摘要
普通沥青混合料按照ASTM D2493的等黏原则可以确定沥青混合料的施工温度,但不适宜于改性沥青混合料。通过4种SBS改性沥青混合料在不同压实温度下的旋转压实试验建立毛体积相对密度与压实温度的关系,由此得到混合料最佳压实温度,根据该最佳压实温度下的黏度与剪切速率关系,得到黏度0.28 Pa.s对应的剪切速率大约在60 s-1。由此建议改进的改性沥青等黏原则测黏剪切速率为60 s-1,而不是ASTM D2493规定的6.8 s-1,结果表明新方法确定的改性沥青混合料施工温度可降低10℃以上。
The equiviscous principle in accordance with ASTM2493 is developed using unmodified asphalt binders, but it is not suitable to some polymer-modified asphalt binders. Through the results of 4 types of Styrene-Butadiene-Styrene Block Copolymer (SBS) modified asphalt mixtures with the compaction of Superpave Gyratory Compactor (SGC) at different temperatures,the relationships between bulk specific gravity and compaction temperature are established. Then the optimal compaction temperature is obtained, and under this optimal temperature the relationship between the viscosity and Brookfield shear rate of SBS modified asphalt is determined. The measurement shear rate of the viscosity 0.28 Pa·s is about 60 s^-1.So the shear rate of 60 s^-1 ,rather than ASTM suggested 6.8 s^-1 ,is suggested to test the SBS modified asphalt in the new equiviscous principle. The results show that the construction temperature according to the modified equiviseous principle is above 10℃ lower than ASTM 2493.
出处
《公路》
北大核心
2010年第1期161-168,共8页
Highway
基金
西部交通建设科技项目
项目编号200831881210