Test method of asphalt and coarse aggregate adhesiveness

Abstract

The invention discloses a test method of asphalt and coarse aggregate adhesiveness. The test method comprises the following steps: preparing an asphalt cement material for test and five coarse aggregate samples meeting the requirements, measuring masses M1 to M5 of coarse aggregates by using an analytical balance, scanning the coarse aggregates by using a 3D area determinator to obtain surface areas A1 to A5, then heating and drying the aggregates, soaking the aggregates in the asphalt adhesive which is pre-heated to a flowing state, so that the coarse aggregates can be taken out after being sufficiently coated with the asphalt adhesive; and curing an asphalt membrane on the surface of the aggregate, gradually lifting the sample by using a wire, after the sample is completely solidified, placing the sample into a self-made instrument, and performing the washing and poaching test. After the test, the masses M'1 to M'5 of the sample are re-measured, and the thickness of the remaining structural asphalt membrane which can still cover the surface of the coarse aggregate sample can be calculated by virtue of the formula. By adopting the test method, the defects of the boiling method that the influence of the human factor is serious and the evaluation index is not quantified can be overcome, and the unpredictable test error of the mass loss method that the free asphalt which does notcover the aggregate is also calculated as the boiling mass loss can also be avoided.

Description

technical field [0001] The invention relates to a test method for the adhesion between asphalt and coarse aggregate, and belongs to the technical field of road asphalt mixture test. Background technique [0002] Since the birth of asphalt pavement, it has achieved considerable development in my country by virtue of its good driving comfort, anti-skid performance and low noise. However, early damage has always existed in the development of asphalt pavement, and water damage is one of the main causes of early damage to asphalt pavement. The water damage of asphalt pavement refers to the fact that in the presence of water, after repeated action of traffic load and temperature expansion and contraction, water gradually invades the interface between asphalt and aggregate, and the asphalt film gradually changes from The surface of the aggregate is peeled off, which eventually leads to the loss of the cohesive force between the asphalt and the aggregate. Therefore, the adhesion b...

AI Technical Summary

Problems solved by technology

The water boiling method is commonly used in engineering to test the adhesion of asphalt and aggregates, but this method has the defects that human factors are greatly affected and the evaluation index is not quantitative.

The mass loss method is an evaluation method improved on the basis of the water boiling method. Although this method proposes a quantitative index to evaluate the adhesion between asphalt and aggregates, there are still large unavoidable experimental errors.

For example, after the coarse aggregate immersed in the asphalt binder is taken out and left to stand, there are different degrees of excess free asphalt on the surface of the soaked coarse aggregate, and this part of free asphalt does not participate in the coating of structural asphalt and aggregate, but In this method, it will be calculated into the loss of mass, causing unpredictable experimental errors

Therefore, the quality loss index cannot accurately evaluate the quality of adhesion

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