多聚磷酸与SBS复合改性沥青及其混合料抗老化性能研究

Study on Anti-aging Performance of Polyphosphate acid and SBS Modified Asphalt and Its Mixture

改善沥青混合料的抗老化性能,对于提高沥青路面的使用寿命有重要意义,基于室内模拟老化试验,采用低温弯曲试验和小梁疲劳试验研究了紫外线老化与热老化前后多聚磷酸(PPA)掺量对SBS改性沥青及其混合料抗老化性能和低温抗裂性能的影响。试验结果表明:PPA有效的提高了复合改性沥青高温荷载作用下模量的弹性分量比例,改善了复合改性沥青及其混合料的高温抗变形能力,但也会对复合改性沥青混合料的低温性能有负面影响,多聚磷酸的掺加能改善复合改性沥青的温度敏感性和老化前后的抗疲劳耐久性,增大PPA可显著提高老化后复合改性沥青混合料的低温抗裂性,PPA对SBS改性沥青的改性机理在于PPA能与SBS改性剂粒子共同交织形成空间网络结构,PPA与沥青质胶团中的亚砜基发生酯化反,增强了SBS改性剂在沥青中的交联作用。

improve the asphalt anti-aging properties, is important to improve the durability of the asphalt pavement, based on indoor simulation aging tests, using low-temperature bending test and trabecular fatigue were involved to study the influence of polyphosphate content on anti-aging properties and cracking resistance of SBS modified asphalt and its mixture, before and after heat aging and UV aging. The results showed that： PPA effectively improve the elastic modulus of the ratio of the weight of the composite modified asphalt temperature under load, to improve its high-temperature composite modified asphalt mixture resistance to deformation, but also on the composite modified asphalt the low temperature properties have a negative impact, Adding polyphosphate compound modified asphalt can improve fatigue durability and temperature sensitivity before and after aging, increasing the PPA can significantly improve aging compound modified asphalt mixture at low temperature cracking resistance, PPA SBS Modified asphalt modification mechanism that PPA with SBS modifier particles together to form a network structure interwoven, esterification reaction and asphahene micelles sulfoxide group occurred enhanced cross-linking agent in SBS modified asphalt.