为了提高沥青混凝土的综合性能，利用废旧聚丙烯（PP）微塑料改性基质沥青，制备AC-13沥青混凝土，研究沥青及沥青混凝土的性能。结果表明：加入微塑料提高了改性沥青的抗变形能力和耐高温稳定性，也提高了沥青混凝土的力学性能、高温稳定性、低温稳定性和水稳定性。微塑料掺量为4%时，与基质沥青相比，改性沥青的25 ℃针入度降低20%，软化点提高12 ℃。微塑料掺量为4%时，与基质沥青混凝土相比，改性沥青混凝土的浸水马歇尔残留度（MS₀）和冻融劈裂抗拉强度比（TSR）分别提高11.6%和12.8%，动稳定度提高86%，车辙深度降低67.0%，空隙率（VV）降低14.6%，稳定度（MS）和饱和度（VFA）分别提高21.1%和7.8%，低温弯曲破坏应变提高35.6%。

In order to enhance the comprehensive property of asphalt concrete, waste polypropylene (PP) microplastics were utilized to modify the asphalt matrix, resulting in the preparation of AC-13 asphalt concrete. The study focused on the properties of both asphalt and asphalt concrete. The results show that the addition of microplastics improves the deformation resistance and high-temperature stability of the modified asphalt, as well as enhances the mechanical properties, high temperature stability, low temperature stability, and water stability of the asphalt concrete. With a microplastic content of 4%, compared to the matrix asphalt, the modified asphalt exhibits a 20% reduction in penetration at 25 ℃ and a 12 ℃ increase in softening point. At the same microplastic content of 4%, in comparison to the matrix asphalt concrete, the modified asphalt concrete shows an 11.6% increase in immersion Marshall residual (MS₀) and a 12.8% increase in freeze-thaw splitting tensile strength ratio (TSR), an 86% improvement in dynamic stability, a 67.0% reduction in rut depth, a 14.6% decrease in volume of air voids (VV), a 21.1% increase in Marshall stability (MS), a 7.8% increase in voids filled with asphalt (VFA), and a 35.6% increase in low-temperature bending failure strain.