Application Research On Adhesion Between Asphalt And Aggregate Based On Surface Energy Theory

Asphalt mixture water damage has been a major problem for China ’s highwayconstruction, it is quite complex for mechanics theory, the theory of chemical reactions,molecular orientation theory, electrostatic theory to calculate each the evaluation of theperformance of asphalt and stone adhesion, only qualitatively describe the adhesion ofasphalt and stone formation mechanism. According to the 《Technical Specifications forConstruction of Highway Asphalt Pavement》(JTG F40-2004)boiled method and theimmersion method are applied to evaluate the adhesion of the asphalt and aggregate,lacks quantitative indicators and easily affected by human factors.In this paper, thesurface energy theory were put forward to quantitatively evaluate the adhesion of theasphalt and aggregate. By the washout performance and interfacial bond strength test toverify that the truth of applicability for evaluation of asphalt and aggregateadhesion.Receiving the relationship between the theory of surface energy indicatorsand the performance of asphalt and aggregate. Providing another quantitative evaluationmethods and standards is good or bad in the future to evaluate the adhesion of asphaltand aggregate.First of all, through the determination of contact angle, Seton method and hangingmethod test determined asphalt and aggregate surface parameter, basing on the theory ofsurface energy analyzed the adhesion mechanism of asphalt and stone, respectivelyanalyzed the blocking property of conditions with and without water. Under anhydrousconditions use the amount of change in contact angle and failure stage of the Gibbs freeenergy as evaluation index of asphalt and stone surface adhesion performance. Underwater conditions use the cohesive function of asphalt and the Gibbs free energy changeof contact angle and flood stage as evaluation index of asphalt and stone anti waterdamage performance.Then, using ultraviolet spectrometer determined stone adsorption capacity of matrixasphalt and the shear strength, the two kinds of indoor tests verified the adhesionproperties in an anhydrous condition of the asphalt and stone interface system, theresults show that the two test results are agree to the theoretical analysis results ofsurface energy. And through the non relevant theoretical analysis on the impact ofasphalt and stone material interface bond performance influence factors analyzedcorrelation degree, the test show that relevance between the theory index of surface energy and asphalt and stone interface bond performance is good.Then, using the SHRP net adsorption experiment and the boiled method to determinethe water level and the asphalt membrane peeling rate in process of water boiling.Thesetwo kinds of tests are used to verify the adhesion capabilities of asphalt stone interfacesystem in the presence of water. The results show that these two tests’ results areconsistent with the results of the surface energy theoretical analysis. Analysis oninfluence of asphalt and stone material anti washout performance influence factorswhich is made according to the gray correlation theory shows that a good relevanceexists between the index of surface energy theory and the properties of stone interfaceagainst water damage performance. And establish the relational expression between theindex of the surface energy theory and water level.Finally, the lime slurry treatment and adding anti-stripping agent treatment are bothused to modify the acidic aggregate asphalt system, and then using the theory of surfaceenergy to make analysis. The results show that the treatment of using anti-strippingagent for acid stone mortar is more effective.