摘要
为系统研究生物质重油对道路回收沥青的再生效果及其机理,分别采用高低温流变试验、原子力显微镜技术和红外光谱扫描等多尺度方法,比较分析了沥青老化前后以及不同生物质重油掺量下沥青的宏观流变特性、微观形貌特征以及化学结构等变化规律,并对不同尺度指标之间的内在联系进行了讨论分析。结果表明:沥青在服役过程中在吸氧反应、氢键缔合等作用下发生老化,其微观形貌中蜂状结构数量减少但个体变大,在宏观上表现为粘度、复数模量显著增大,高温性能增强而低温抗裂性能明显变差。随着生物质重油掺量的增大,回收沥青在化学组成和微观形貌上产生逆老化的变化,粘度和复数模量逐渐降低,且低温性能得到有效改善,说明生物质重油对道路回收沥青具有较好的再生效果。此外,为确保再生沥青的高低温性能的平衡,本研究中所采用的的生物质重油掺量建议控制在5%~21%范围内。
In order to systematically evaluate the effect of biomass heavy oil on regeneration of recycled asphalt,macro-rheological,micro-morphology and chemical structures of asphalt before and after asphalt aging,and asphalt under different biomass heavy oil content were compared. For this purpose,high-low temperature rheological tests,atomic force microscopy tests and infrared spectroscopy tests were conducted. The results show that asphalt is aged with oxygen absorption reaction and hydrogen bond association during the service of asphalt pavement. Besides,the viscosity and complex modulus of asphalt increase significantly,and the high-temperature performance is enhanced while the low-temperature crack resistance deteriorates obviously,which is associated with that the number of bee-like structure of asphalt decreases but the size becomes larger after aging. With the increase of biomass heavy oil content,the chemical composition and micro-morphology of recycled asphalt change inversely,the viscosity and complex modulus gradually decrease,and the low-temperature performance is effectively improved,indicating that biomass heavy oil has a good regeneration effect on recycled asphalt. In addition,with the consideration of high and low temperature performances of recycled asphalt,the content of biomass heavy oil used in this study is recommended to be controlled in the range of 5%-21%.
作者
樊兴华
薛振华
FAN Xing-hua;XUE Zhen-hua(Department of Road and Bridge Engineering,Shaanxi Railway Institute,Weinan 714000,China)
出处
《硅酸盐通报》
CAS
北大核心
2019年第5期1477-1483,共7页
Bulletin of the Chinese Ceramic Society
