蒙脱土改性沥青的抗热氧老化性能研究  

Research on Thermo-Oxidative Aging Resistance of Montmorillonite Modified Asphalt

作　　者：李哲宇 LI Zhe-yu(Shanxi Transportation Survey&Design Institute Co.,Ltd.,Taiyuan,Shanxi 030032,China)

机构地区：[1]山西省交通规划勘察设计院有限公司,山西太原030032

出　　处：《山西交通科技》2022年第6期9-12,共4页Shanxi Science & Technology of Transportation

摘　　要：沥青在高温条件下发生的热氧老化会引起各种路面病害,包括开裂、剥离和坑槽等,降低沥青路面的使用寿命。为提升沥青在服役期间的抗热氧老化性能,选用蒙脱土(MMT)作为沥青改性剂,采用0wt%、2wt%、4wt%和6wt%用量的MMT制备改性沥青,分别进行了旋转薄膜烘箱(RTFOT)和压力老化(PAV)试验,模拟短期和长期的热氧化老化。通过室内试验对基质沥青、MMT改性沥青及其老化后试样进行常规物理性能和流变特性测试,分析蒙脱土改性剂对沥青抗热氧老化性能的影响规律。结果表明,掺入MMT可显著提升沥青结合料的G^(*)和G^(*)/sinδ,δ随之减小。MMT改性沥青结合料在不同老化程度下流变指标的变化小于基础沥青结合料,说明MMT改性沥青结合料具有优异的流变性能,MMT改性剂能够显著改善沥青的抗热氧老化性能,且最佳掺量为4wt%。The thermo-oxidative aging of asphalt at high temperatures can cause various pavement diseases,such as cracking,stripping,and ditches,reducing the service life of asphalt pavement.To improve the thermos-oxidative aging resistance of the asphalt during service life,montmorillonite(MMT)was selected as the asphalt modifier to prepare the modified asphalt with the dosages of 0wt%,2wt%,4wt%,and 6wt%.Rolling thin film ovens(RTFOT)and pressurized aging vessels(PAV)were used to simulate the short-and longterm thermo-oxidative aging,respectively.The common physical properties and rheological properties of matrix asphalt,MMT modified asphalt,and their aging samples were tested by indoor tests to analyze the influence of MMT modifier on the thermo-oxidative aging resistance of asphalt.The results showed that adding MMT can significantly improve the G^(*)and G^(*)/sinδof the asphalt binder,and theδdecreased accordingly.The change in the rheological index of MMT modified asphalt binder under different aging degrees was smaller than that of matrix asphalt binder,indicating excellent rheological properties of MMT modified asphalt binder.MMT modifier can significantly improve the thermo-oxidative aging resistance of asphalt,with an optimal dosage of4wt%.

关 键 词：道路工程 改性沥青 蒙脱土 抗热氧老化 

分 类 号：U414[交通运输工程—道路与铁道工程]