废胶粉/天然沥青复合改性沥青抗老化性能及其机理研究

Research on Anti-aging Property of Compound Modified Asphalt based on Waste Rubber Powder and Natural Asphalt

为提高沥青的抗老化性能,采用废旧轮胎加工制得的废胶粉(CR)、特立尼达湖天然沥青(TLA)、印尼布敦岩天然沥青(BRA)对70号基质沥青复合改性。通过3种沥青老化试验和傅里叶红外光谱试验,以黏度老化指数、复数模量老化指数及蠕变劲度老化指数为主要评价指标,以官能团的变化为次要指标,评价复合改性沥青的抗老化性能。结果表明:掺量为10%CR+20%BRA复合改性沥青的抗老化性能最优;废胶粉和天然沥青都能改善沥青的抗老化性能,两种掺量的改善效果能起到叠加作用;复合改性沥青通过抑制基质沥青老化中含氧官能团的产生达到改善抗老化性能的效果。

In order to improve the anti-aging performance of asphalt, 70 matrix asphalt is modified by using waste rubber powder made from waste tire, Trinidad Lake natural asphalt and Indonesia Buton rock asphalt. The viscosity aging index, complex modulus aging index and creep stiffness aging index are taken as the main evaluation indexes, to evaluate the anti-aging performance of composite modified asphalt, the modification of functional groups is used as a secondary index. The results show that: composite modified asphalt with 10% CR and 20% BRA has the best anti-aging properties;both waste rubber powder and natural asphalt can increase the anti-aging performance of asphalt, and the two combinations’ improving effects can be superimposed;composite modified asphalt can improve the anti-aging effect by inhibiting the generation of oxygen-containing functional groups in aging matrix asphalt.