为研究环氧沥青的高温性能,制备了环氧树脂掺量不同的改性沥青进行动态剪切流变试验并探究了固化时间对环氧沥青流变性能的影响。结果表明,随着环氧树脂含量的增加及固化时间的延长,沥青的复数剪切模量G*和车辙因子G*/sinδ增大,相位角δ和蠕变变形量减小,这表明环氧树脂改性使沥青的刚性明显增强,有利于提高其抗车辙性能。基于分子动力学模拟了环氧沥青的流变行为,通过对内聚能密度(CED)、自由体积分数(FFV)和均方位移(MSD)的分析,揭示了环氧树脂改善沥青高温稳定性的内在机理。从宏观和分子尺度研究了环氧沥青的高温性能,为丰富环氧沥青材料的研究方法和评价手段提供了新的思路。
In order to investigate the high temperature stability of epoxy asphalt (EA),modified asphalts with different epoxy resin contents were prepared.The effect of curing time on the rheological properties of epoxy asphalt was explored by dynamic shear rheometer (DSR).The experimental results showed that as the epoxy resin content and curing time increased,the complex shear modulus G* of the asphalt and the rutting factor G*/sinδ increased,while the phase angle δ and creep deformation decreased,which indicated that the epoxy resin modification significantly enhanced the rigidity of the asphalt and helped to improve its rutting resistance.Simultaneously,the rheological behavior of epoxy asphalt was simulated based on molecular dynamics.The analysis of cohesive energy density (CED),free fraction volume (FFV) and mean square displacement (MSD) revealed the internal mechanism of epoxy resin improving the high temperature stability of asphalt.The study evaluated the high temperature stability of epoxy asphalt from the macroscopic and nanoscopic scales,and provided a new idea for the research and evaluation methods of epoxy asphalt materials.
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基金资助
国家自然科学基金(52172063);湖南省教育厅优秀青年科研项目(19B038)
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