oven aging method is one of the commonly used asphalt aging methods at present. According to different research purposes, it can be divided into two film oven aging methods with a film thickness of 20 μm and 3 mm; in 1973, Schmidt proposed asphalt rotation Thin film aging method (RTFOT), its advantage is that each part of the sample can be aged under the same conditions, but due to the small amount of sample, the property detection cannot be completed; in 1989, Petersen proposed the thin film accelerated aging method (TFAAT), its main improvement The sample size was increased from 0.5g to 4.0g; in 1993, the Federal Highway Administration of the United States proposed a 1mm-3mm surface renewal film oven aging method;

[0012] However, none of the existing indoor simulation aging methods can truly simulate the construction conditions and construction environment of on-site thermal regeneration technology, and the prepared aged asphalt cannot truly reflect the pavement asphalt under the construction state of on-site thermal regeneration, which will definitely affect The experimental effect of the on-site thermal regeneration experiment will affect the use effect of the asphalt rejuvenator prepared based on the experimental data, and finally affect the quality and effectiveness of the on-site thermal regeneration asphalt

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