Study On Modification Mechanism And Pavement Performance Of Oil Shale/SBS Modified Asphalt

At present,China's economy emphasizes not only the rapid development of the coastal developed cities,but also the joint development of all regions.In order to effectively link all regions of China,each region will achieve rapid economic growth in a complementary way of resources.It puts forward the requirement of high speed,high efficiency and heavy safety for transportation.The most important factors that influence the speed,efficiency and safety of transportation are the highway network system scientifically and the performance of roads.Asphalt pavement has many advantages,such as early opening,good anti skid resistance,high durability,low noise,high smoothness and easy maintenance.It is widely used in grade highways,especially in the construction of expressway.With the improvement of the development of economic construction in China,conventional asphalt pavement material has not reached the standard,so SBS modified asphalt has been widely used in our country.At present,most of the modified bitumen used in China's asphalt pavement is SBS modified asphalt.Although SBS modified asphalt has received extensive attention and recognition for its excellent performance,the degradation of the SBS molecules in the presence of heat,oxygen and ultraviolet radiation will affect its performance and the service life is greatly reduced because of the unsaturated double bonds in the molecule.In addition,because of the incompatibility between SBS modifier and asphalt,it is easy to stratification and segregation during storage and has a great influence on the storage stability of SBS modified bitumen.Because of the particularity of oil shale mineral properties and inorganic and organic matter components,their organic matter composition is similar to that of leaching,which is rich in saturated phenol and aromatic phenol.By adding oil shale mineral powder to SBS modified asphalt,the influence of oil shale mineral powder on the performance of SBS modified asphalt is studied.The optimum processing temperature and mixing time of oil shale /SBS modified bitumen were determined by the normal physical index test of asphalt,and the optimum processing temperature of the oil shale modified asphalt was determined by the test data.It was found that when the processing temperature was 170 ? and the stirring time was 60 min,the best preparation process of the oil shale /SBS modified bitumen was found.The softening point of SBS modified asphalt was increased,the penetration and ductility of SBS modified asphalt were reduced,the segregation and aggregation of SBS modifier in asphalt were slowed down,the storage stability of SBS modified asphalt was improved,and the viscosity of SBS modified asphalt was increased,and the complex shear modulus of SBS modified asphalt was obviously increased at temperature range of 50-62 ? and the modulus of the complex shear modulus of SBS modified bitumen was greatly increased.The phase angle improves the rutting resistance factor and improves the aging resistance of SBS modified asphalt.According to the analysis and comparison of the above performance,it is found that the best dosage of oil shale /SBS modified bitumen when the oil shale powder is added to the oil shale is 10%.Finally,the performance of oil shale /SBS modified asphalt mixture with 10% oil content is verified by experiments and compared with the data of SBS modified asphalt.The results showed that the high temperature and water stability of SBS modified bitumen /SBS modified asphalt increased obviously,but the low temperature cracking resistance decreased.