| 摘要: |
| 采用动态剪切流变和弯曲梁流变试验，研究了胶粉复配反应性弹性体三元共聚物(RET)改性沥青经历短期及长期老化前后的高低温流变特性，并与SBS复配RET改性沥青进行了对比；通过原子力显微镜对胶粉复配RET，SBS复配RET改性沥青老化前后的改性机理进行了初步分析.结果表明：胶粉、RET的掺入能改善沥青老化前后的高温性能；相比于SBS复配RET，胶粉复配RET对短期老化前后沥青的高温性能改善更显著，且长期老化后其劲度模量增长幅度更低；随着RET掺量的增加，胶粉复配RET,SBS复配RET改性沥青老化前后的高温抗变形能力随之增强，其低温性能变化不大；胶粉复配RET改性沥青的微观形态中出现明显的“黑白斑点”结构，相较于SBS复配RET改性沥青，胶粉复配RET改性沥青老化后的黏结力与耗散能提高，弹性模量降低，抗老化性能更好. |
| 关键词: 道路工程 改性沥青 胶粉 流变特性 老化机理 |
| DOI：103969/j.issn.1007 9629201706014 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目(51478046) |
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| Rheological Properties and Aging Mechanism of Rubber Crumb Composite RET Modified Asphalt before and after Aging |
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CHANG Rui, HAO Peiwen
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Key Laboratory for Road Structure and Materials of Ministry of Transport, Changan University, Xian 710064, China
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| Abstract: |
| Through dynamic shear rheological(DSR) and bending beam rheological(BBR) test, the rheological properties of rubber crumb composite reactive elastomeric terpolymer(RET) modified asphalt before and after the aging at high and low temperature was investigated by comparing to SBS composite RET modified asphalt. The modification mechanism of rubber crumb composite RET and SBS composite RET modified asphalt before and after the aging was analyzed by atomic force microscopy(AFM). The results show that rubber crumb and RET can improve high temperature performance of asphalt before and after the aging. Compared with SBS composite RET modified asphalt, rubber crumb composite RET modified asphalt has a better high temperature performance, and the increasing range of stiffness modulus is lower after pressure aging vessel(PAV) treatment. With increasing the content of RET, the resistance deformation at high temperature of rubber crumb and SBS composite RET modified asphalt gradually enhanced, and anti cracking performance at low temperature of both is basically equal. Rubber crumb composite RET modified asphalt shows “black and white spots” structure in the microscopic morphology. To compare with SBS composite RET modified asphalt, cohesion and dissipation of rubber crumb composite RET modified asphalt remarkably improve after the aging, but the elastic modulus decreases. The rubber crumb composite RET modified asphalt has super anti aging performance. |
| Key words: road engineering modified asphalt rubber crumb powder rheological property aging mechanism |
