橡胶粉改性沥青性能优化实验与作用机理分析

Study on Performance Optimization Experiments and Modification Mechanism of Rubber Modified Asphalt

以橡胶粉的目数、掺量、沥青拌和时间和拌和温度作为4个评价因素,建立4因素3水平正交试验配比方案,采用各因素水平下的改性沥青的针入度、软化点、延伸度、弹性恢复以及布氏旋转黏度五个指标评价沥青性能,并分析了各因素在橡胶沥青中的作用机理。结果表明:40目橡胶粉在掺量为25%,拌和温度为195℃搅拌1 h得到的改性沥青的性能最好。通过橡胶粉物理膨胀与化学脱硫作用,在合理的橡胶粉目数、掺量、搅拌时间以及搅拌温度下,沥青的塑性和黏性得到提高,改善了沥青的温度敏感性和耐老化性能。

This article took rubber powder mesh, dosage, mixing time and temperature as the four evaluation factors to establish four factors-three levels orthogonal proportion program. It adopted penetra- tion, softening point, elongation, elastic recovery, and Brookfield rotational viscosity etc. five performance indicators of modified asphalt in each factor and level to evaluate the performance of modified asphalt, and analyzed the physical and chemical rubber asphalt modification mechanism. The results showed that： The best performance of modified asphalt is mixing amount 25% of 40 mesh rubber powders and stirring tem- perature at 195~C and stirring 1 h to get. The physical expansion of rubber powder and chemical desulfu- rization cause the improvement of asphalt plastic and viscous within a reasonable mesh rubber powder, dosage, mixing time and mixing temperature. It improves the temperature sensitivity and aging resistance of asphalt.