高模量沥青及沥青混合料性能研究

Research on Performance of High Modulus Asphalt and Asphalt Mixture

为掌握IMA增模剂对沥青及沥青混合料性能的影响,采用沥青常规试验、DSR试验研究沥青流变性能,通过车辙试验、低温小梁弯曲蠕变试验、浸水马歇尔试验、冻融劈裂试验以及单轴动态压缩模量试验研究AC-20C沥青混合料的路用性能及力学性能。结果表明:IMA的加入增强了沥青的高温性能,但对沥青的低温性能有所降低,7%掺量的IMA能够提升沥青软化点19.7℃,沥青针入度降低了42 mm,而延度下降了60 cm;IMA能够显著提高沥青混合料的高温稳定性,掺量达到7%之后,提升效果不显著;IMA的加入能够显著提升沥青混合料的低温抗裂性能,但IMA掺量增大至7%后,其破坏应变仅增大0.5%;IMA能够提升沥青混合料抗水损害性能与抗变形能力;考虑沥青及沥青混合料性能及经济性,推荐AC-20C沥青混合料的IMA最佳掺量为7%。

In order to explore the influence of IMA modifier on the performance of asphalt and asphalt mixture,in this paper the conventional binder tests and DSR test are used to study the rheological properties of asphalt.The rutting test,low temperature trabecular bending creep test,Marshall test,freeze-thaw splitting test and uniaxial dynamic compression modulus test are carried out to study the road performance and mechanical properties of AC-20 C asphalt mixture.The results show that the addition of IMA enhances the high temperature performance of the asphalt,but reduces the low temperature performance of the asphalt.Adding 7%IMA can increase the softening point of the asphalt by 19.7℃,and the penetration of the asphalt is reduced by 42 mm.The ductility is reduced by 60 cm;IMA improves the high temperature performance of asphalt;and IMA can significantly improve the high temperature stability of the asphalt mixture.After the content reaches 7%,the improvement effect is not significant;the addition of IMA can significantly improve the low temperature crack resistance of the asphalt mixture performance,but when the IMA content is increased to 7%,its failure strain only increases by 0.5%.IMA can improve the water damage resistance and deformation resistance of asphalt mixtures.Considering the performance and economic performance of asphalt and asphalt mixtures,the optimal IMA content of AC-20 C asphalt mixture is 7%.