橡胶沥青混合料中橡胶沥青老化程度的表征

摘要

通过室内模拟橡胶沥青及橡胶沥青混合料老化的试验方法,研究了不同老化程度下橡胶沥青及橡胶沥青混合料回收沥青的基本性能,建立了橡胶沥青及回收沥青性能关系模型,并对橡胶沥青混合料进行了老化分级.结果表明,橡胶沥青混合料回收沥青的性能与橡胶沥青的真实老化性能存在一定的差异,其中旋转黏度试验值的标准偏差最小,采用旋转黏度多项式模型可由回收沥青的老化性能间接反映橡胶沥青混合料的真实老化程度;根据回收沥青的旋转黏度对橡胶沥青混合料进行老化分级:当旋转黏度不大于2.1 Pa·s时,老化等级为轻度老化;当旋转黏度大于2.1 Pa·s且不大于2.9 Pa·s时,老化等级为中度老化;当旋转黏度大于2.9 Pa·s时,老化等级为重度老化;通过扬冶公路橡胶沥青路面铣刨料中橡胶沥青的实际老化程度验证对应关系模型的拟合效果较好.%Through indoor simulated test method of aging rubber asphalt and its mixture,the basic performance was studied between rubber asphalt and recycled asphalt at different aging degree,the relationship model between the performance of rubber asphalt and recycled asphalt was established,and the aging grade of rubber asphalt mixture were determined.The results showed that the performance of asphalt recycled with rubber asphalt mixture was different from that of rubber asphalt.Among the performance,the standard deviation of the rotation viscosity test value was the minimum,and the rotation viscosity polynomial model could be used to indirectly reflect the actual aging degree of rubber asphalt mixture by the aging performance of recycled asphaAccording to the rotation viscosity of recycled asphalt,the aging grade of rubber asphalt mixture was determined.When the viscosity was less than 2.1 Pa · s,the aging degree of rubber asphalt mixture was mild;When the viscosity was greater than 2.1 Pa · s and less than 2.9 Pa · s,the aging degree of rubber asphalt mixture was moderate;When the viscosity was greater than 2.9 Pa · s,the aging degree of rubber asphalt mixture was severe.The actual aging degree of rubber asphalt in the old rubber asphalt pavement of Yangye high way could validate the corresponding model,and the fitting effect of the model was excellent.