温度和剪切速率对 Sasobit 改性沥青粘度影响研究

摘要

In this study,dynamic viscosity was measured at temperature ranges from 28 ℃ to 130℃ at 6 ℃ interval.From viscosity analyses it can be concluded that there exists a critical temperature for a Sasobit modified asphalt such that above the critical temperature Sasobit reduces the viscosity and below that temperature Sasobit increases the viscosity.Also,the shear rate dependency of steady state viscosity of asphalt binders with and without Sasobit was analyzed in this study with in the range of 0.002 5 /s to 250 /s.With the addition of Sasobit,PG 64 -22 at 64 ℃ becomes a shear-thinning liquid.The shear rate de-pendency increases with an increase in percent of Sasobit.Similar effects of Sasobit are observed at 100℃ in reduced level and shear rate dependency with the addition of Sasobit is almost negligible at 124 ℃.Also,the rate of change of viscosity is higher at higher shear rates and lower at lower shear rates.%该研究中，在28～130℃温度范围，间隔6℃测量动态粘度（η’）。从粘度分析中可得出以下结论：对 Sasobit 改性沥青存在一个临界温度，在临界温度之上 Sasobit 降低粘度；在临界温度之下 Sasobit 增加粘度。此外，在0.0025～250 s －1剪切速率范围内，分析了掺加及未参加 Sasobit 沥青的稳态剪切黏度对剪切速率的依赖性。掺加 Sasobit 后，在64℃下 PG64－22沥青变为剪切变稀型流体。剪切速率依赖性随着 Sasobit 掺量的增加而增加。在100℃下观察到了 Sasobit 相似的效果。对 PG76－22M沥青，在所有3个温度下，随着 Sasobit 掺量增加，剪切速率依赖性增加。这表明，如果现场实际的剪切速率高于粘度测量所使用的剪切速率，目前正使用的拌和及压实温度可能较低。