废胎胶粉改性沥青性能研究

以斜胶胎和子午胎两种废胎胶粉作为改性剂,对20、40和80目3种粒径以及20%掺量下改性沥青进行了常规性能、动态剪切(DSR)和弯曲梁流变(BBR)试验,系统研究了废胎种类、胶粉粒径对改性沥青高温和低温性能的影响;采用差热分析(DSC)试验方法,分析了20%胶粉掺量下胶粉粒径对沥青的改性效果和胶粉改性沥青的热力学性能。结果表明:掺入废胎胶粉后的沥青,其高温抗车辙、低温抗裂和抗疲劳等性能改善明显,斜交胎胶粉的改性效果优于子午胎胶粉;较大粒径的胶粉对沥青的软化点、抗车辙因子、弹性恢复改善效果较好,而低温性能与胶粉粒径小的改性沥青相当。综合性价比,建议采用斜交胎胶粉,胶粉的最佳粒径为20目,掺量为20%。

Performance Research on Crumb Rubber Modified Asphalt

Taking rubber powder of ramp and meridian waste tire as the modifier,the modified asphalt tests of routine performance,dynamic shear rheometer(DSR) and bending beam rheometer(BBR)are conducted with three kinds of particle size,including 20 mesh,40 mesh and 80 mesh,as well as the condition of 20% mixing amount.The modification mechanism and thermodynamics performance of rubber powder are researched from the experiments of differential scanning calorimetry.The results indicate that modified asphalt performances of anti-rutting,anti-fatigue and low temperature performance are improved after rubber powder modification;the rubber powder modification effect of ramp tire is superior to that of meridian tire;the improvement effect of penetration index,anti-rutting factor and elastic recovery of modified asphalt is better in the case of greater particle size rubber powder,and the low temperature performance is similar to that of smaller particle size;so considering the performance-price ratio,the optimal particle size is 20 mesh and the optimal mixing amount is 20%.