Detection method of surface energy parameters of road aggregates

Abstract

The invention discloses a road aggregate surface energy parameter detection method. The method comprises the following steps: selecting three chemical reagents with known surface energy base parameters; calculating aggregate specific surface areas respectively obtained through adsorbing steams of the three reagents through adopting a steam adsorption technology; respectively solving the diffusion pressures of the three reagents on the surface of aggregates through a Gibbs equation; establishing an equilibrium equation that the sum of the reduction value of surface energy of the surface of the aggregates adsorbing the steams of the three reagents and the adhesive energy of the reagents equals to the adhesion energy of the reagents; and solving through a ternary equation to obtain the nonpolar component, the polar acid component and the polar alkali component of the surface energy of the aggregates. The test method selected against an aggregate sample is reasonable, has substantially higher test precision than present test methods, has high test operation automation degree, and is simpler than the present methods.

Description

technical field [0001] The invention belongs to the field of road engineering, and specifically relates to a detection method of road aggregate surface energy parameters. Background technique [0002] The surface free energy method is a relatively advanced test method for accurately quantifying the adhesion performance of asphalt and aggregates in the world. Its basic principle is to obtain three basic parameters of the surface energy of asphalt and aggregates (non-polar dispersion component) gamma LW , polar acid component γ + , Polar base content γ - ), combined with the surface energy formula to calculate the cohesive energy of asphalt itself and the adhesion energy between asphalt and aggregates, so as to accurately evaluate the matching performance between asphalt and aggregates. Fatigue cracking, healing and water damage properties of materials. [0003] Since the surface free energy method can accurately quantify the matching between asphalt and aggregates, it has...

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Problems solved by technology

In recent years, some scholars have also proposed to use the microcalorimeter method to test the surface energy of aggregates through the principle of thermodynamics. After the aggregate surface is immersed in a known test reagent, the change of the total energy of the system and the thermal evolution (called immersion enthalpy) can be determined by the immersion enthalpy. The relationship between wet enthalpy and interface energy is solved to obtain the surface energy parameters of aggregates, but it is only applicable to powdery aggregates, and the assumption that "wetting enthalpy is twice the wetting entropy" does not apply to all aggregate samples , in addition, the specific surface area of ​​the aggregate still needs to be obtained by the adsorption method in the calculation process, the test process is cumbersome and the test result processing method is not very reasonable

[0005] At this stage, the surface energy testing method of aggregates has the following disadvantages: the test samples are either in powder form or after surface grinding and polishing, ignoring the influence of aggregate surface characteristics or mineral components on the surface energy test; the test is mainly based on human-operated readings , increase the human error in the test process; the test environment is relatively open, which inevitably increases the influence of impurities in the air on the surface energy of the aggregate, and the test at room temperature cannot effectively ensure that the test temperature is constant

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