活化胶粉复合改性沥青混合料的路用性能评价

Evaluation of Road Performance of Activated Rubber Powder Composite Modified Asphalt Mixture

为评价双螺杆活化胶粉复合SBS改性沥青及其混合料的低温性能,用测力延度、半圆弯曲和裂缝扩展性能试验分别测试了SBS改性沥青、未活化胶粉复合SBS改性沥青和双螺杆活化胶粉复合SBS改性沥青的低温性能指标,并采用熵权法对测力延度指标进行优选,通过荧光显微镜和四组分试验对3种沥青的性能变化进行机理分析.结果表明:测力延度指标中最大屈服点可有效表征双螺杆活化胶粉复合SBS改性沥青的低温性能;双螺杆活化过程中交联键被打开,并与SBS形成稳定的交联网络结构,显著提高了改性沥青混合料的高温性能和抗水损害性能.

To evaluate the low-temperature performance of double screw activated rubber powder composite SBS modified asphalt and its mixture,the low-temperature performance indicators of SBS modified asphalt,non-activated rubber powder composite SBS modified asphalt,and twin-screw activated rubber powder composite SBS modified asphalt were tested by force ductility,semi-circular bending,and overlay test.The entropy weight method was used to optimize the force ductility indicators.The mechanism of performance changes of the three types of asphalt was analyzed through fluorescence microscopy and four component testing.The results indicate that the maximum yield point of the force ductility index can effectively characterizes the low-temperature performance of twin-screw activated rubber powder composite SBS modified asphalt.During the twin-screw activation process,crosslinks are opened and a stable crosslink network structure is formed with SBS,significantly enhancing the high-temperature performance and resistance to water damage of the modified asphalt mixtures.