TerminalBlend废胶粉-纳米SiO_2改性沥青粘温关系及低温韧性

Viscosity-temperature Relationship and Low Temperature Toughness of Terminal Blend Crumb Rubber-nano SiO_2 Modified Asphalt

为评价废胶粉-纳米复合改性沥青的高温抗变形性、流变特性及低温韧性,制备了湿法Terminal Blend胶粉-纳米SiO_2复合改性沥青,并借助旋转粘度、针入度、软化点、5℃和15℃延度试验进行了性能表征,还基于实测表观粘度拟合了复合改性沥青粘度-温度关系。结果表明:掺加纳米SiO_2后,复合改性沥青针入度减小,软化点升高,高温抗变形性能得到改善,且纳米SiO_2掺量越大,改善越显著;纳米SiO_2掺量4%时5℃延度比未掺前提高约37.5%。此外,复合改性沥青高温粘度较基质沥青和未纳米改性时有所增加,但135℃粘度不超过1500cP,施工和易性良好;粘度数据拟合还表明在135~200℃温度域内,复合改性沥青粘温关系符合较好的指数关系。

To evaluate the high temperature deformation temperature toughness of crumb rubber （CR）-nano modified asphalt, the wet process terminal blend CR-nano SiO- modified binders with different nano contents were prepared and characterized using rotational viscosity, penetration, ring ＆ ball softening point as well as ductility （5℃, 15℃） tests. The viscosity-temperature relationships of these binders were established through regression on the viscosity data. Results indicate that addition of nano SiO2 into terminal blend CR binder improved the high temperature binder performance, and the 5℃ ductility could be enhanced by 37.5 %. In addition, although the binder viscosity increased after adding nano SiO2, its 135℃ viscosity did not exceed 1500cP, indicating CR-nano modified binders showed satisfactory workability. The regression also shows that a good exponential relationship was found between the viscosity and temperature of modified binder in the temperature domain of 135-200℃.