Study On Adhesion Performance Of PAC-13 Permeable Asphalt Mixture

The research on the application of permeable asphalt pavement?PA?at home and abroad and the long-term monitoring of the road found that although the permeable asphalt mixture has the advantages of drainage,noise reduction and so on,the long-term monitoring results show that there are various degree of disease problems in all sections of road.For example,water damage,dispersion and so on.The existence of water in asphalt pavement has an adverse effect on the durability of pavement,resulting in a variety of pavement diseases.Although the existence of water will not cause cracks,permanent deformation and spalling diseases,but the presence of water will aggravate its severity and scope.Due to the high cost of maintenance,a large number of researchers have shifted their attention from repairs to preventive measures,which cause high costs to the relevant road authorities and inconvenience to road users.The failure mechanism of water damage is the failure of adhesion between asphalt and aggregate.A large number of testing methods and theoretical studies have made the research of adhesion more accurate and quantitative.However,most of the articles are aimed at the requirements of ordinary asphalt mixture to study the adhesion of asphalt aggregate combination,but to meet the durability requirements of permeable asphalt mixture,the content of research on the adhesion of asphalt aggregate combination is less.In this paper,the adhesion of PAC-13 mixture to bitumen aggregate combination is studied.The influencing factors and evaluation methods are analyzed from the point of view of aggregate,asphalt and mixture.Finally,the test results are comprehensively analyzed.To meet the requirements of asphalt-aggregate combination adhesion of PAC-13 mixture.The main contents of the study are as follows:?1?The improved water immersion test and surface energy method are used to evaluate the adhesion of asphalt aggregate combination.For the surface energy method,it is found that the surface energy index ER₂ can more obviously distinguish the adhesion between asphalt and aggregate,and for the same asphalt or the same aggregate,the linear relationship between the spalling rate and the surface energy index ER₂ is better.?2?The self-made modified asphalt with high viscosity can meet the requirement of asphalt permeable asphalt mixture,and the road performance of the sample is good.The water stability of the bitumen-aggregate combination may not meet the requirements if its adhesion is good.It is suggested that high viscosity asphalt be used as binder of permeable asphalt mixture.?3?When the adhesion index is used as the base,the base asphalt does not meet the requirements,the adhesion of asphalt B and asphalt C to the four aggregates meets the requirements,and for asphalt A,when the alkali value of aggregate is?0.8,The adhesion of asphalt A to aggregate can meet the requirements.When considering the road performance of PAC-13,the base value of aggregate should be?0.7when the combination of high viscosity asphalt and basalt is considered as the criterion of three freeze-thaw cycles,that is,when high viscosity asphalt is adopted,the base value of aggregate should be greater than 0.7.?4?When the adhesion index is used as the base,when the asphalt viscosity20000Pa s index is satisfied,the corresponding bituminous acid value is 3.33,that is,for the permeable asphalt mixture,the acid value of the asphalt needs to be more than 3.33.When considering the road performance of PAC-13,the combination of asphalt C and basalt meets the requirements of the three freeze-thaw cycles,that is,the viscosity of high viscosity asphalt should be?32118Pa s,and the corresponding acid value of asphalt should be?3.8.?5?With the bituminous C basalt assemblage as the criterion for judging the adhesion of the asphalt aggregate combination of permeable asphalt mixture,the surface energy index of the asphalt aggregate combination of the permeable asphalt mixture ER₂?0.455,and the spalling rate corresponding to the surface energy index is?5.