Abstract: To achieve the resource utilization of solid waste from waste rubber powder and plastic, and to enhance the road performance of rubber-plastic alloy modified asphalt pavement, a pretreatment technology for rubber-plastic alloy modifiers was proposed, which involved desulfurization activation of rubber powder using composite waste edible oil and microwave irradiation, as well as grafting of maleic anhydride onto plastic. The rules of different pretreatment methods influencing the rheological behaviors of rubber-plastic alloy modified asphalt were analyzed by adopting conventional asphalt performance test, dynamic shear rheometer (DSR), multiple stress creep recovery (MSCR) test, and bending beam rheometer (BBR) test. Meanwhile, the microstructural characteristics and modification mechanisms were investigated by using Fourier transform infrared spectrometer (FTIR) and fluorescence microscope (FM). The results indicate that the optimal dosage of the rubber-plastic alloy modifier is 32%. After activation and grafting pretreatment, the softening point difference of the rubber-plastic alloy modified asphalt decreases, the rutting factor increases, the bending creep stiffness decreases while the creep rate increases. Pretreatment effectively improves the compatibility of the rubber-plastic alloy modified asphalt and enhances its capability of high-temperature resistance to permanent deformation and performance of low-temperature crack resistance. The pretreated rubber-plastic alloy modifier is more uniformly dispersed in asphalt with reduced agglomeration, and the modification process is physical. The rubber-plastic alloy modified asphalt prepared with rubber powder activated by microwave irradiation and plastic grafted with maleic anhydride exhibits superior comprehensive performance.

Key words: highway engineering; solid waste utilization; rubber-plastic alloy modified asphalt; activating pretreatment; rheological properties; microscopic mechanism

摘要： 为实现废旧橡胶粉和塑料的固废资源化利用，提升橡塑合金改性沥青路面的路用性能，提出了采用复合废食用油与微波辐照对橡胶粉进行脱硫活化、塑料接枝马来酸酐的橡塑合金改性剂预处理技术。采用沥青常规性能试验、动态剪切流变仪（DSR）、多应力蠕变恢复试验（MSCR）、弯曲梁流变试验（BBR）剖析了不同预处理方式对橡塑合金改性沥青流变行为的影响规律；采用红外光谱仪（FTIR）与荧光显微镜（FM）对其微观构造及改性机理进行分析。研究表明：橡塑合金改性剂最佳掺量为32%，活化接枝预处理后的橡塑合金改性沥青软化点差值减小；车辙因子增大；弯曲蠕变劲度变小，蠕变速率增加；预处理有效的改善了橡塑合金改性沥青的相容性，提高了改性沥青的高温抗永久变形能力和低温抗裂性能。预处理后的橡塑合金改性剂在沥青中分散更加均匀，团聚现象减弱，且改性过程为物理改性。胶粉经微波辐照活化、塑料接枝马来酸酐预处理的橡塑合金改性沥青综合性能更优。

关键词: 道路工程；固废利用；橡塑合金改性沥青；活化预处理；流变性能；微观机理