摘要
为了提高胶粉掺量,采用了化学活化技术成功制备出了不同掺量胶粉改性沥青(内掺30%~40%),并分析了超高掺量胶粉改性沥青的性能,同时对改性机理进行了探讨。结果表明:超高掺量胶粉改性沥青黏度与常规掺量胶粉改性沥青相当,其低温抗裂性和均匀性能均优于常规掺量胶粉改性沥青;超高掺量胶粉改性沥青高温抗车辙性略有下降,但其疲劳极限温度低于常规掺量胶粉改性沥青,具有更低的玻璃化转变温度,可以适用于更低的环境温度。利用红外光谱和扫描电子显微镜分析了超高掺量胶粉改性沥青的微观结构。发现超高掺量胶粉改性沥青化学成分与常规橡胶粉改性沥青基本相同,橡胶粉的粒径分布主要集中在10~100μm,超高掺量胶粉改性沥青中还均匀分布着亚微米级橡胶粉颗粒和溶解的橡胶粉。最后探讨了超高掺量胶粉改性沥青的机理,在保留一部分橡胶粉弹性核心的基础上,减小了橡胶粉在沥青中的粒径,把部分橡胶粉降解为溶于沥青的橡胶小分子,创造了一种新的相分布形式(橡胶粉-橡胶小分子-沥青三元共混体系),提高了胶粉的掺量,改性沥青的性能也得到显著提升。
In order to increase the content of crumb rubber, the modified asphalt with different contents of crumb rubber(incorporated 30%-40%) are successfully prepared by using chemical activation technology. The performance of modified asphalt with ultra-high content of crumb rubber is analyzed, and the modification mechanism is discussed. The result shows that(1) the viscosity of modified asphalt with ultra-high content of crumb rubber is equivalent to that of conventional rubberized asphalt, and its low-temperature crack resistance and uniformity are better than those of conventional rubberized asphalt;(2) the high-temperature rutting resistance of ultra-high content crumb rubber modified asphalt is slightly reduced, but its fatigue limit temperature is lower than that of conventional rubberized asphalt, which has lower glass transition temperature and can be applied to lower environmental temperatures. The microstructure of the modified asphalt with ultra-high content of crumb rubber is analyzed by using infrared spectroscopy and scanning electron microscope. It is found that the chemical composition of the modified asphalt with ultra-high content of crumb rubber is basically the same as that of conventional rubberized asphalt, the particle size distribution of crumb rubber is mainly concentrated in 10-40 μm, and the ultra-high content of crumb rubber modified asphalt is evenly distributed with sub-micron crumb rubber particles and dissolved crumb rubber. Finally, the mechanism of modified asphalt with ultra-high content of crumb rubber is discussed. On the basis of retaining a part of the elastic core of crumb rubber, the particle size of crumb rubber in the asphalt is reduced, and part of the crumb rubber is degraded into small rubber molecules soluble in asphalt, creating a new phase distribution form(crumb rubber-rubber small molecule-asphalt ternary blend system), thus the content of crumb rubber is increased and the performance of the modified asphalt is significantly improved.
作者
蔡斌
王佳
相宏伟
焦依坤
CAI Bin;WANG Jia;XIANG Hong-wei;JIAO Yi-kun(Hebei Traffic Technologies Materials Co.,Ltd.,Shijiazhuang Hebei 050091,China;R&D Center of Road Construction,Maintenance Technical Materials and Equipment for Transport Industry,Shijiazhuang Hebei 050091,China;Hebei Provincial Communications Planning Design and Research Institute Co.,Ltd.,Shijiazhuang Hebei 050091,China)
出处
《公路交通科技》
CAS
CSCD
北大核心
2022年第9期16-22,109,共8页
Journal of Highway and Transportation Research and Development
基金
河北省交通运输厅科技项目(Y-201616)。
关键词
道路工程
超高掺量胶粉改性沥青
微观分析
改性机理
性能
road engineering
ultra-high content crumb rubber-modified asphalt
micro analysis
modification mechanism
performance
