全透式沥青路面专用高黏度改性沥青性能对比

Contrastive on performance of fully permeable asphalt pavement dedicated high-viscosity modified asphalt

为了制备一种全透式沥青路面专用高黏度改性沥青,采用自制改性粒子(SR)与SBS粒子为复配改性剂,对基质沥青进行复合改性。通过荧光显微照相、针入度试验、延度试验、软化点试验、薄膜老化试验、动力黏度试验及布氏黏度试验等,对自制高黏度改性沥青性能进行表征,并与SK90#基质沥青、橡胶沥青、SBS改性沥青进行性能对比。结果表明:各改性材料在基质沥青中分散良好,自制高黏度改性沥青中的SR粒子作为高弹嵌挤单元提高了沥青交联网状结构的稳定性;与基质沥青相比,改性沥青具有较高的软化点和延度,以及较低的针入度(25℃);自制高黏度改性沥青的动力黏度高达230kPa·s,明显高于橡胶沥青和SBS改性沥青;动态剪切流变试验(DSR))中自制高黏度改性沥青高温分级达到PG82℃,较SBS改性沥青和橡胶沥青提高1个等级,较基质沥青提高4个等级,高温变形可恢复性能最强;4种沥青的原样和薄膜老化后沥青中以自制高黏度改性沥青的车辙因子随温度变化最为缓慢,高温敏感性最弱,耐老化性能优异;弯曲梁流变试验(BBR)中,SBS改性沥青和自制高黏度改性沥青的低温分级均达到PG-18℃,较基质沥青和橡胶沥青高1个等级,但自制高黏度改性沥青的蠕变劲度较小,蠕变速率较大,具有更强的低温柔性。

To prepare dedicated high-viscosity-modified asphalt for a fully permeable asphalt pavement,self-made SR particles and SBS particles were used as combined modifiers to modify the matrix asphalt. The performance of self-made high-viscosity-modified asphalt was characterized by fluorescence microscopy and penetration,ductility,softening point,film oven,kinetic viscosity,and Brookfield viscosity testing.The performance of this asphalt was comparedwith the performances of SK90#base asphalt,rubber asphalt,and SBS-modified asphalt.The results show that the modified materials have good dispersion in asphalt,and the SR particles,as highly elastic interlocking units,strengthened the stability of the cross-linked network structure.Compared to the base asphalt,the modified asphalts have a high softening point and ductility and low penetration(25℃).The kinetic viscosity of dedicated high-viscosity-modified asphalt reaches 230 kPa·s,which is significantly higher than that of rubber asphalt and SBS-modified asphalt.A dynamic shear rheological test shows that the self-made high-viscosity-modified asphalt’s high temperature grade reaches PG82℃,which is one grade higher than SBS-modified asphalt and rubber asphalt,and four grades higher than base asphalt,with the strongest restorability of high-temperature deformation.The rutting factors of dedicated high-viscositymodified asphalt changes the slowest with increasing temperature,with the weakest sensitivity to high temperature and the strongest aging resistance of the original and postrotating film oven test rutting factors of four types of asphalts.The low temperature grade of SBS-modified asphalt and that of the dedicated high-viscosity modified asphalt reach PG-18℃,of a bending beam rheometer test,which is one grade higher than base asphalt and rubber asphalt,and the dedicated high-viscosity-modified asphalt with a better creep stiffness and a higher creep rate exhibits good low-temperature flexibility.7 tabs,6 figs,25 refs.