SEAM改性沥青流变特性

Rheological properties of SEAM modified asphalt binder

采用动态剪切流变试验测试了沥青胶浆在原始状态、旋转薄膜老化状态及压力老化状态下的复数模量、相位角、车辙因子、疲劳因子。采用弯曲梁流变试验测试了沥青胶浆的蠕变劲度及蠕变劲度变化率。结果表明,长期老化后,改性剂质量分数为10%的SEAM改性沥青车辙因子显著增强,且疲劳因子满足SHRP沥青胶结料规范。随着改性剂含量的增加,沥青蠕变劲度增加,蠕变劲度变化率降低。综合分析上述各项流变指标可知,SEAM改性剂对沥青流变特性影响显著,适当含量(质量分数为10%)的SEAM改性剂可以有效改善沥青流变效果,而高含量(质量分数为20%以上)的SEAM改性剂会使沥青流变效果降低。

The complex modulus,the phase angle,the wheel tracking factor and the fatigue factor of asphalt binder at the original state,at RTFOT state and at PAV state were tested by a dynamic shear rheometer.The creep stiffness and its time rate were tested by a bending beam rheometer.The results show that the wheel tracking factor of the SEAM modified asphalt binder with modifier mass fraction of 10% enhanced significantly,and the fatigue factor met the demands of the SHRP standard for asphalt binder.The creep stiffness of asphalt binder increased and its time rate decreased with the increase of the modifier content.From the obtained rheological index data it can be concluded that the SEAM modifier affects significantly the rheological properties of asphalt binder.The SEAM modifier with appropriate content（mass fraction about 10%） improves the rheological effect of asphalt binder,while the high content modifier（mass fraction more than 20%） stands opposite.