不同类型橡胶粉与SBS复合改性沥青的性能特征分析

Performance Characteristics Analyses of Asphalt Modified by Different Types of Rubber Powder and SBS

以橡胶粉类型(硫化橡胶粉和脱硫橡胶粉)、SBS(苯乙烯-丁二烯-苯乙烯嵌段共聚物)及其掺量等因素为变量,分析改性沥青三大指标、力学指标、存储稳定性等性能特征以及改性机理。结果表明:硫化橡胶粉改性沥青对掺量有较强的敏感性,在1.5%SBS和橡胶粉复合改性时,SBS对硫化橡胶粉改性沥青影响程度较脱硫胶粉而言更为显著;在20%掺量下硫化橡胶粉对沥青的破坏能量提升更明显,且SBS在硫化橡胶粉沥青内部分散效果更好,对其破坏能量改善效果更为显著;硫化橡胶粉和脱硫橡胶粉改性沥青都会存在离析现象,相对而言脱硫橡胶粉沥青的离析更为显著,且SBS能更明显改善脱硫橡胶粉沥青的稳定性,在道路工程中推荐使用硫化橡胶粉和SBS复合改性沥青。

Effects of rubber powder type(vulcanized rubber powder and desulfurized rubber powder),SBS(styrene-butadiene-styrene block copolymer)and their contents on performance characteristics of modified asphalt,such as three main indexes,mechanical indexes,storage stability were studied.The mechanism of asphalt modification was analyzed.The results show that asphalt modified by vulcanized rubber powder is more sensitive to the dosage.The influence of SBS on asphalt modified by vulcanized rubber powder is more significant than that of asphalt modified by desulfurized rubber powder when 1.5%SBS and rubber powder are used together.The damage energy of modified asphalt increases more obviously when the content of vulcanized rubber powder is 20%.And SBS has better dispersion in asphalt modified by vulcanized rubber powder binder and has more remarkable improvement effect on its destructive energy.There exists segregation phenomenon in asphalt modified by vulcanized rubber powder and desulfurized rubber powder.However,the segregation of asphalt modified by desulfurized rubber powder is more evident.The SBS can significantly improve the stability of asphalt modified by desulfurized rubber powder.Asphalt modified by vulcanized rubber powder and SBS is recommended in road engineering.