Study On Performance Of Plasticizer DOA Modified Asphalt And Mixture In High And Low Temperature

The temperature shrinkage crack of asphalt pavement is one of the main diseases of pavement for a long time,especially in the cold climate area,a serious problems such as surface voids,sinkage,frost boiling,etc.caused by cracks seriously affect the using function and service life of road.Asphalt binder,as one important part of asphalt pavement,plays a very important role on low-temperature anti-cracking property.Since plasticizer has a positive influence in lowering the melting point and plasticity of plastic,in view of that,the paper is attempting to modify asphalt binder with Bis(2-ethylhexyl)adipate to improve the lowtemperature anti-cracking property of asphalt/asphalt mixture,and be some reference for the research of asphalt modified materials.In this research,zhonghai-70 matrix asphalt and four kinds of modified asphalt with different plasticizer dosages are as the research targets and some experiments including the three main indexes,Brookfield viscosity,Bending beam rheometer(BBR),Dynamic shear rheometer(DSR),Infrared Spectroscopy(IR),Short-time aging test,Freeze-thaw splitting test,Low temperature bend test and Wheel tracking test were conducted to study the influence law of plasticizer and plasticizer dosages on modifying asphalt or asphalt mixture.The whole research mainly focuses on the following aspects:(1)the study on rheological property,low temperature anti-crack property,high temperature stability property and aging resistance of modified asphalt with different plasticizer dosages;(2)the exploration of modification mechanism about plasticizer modified asphalt binder based on IR technology;(3)the study on low temperature anti-crack property,high temperature anti-rutting property and moisture resistance of modified asphalt mixture;(4)the study on low temperature anti-crack property,high temperature anti-rutting property of plasticizer/Anti-Rut Agent composite modified asphalt mixture.Through a series of laboratory tests,the following conclusions are obtained:(1)the test results of dynamic rheological test show that the proportion of viscous component in modified asphalt increases within the frequency range10-2~102Hz,and the more plasticizer DOA content is,the more big the proportion of viscous component become;(2)Compared with matrix asphalt,the temperature sensitivity of modified asphalt increases,and the temperature susceptibility of modified asphalt decrease along with increase of plasticizer DOA content;(3)considering several index including low-temperature ductility,equivalent fraass breaking point,glass transition temperature(Tg)and the value of creep rate m,the low-temperature anti-cracks property of modified asphalt is improved significantly,and the more plasticizer DOA content is,the better the low-temperature anti-cracks property is;(4)considering several index including softening point,60? apparent viscosity and rutting factor,the plasticizer DOA has a negative influence on modified asphalt binder,and the more plasticizer DOA content is,the worse the high temperature stability is;(5)the plasticizer DOA has a positive influence on antiaging property of modified asphalt binder,but the improvement has no direct relationship with the content of plasticizer DOA;(6)based on IR technology,the plasticizer modified asphalt is a simple physical blending substance,and there is no chemical reaction between plasticizer DOA and asphalt;(7)along with the increase of plasticizer DOA content,the low-temperature cracks resistance of modified asphalt mixture become better,while the rutting resistance become worse;(8)the plasticizer DOA has a positive influence on moisture resistance of modified asphalt mixture,but the improvement has no direct relationship with the content of plasticizer DOA;(9)plasticizer DOA/Anti-Rut Agent composite modified asphalt mixture has a good performance in both aspects of low-temperature cracks resistance and high-temperature rutting resistance.