基于热、光耦合条件下SBS改性沥青老化机理研究

发布时间：2018-05-19 13:00

  本文选题：SBS改性沥青 + 耦合条件　； 参考：《重庆交通大学》2015年硕士论文

【摘要】：SBS改性沥青在自然环境及行车条件作用下性能发生严重劣化,使路面不再满足使用要求。成熟的老化沥青再生技术能为道路建设提供可循环使用的沥青资源,研究SBS改性沥青的老化机理能为沥青再生提供技术参考。本文依托国家自然科学基金《热光水耦合条件下SBS改性沥青老化机理研究及高性能再生剂开发》开展研究。对耦合老化前后的改性沥青进行性能测试时发现,改性沥青老化后针入度减小、粘度增大、软化点升高,与基质沥青变化规律一致。但SBS改性沥青随老化程度加深,其车辙因子G*/sinδ在某些时刻反而减小,这与基质沥青老化后抗车辙能力增强的规律不同。一般而言,基质沥青抗老化性能好,对应的改性沥青抗老化性能相对较好,但也受到沥青制备及老化过程的影响。两种类型的改性剂对改性沥青的抗老化性影响无明显差异。70℃温度下,温度在耦合老化作用中的贡献率达到40%~70%,50℃温度下温度对老化的贡献率在30%~50%之间,即温度越高,温度对老化的贡献率越大。耦合老化后,改性沥青中含氧官能团羟基、羰基、亚砜基含量增加,表明沥青老化过程中发生了氧化反应,而来源于SBS聚合物中的丁二烯基团逐渐减少,说明聚合物出现降解,同时改性沥青老化后发生结构异化,芳香度增加,脂肪侧链长度增加。沥青相均分子量变大,聚合物均相分子量减小。经综合分析,改性沥青耦合老化过程中主要的化学变化为氧化及分子结构异化。以灰色关联度法对改性沥青的宏观性能指标与微观化学结构进行对比分析,以羰基指数和芳香度分别代表改性沥青耦合老化氧化和结构异化两个方面的老化程度,发现芳香度与针入度、软化点、135℃粘度的关联程度在0.7~0.8之间,羰基指数与针入度、软化点、135℃粘度的关联度在0.6~0.9之间,说明热光耦合老化中氧化和结构异化引起的改性沥青性能指标变化程度不一。
[Abstract]:The performance of SBS modified asphalt under the action of natural environment and driving conditions is seriously deteriorated, which makes the pavement no longer meet the requirements of use. Mature aging asphalt regeneration technology can provide recycled asphalt resources for road construction. The study of aging mechanism of SBS modified asphalt can provide technical reference for asphalt recycling. In this paper, the aging mechanism of SBS modified asphalt and the development of high performance regenerating agent were studied by the National Natural Science Foundation of China. It is found that the penetration, viscosity and softening point of the modified asphalt after aging are decreased and the softening point is increased, which is consistent with that of the matrix asphalt. However, the rutting factor G*/sin 未 of SBS modified asphalt decreases at some time with the increase of aging degree, which is different from the law of increasing rutting resistance of base asphalt after aging. Generally speaking, the base asphalt has good anti-aging performance, and the corresponding modified asphalt has better anti-aging performance, but it is also affected by the asphalt preparation and aging process. There is no obvious difference between the two kinds of modifiers on the aging resistance of modified asphalt. At 70 鈩，

本文编号：1910195