Study And Application Of Hard Asphalt For High Modulus Asphalt Concrete

Since asphalt binder belong to viscoelastic material, under the action of high temperatureand shear stress of driving, it occurs viscous flow inevitably, resulting in permanentdeformation and rut. To solve the problem of rutting, researchers aroud the world have done alot of research work, but mostly were from asphalt mixture gradation. So how to start fromthe asphalt binder, by improving its plastic properties and increasing the whole modulus ofasphalt mixture to reduce the rut is particularly important.Currently, there is no technology standard for hard asphalt dedicated for High ModulusAsphalt Concrete yet in domestic.Usually, the30#and50#low-grade asphalt binder whichmeet the GB/T15180-2000and JTG F40-2004are called hard asphalt. But the penetrationindex of30#and50#low-grade asphalt binder does not meet the requirements of theEuropean standard EN13924, and when applied to High Modulus Asphalt Concrete AC EME,it is difficult to meet the technical requirements of NF EN13108-1for complex modulus≥14000MPa. Therefore, the30#and50#low-grade asphalt binder only belong to the categoryof common asphalt binder, not hard asphalt which is in accordance with European standardsEN–13924with15to251/10mm or10-201/10mm penetrationand mainly be used in HighModulus Asphalt Concrete AC EME. Its ductility in mesotherm temperature and wax contentare not required, but the changes of softening point，135℃viscosity，Fraass point ect, havebeen strictly restricted.As the nature of crude oil and processing technology of hard asphalt have a greaterinfluence on the high and low temperature performance, and there is no unified technicalstandards of hard asphalt provided for applicator as theoretical basis when choosing itstypes.This paper will carry out system study on selecting raw materials and processingtechnology for producing hard asphalt, and will give a detailed evaluation about theperformance of High Modulus Asphalt Concrete.Experimental results showed that the hardasphalt produced by propane deasphalting process of karamay petrochemical company hadexcellent water stability, high temperature stability and high modulus performance, withexcelent application prospect.Through this study, a new understanding for the technology of High Modulus AsphaltConcrete and its dedicated hard asphalt were obtained, and this will provide experimentalevidences for promotion and application of High Modulus Asphalt Concrete and its dedicatedhard asphalt. It also provides a new thinking and methods to solve the pavement rutting forhighway asphalt pavement construction.