Study On Adhesion Of Interface Between Asphalt And Aggregate

The adhesion between aggregate and asphalt blinder is an important index to evaluate the anti-water damage ability,and it is also the foundation of the formation strength of asphalt mixture.This thesis discuss the properties of the interface adhesion between aggregate and asphalt blinder by the improved pull-out test through the pull-out force,the pull-out force loss rate and stripping rate.Based on the surface energy theory,the interface model of asphalt-aggregate interfacial adhesion and cohesive failure was established,and the effective interface energy WE and water stability evaluation index ER were proposed.Microscopic study of asphalt-aggregate interface was carried out by scanning electron microscopy.Finally,the water stability of the mixture was evaluated by Marshall test specimens.Through the pull-out test and asphalt mixture test,analysis of the effect of the aggregate temperature,soaking time,test temperature and the raw materials of asphalt and stone on interfacial adhesion of asphalt aggregate,and analyze various factors theory of the gray relational entropy,and the reproducibility of pull test results was studied by t test method.The results show that the limestone has better bonding property and water stability than granite and asphalt,and with the increase of the temperature of the stone aggregate,asphalt has better adsorption effect,the longer the immersion time,the worse the adhesion properties between asphalt and aggregate.It has certain guiding significance to improve the adhesion of asphalt and stone and enhance the ability of resisting water damage.Based on the surface energy theory,the adhesion work of asphalt aggregate system and peeling work before and after the addition of anti-stripping agent in the cohesion and adhesion failure were calculated,and then calculate the effective interfacial energy WE and water stability evaluation index ER.The relationship between the effective interfacial energy WE and the drawing force,and the relationship between the water stability evaluation index ER and the freeze-thaw splitting strength ratio TSR were established.Research shows that ER has a good correlation with TSR.So the water stability of ER to evaluate asphalt mixture is feasible in theory.Adding the anti-stripping agent makes the asphalt aggregate adhesion work increases,and the increase of ER.In addition,through the relationship between WE and pull-out force curve,the interface surface energy,pull-out force and stripping rate are well connected.And taking into account the adhesion failure and cohesive failure of these two cases.So that the interface failure theory calculation is more reasonable.Correlating the pullout test,the surface energy theory evaluation method with the current standard evaluation method of water stability.The relationship between the microscopic surface energy theory and the macro mechanical parameters is established.And so the adhesion between asphalt and aggregate can be evaluated comprehensively and comprehensively.