道路沥青五次老化再生微观分析

发布时间：2018-06-02 18:32

本文选题：沥青 + 老化规律　；参考：《湖南科技大学》2015年硕士论文

【摘要】：随着我国经济的迅速发展,沥青路面作为我国的高等级路面已经普遍存在。与水泥混凝土路面相比,沥青路面表面平整;不用设置接缝;扬尘少;而且维修方便;开放交通快。沥青路面行车舒适、养护简单等优点使得沥青路面越来越多的被采用。然而沥青路面的温度敏感性强,高温易变软,低温易变脆变硬的缺陷又使得沥青路面达到一定的使用年限后就需要进行大、中修,这不仅会造成沥青混合料的浪费,拌合、摊铺沥青混合料产生的废气也在一定程度上会污染环境,这与现阶段我国推崇的“资源节约型、环境友好型”的发展模式是相悖的。一方面,为了沥青混凝土路面的继续普及,另一方面,为了建设“资源节约型、环境友好型”社会,对沥青路面的老化机理的探究以及运用一些先进的生产技术和设备对沥青进行再生产利用已经非常迫切。本文从模拟沥青老化开始着手,测试沥青的性能指标,分析沥青老化的机理,然后在此基础上通过多次再生效果的对比找出最佳再生的再生剂的添加值,并测试再生的性能指标,得出沥青随老化时间和次数的增加,沥青的针入度逐渐减小,软化点逐渐升高,延度值逐渐减小,用再生剂对老化沥青一次老化再生和多次老化再生,沥青的性能都能大致恢复到老化前水平。同时用微观分析进一步得知和验证了沥青老化后的吸氧氧化和组分的变化,运用傅里叶红外光谱和原子力显微镜来研究沥青在老化和再生的微观方面信息。通过试验数据和结构的变化的对比分析,红外光谱曲线图表明,在用薄膜烘箱模拟沥青老化过程中,沥青中的C-H官能团被氧化成C=O羰基官能团,S元素被氧化成S=O亚砜基,随着老化时间和老化次数的增加,羰基和亚砜基的含量也逐渐增加,加入再生剂后,沥青中的C=O和S=O官能团含量大致减少,但沥青在多次老化再生过程中,第一次和第二次再生后羰基和亚砜基官能团并没有比第一次和第二次老化要少,说明再生过程并不是老化过程的逆反应,原子力显微镜图片很好的说明,沥青老化后沥青质含量的增加,再生后沥青质含量减少,符合沥青老化再生四组分的变化规律。从宏观和微观两方面入手来探究沥青的老化再生机理,宏观、微观相结合,为研究沥青老化再生提供了一条新的路径,对沥青深层的理解和开发利用等提供了非常宝贵的理论依据。
[Abstract]:With the rapid development of China's economy, asphalt pavement as a high-grade pavement in China has been widely existed. Compared with cement concrete pavement, the surface of asphalt pavement is flat; no joint is set; dust is less; maintenance is convenient; and open traffic is fast. Asphalt pavement is used more and more because of its advantages such as comfortable driving and simple maintenance. However, the defects of asphalt pavement such as high temperature sensitivity, high temperature becoming soft, low temperature becoming brittle and hard make asphalt pavement need to be repaired and repaired after a certain service life, which will not only cause waste of asphalt mixture, but also mix. The exhaust gas produced by paving asphalt mixture will also pollute the environment to a certain extent, which is contrary to the development mode of "resource saving and environment friendly" that our country adores at present. On the one hand, in order to continue to popularize asphalt concrete pavement, on the other hand, in order to build a "resource-saving, environment-friendly" society, It is very urgent to explore the aging mechanism of asphalt pavement and to use some advanced production technology and equipment for asphalt reproduction. In this paper, the performance index of asphalt is tested, and the mechanism of asphalt aging is analyzed. The test results show that the penetration of asphalt decreases, the softening point increases and the ductility decreases with the increase of aging time and times. Asphalt performance can be roughly restored to the pre-aging level. At the same time, the changes of oxygen absorption and composition of asphalt after aging were further obtained and verified by microcosmic analysis. Fourier transform infrared spectroscopy (FTIR) and atomic force microscope (AFM) were used to study the microscopic information of asphalt aging and regeneration. By comparing and analyzing the experimental data and the structural changes, the IR curves show that the C-H functional group in the asphalt is oxidized to the S element of the Con O carbonyl functional group during the aging process of the asphalt simulated by the thin film oven, and the S element is oxidized to the Schio sulfoxide group. With the increase of aging time and aging times, the contents of carbonyl group and sulfoxide group also increased gradually. The functional groups of carbonyl and sulfoxide after the first and second regeneration are not less than those of the first and second aging, indicating that the regeneration process is not the inverse reaction of the aging process. The content of asphaltene increases after asphalt aging and decreases after regeneration, which accords with the change rule of four components of asphalt aging regeneration. From the macro and micro aspects to explore the mechanism of asphalt aging regeneration, macro and micro combination, for the study of asphalt aging regeneration provides a new path, It provides a very valuable theoretical basis for the deep understanding and exploitation of asphalt.
【学位授予单位】：湖南科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U414

【参考文献】