Method for testing dispersity of SBS modifier in asphalt mixture

Abstract

The invention relates to the technical field of road engineering material detection, in particular to a method for testing dispersity of an SBS modifier in an asphalt mixture. The method for testing the dispersity of the SBS modifier in the asphalt mixture comprises the following steps: (1) dispersing and sampling the asphalt mixture to be tested, dissolving a sample and filtering to obtain a solution; (2) carrying out infrared test on the solution by using a calcium fluoride or potassium bromide slide glass permeation method; (3) carrying out quantitative analysis on the obtained infrared image, carrying out integration on an infrared spectrogram, and calculating areas of two single peaks in respective characteristic peaks of the asphalt and the SBS; (4) recording the ratio of the areas of the two peaks as Z, calculating an average value, analyzing all sampling Zi values, and calculating discreteness; and when the dispersion coefficient is less than 10%, the dispersity meets the requirement. The testing method can characterize the dispersity of the SBS modifier in the asphalt mixture in multiple aspects, facilitates the dispersity evaluation of different SBS modified asphalt mixing and paving processes, and provides a basis for the improvement of a construction process.

Description

technical field [0001] The invention relates to the technical field of road engineering material detection, in particular to a method for testing the dispersibility of SBS modifier in asphalt mixture. Background technique [0002] With the development of modern transportation, traditional asphalt has gradually become difficult to meet the technical requirements of road pavement. Styrene-butadiene-styrene block copolymer (SBS) is an important asphalt modifier, which can effectively improve the high and low temperature performance and rutting resistance of asphalt. At present, the SBS modifier used in industry is mainly wet modification, that is, SBS is ground and mixed with asphalt by means of high-speed shearing to make SBS modified asphalt, and then used in construction. However, the wet process has very obvious limitations, requiring special modification equipment, and the process is complicated; the heating temperature of the asphalt is high, and it is easy to age; the c...

AI Technical Summary

Problems solved by technology

However, for the dry direct injection process, since the SBS modifier particles are directly mixed into the mixing pot to form a mixture, it is difficult to specifically characterize the dispersion state of the SBS modifier in it. The conventional method is to complete the mixing process. The mixture is tested for various indicators, and the dispersion state of the SBS modifier in the asphalt is indirectly characterized by the test results of the asphalt mixture

However, this method is often highly variable, inaccurate, not specific, and lacks scientific and rigorous

In addition, the traditional visualization-mathematical calculation method (VC method) to measure SBS content / distribution is limited by its measurement principle, and its data collection methods are mostly estimation methods. Even if the results are close to the accurate value through mathematical processing, the actual value However, it cannot be detected by this method

[0004] Therefore, for the dry process, how to ensure that the dry SBS modifier is evenly dispersed in the asphalt mixture in the process of mixing with the aggregate has not been a good analysis method.

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