华南理工大学学报(自然科学版) ›› 2024, Vol. 52 ›› Issue (8): 126-137.doi: 10.12141/j.issn.1000-565X.230692

• 材料科学与技术 • 上一篇    下一篇

基于分层剥离试验的温拌橡胶沥青改性机理研究

于华洋1(), 张正2, 邓溢豪1, 虞将苗1()   

  1. 1.华南理工大学 土木与交通学院,广东 广州 510640
    2.中建四局水利能源发展有限公司,广东 广州 510665
  • 收稿日期:2023-11-05 出版日期:2024-08-25 发布日期:2024-02-09
  • 通信作者: 虞将苗(1979—),男,博士,教授,主要从事道路工程结构与材料研究。 E-mail:huayangyu@scut.edu.cn
  • 作者简介:于华洋(1988—),男,博士,副教授,主要从事道路工程结构与材料研究。E-mail: huayangyu@scut.edu.cn
  • 基金资助:
    国家自然科学基金资助项目(51808228);广东省自然科学基金资助项目(2023A1515030287)

Study on the Modification Mechanism of Warm Asphalt Rubber Based on Stage-Extraction Method

YU Huayang1(), ZHANG Zheng2, DENG Yihao1, YU Jiangmiao1()   

  1. 1.School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510640, Guangdong, China
    2.China Construction Fourth Bureau Water Resources and Energy Development Co. , Ltd. , Guangzhou 510665, Guangdong, China
  • Received:2023-11-05 Online:2024-08-25 Published:2024-02-09
  • Contact: 虞将苗(1979—),男,博士,教授,主要从事道路工程结构与材料研究。 E-mail:huayangyu@scut.edu.cn
  • About author:于华洋(1988—),男,博士,副教授,主要从事道路工程结构与材料研究。E-mail: huayangyu@scut.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(51808228);the Natural Science Foundation of Guangdong Province(2023A1515030287)

摘要:

为探究温拌橡胶沥青(WAR)的性能影响机理,选取70#基质沥青、2种温拌剂和2种粒径的胶粉,制备了2种橡胶沥青(AR)和4种温拌橡胶沥青。通过固液相分离得到制备沥青样品的液态组分和不溶胶粉,创新性地利用分层剥离法对不溶胶粉混溶区成分进行逐层提取,通过试验研究建立胶粉吸附偏好特性与橡胶沥青高、中温流变性能间的联系,明确温拌橡胶沥青的改性机理。试验结果表明:橡胶沥青高温抗车辙性能和低温抗开裂性能的提升得益于不溶胶粉在沥青中产生的颗粒效应和可溶胶粉成分发挥的改性作用;橡胶沥青中温耐久性能的提高和黏度的增大主要归因于不溶胶粉中产生的颗粒效应;不同类型温拌剂对橡胶沥青流变性能的影响有所区别。有机类温拌剂的加入在提升橡胶沥青的高温抗车辙性能和中温耐久性能方面更为显著;化学类温拌剂的加入则在提升橡胶沥青的低温抗开裂性能方面更为有效;橡胶沥青液态组分中具有较小的相对分子质量的轻质成分更容易被胶粉吸附至其混溶区中;有机类温拌剂对胶粉的吸附偏好性几乎没有明显影响,而化学类温拌剂的加入不仅减少了液态组分中较大相对分子质量成分的比例,还削弱了胶粉的吸附偏好性;胶粉的吸附偏好性有利于提高橡胶沥青的高温性能和耐久性能。

关键词: 温拌橡胶沥青, 流变性能, 改性作用, 颗粒效应, 吸附偏好

Abstract:

To investigate the performance impact mechanism of warm asphalt rubber (WAR), 2 types of asphalt rubber (AR) and 4 types of warm asphalt rubber were prepared by using 70# base asphalt, 2 types of warm mixing agents, and 2 grain sizes of crumb rubber modifier. Liquid phase and insoluble crumb rubber modifier for prepared asphalt samples were obtained by the solid-liquid phase separation. The staged extraction method was innovatively employed to systematically extract components in the insoluble crumb rubber modifier blending zone layer by layer. Through experiments, the study established the connection between the preferential absorption of crumb rubber modifier and high- and medium-temperature rheological properties represented by asphalt rubber and clarified the modification mechanism of warm asphalt rubber. Test results indicate that the improvement of asphalt rubber’s high-temperature rutting resistance and low-temperature cracking resistance performance are attributed to the particle effect generated by insoluble crumb rubber modifier in asphalt and the modification effect of the soluble components of crumb rubber modifier. The improvement of fatigue resistance at medium temperature and the increase in viscosity of asphalt rubber is mainly attributed to the particle effect generated in the insoluble crumb rubber modifier. Different types of thermal mixture have different effects on the rheological properties of asphalt rubber. The addition of the organic warm mix additive is more significant in enhancing the high-temperature resistance to rutting and medium-temperature resistance to fatigue performance of asphalt rubber. The addition of the chemical warm mix additive proves to be more effective in improving the low-temperature resistance to cracking performance of asphalt rubber. The lighter components with smaller relative molecular mass in the asphalt rubber liquid phase are more easily absorbed by the crumb rubber modifier into its blending zone. The organic warm mix additive has almost no significant effect on the preferential absorption of crumb rubber modifier, while the addition of the chemical warm mix additive not only reduces the proportion of large relative molecular mass components in the liquid phase but also weakens the preferential absorption of crumb rubber modifier. The preferential absorption of crumb rubber modifier is beneficial for improving the high-temperature and fatigue resistance properties of asphalt rubber.

Key words: warm asphalt rubber, rheological property, modification effect, particle effect, preferential absorption

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