Study on the Properties of Different Bio-asphalts and the High-Temperature Performance of Bio-asphalt Mixtures
Bio-oil is gradually being used in asphalt pavements as a sustainable renewable energy source.To explore the effect of different bio-oils on the properties of asphalt and asphalt mixtures,corn stover oil(CS),castor seed oil(CB),and rice husk oil(RH)asphalt were prepared,the changes in the basic properties of bio-asphalts before and after aging were analyzed using the three major indexes,the temperature susceptibility coefficient and the needle penetration index as the evaluation factors;the effect of bio-oil on the high-temperature properties and relative molecular mass of asphalt was investigated by dynamic shear rheology test and gel permeation chromatography;marshall tests,high-temperature rutting and indirect tensile fatigue tests were carried out to investigate the effect of bio-oil on the high-temperature performance and fatigue characteristics of asphalt mixtures.The results of the study show that:Of the three main indicators,RH bio-oil has increased recombinant fraction and better high-temperature performance,and CB has increased the light fraction content of the bitumen and better low-temperature crack resistance and fluidity;the RH bitumen has a smaller needle penetration-temperature susceptibility coefficient,after aging,CS and CB were 6.25％and 2.17％higher than RH asphalt at 3％blending,respectively,and the temperature sensitivity of RH bitumen is lower;the complex shear modulus of RH asphalt was 7.27％lower than that of matrix asphalt,the rutting factor was 9.09％higher than that of matrix asphalt,with higher rutting resistance,and the large molecular weight percentage was 15.58％higher than CS asphalt,with stronger intermolecular forces;the Marshall modulus,dynamic stability and fatigue life of asphalt mixtures increased with increasing RH dosage and were 4.01％,28.32％and 58.23％higher than that of matrix asphalt mixtures at 6％,respectively,and the high temperature performance and fatigue resistance characteristics of RH asphalt mixtures were enhanced.The study is important for the rapid development of bio-asphalts in the road industry.
road engineeringbio-asphaltsrelative molecular massasphalt mixturehigh temperature performance
万方数据
