碳纳米管接枝玄武岩纤维沥青胶浆的电愈合行为及机制
Electrically healing behavior and mechanism of asphalt mortar with carbon nanotube grafted basalt fibers
柳力 1刘磊鑫 1刘朝晖 1杨程程 1邱毛宁1
作者信息
- 1. 长沙理工大学 交通运输工程学院,长沙 410114
- 折叠
摘要
自愈合功能路面是当前道路工程研究的热点,其中通电发热是实现沥青路面自愈合的重要手段.为赋予沥青胶浆导电特性,以玄武岩纤维(BF)为连通基体,碳纳米管(CNTs)为导电相,运用化学接枝方法,提出了一种碳纳米管接枝玄武岩纤维(CNTs/BF)的制备工艺;通过电阻率、微观形貌、表面元素及官能团变化等表征试验,确定CNTs与BF最佳的接枝时间;设计CNTs/BF胶浆复数剪切模量和延度通电愈合试验,分析了CNTs/BF胶浆的通电愈合效果;联用红外热成像技术和数字图像散斑变形监测技术(DIC),分析了CNTs/BF胶浆的电愈合行为,揭示其愈合机制.研究结果表明:接枝 3 h时CNTs/BF的电阻率下降 6个数量级,碳(C)元素质量分数和Si-O-Si峰面积相比原样BF分别提高了 23.96％和 60.54％,说明CNTs接枝BF最佳时间为 3 h;CNTs/BF胶浆的愈合指数均高于BF和CNTs胶浆,0.3wt％掺量时复数剪切模量愈合指数相比 BF胶浆和 CNTs胶浆分别提升了 14.7％和 18.6％,延度愈合指数分别提升了 22.43％和 16.76％,说明CNTs/BF最佳掺量为 0.3wt％;红外热成像显示CNTs/BF胶浆的温度提升速率相比BF和CNTs胶浆分别提升123.53％和 533.53％,说明CNTs/BF胶浆具有局部升温特性;DIC显示CNTs/BF胶浆在裂缝处愈合高差达1.86 mm,较 BF和 CNTs胶浆分别提升了 77.99％和 160.14％,裂缝呈现定向愈合,并基于此揭示了CNTs/BF胶浆的通电愈合机制.研究成果为CNTs/BF在道路工程的应用提供重要参考.
Abstract
Self-healing functional pavement is the current hot spot of road engineering research,in which electrical healing plays a key role in enabling asphalt pavement to mend itself.To endow the asphalt mortar with conductive properties,a preparation process of carbon nanotubes grafted to basalt fibers(CNTs/BF)was proposed by using basalt fibers(BF)as the connecting matrix and carbon nanotubes(CNTs)as the conductive phase via a chemical grafting method.Characterization tests such as resistivity,micro-morphology,surface element and functional group changes were performed to determine the optimal grafting time of CNTs and BFs;Complex shear modulus and ductility electrical healing tests of CNTs/BF pastes were designed to analyze the energized healing effect of CNTs/BF pastes;Infrared thermography and digital image scattering deformation monitoring(DIC)were com-bined to analyze the electrical healing behavior of CNTs/BF pastes and reveal their healing mechanism.The results of the study show that:The resistivity of CNTs/BF at 3 h of grafting decreases by 6 orders of magnitude,the element-al mass fractions of C and the Si-O-Si peak area are increased by 23.96％and 60.54％,respectively,compared with the original sample BF,and 3 h is the optimal grafting time.The energized healing test shows that the healing indices of CNTs/BF pastes are higher than those of BF and CNTs pastes,and the complex shear modulus healing indices are improved by 14.7％and 18.6％and the ductility healing indices are improved by 22.43％and 16.76％at 0.3wt％doping compared with BF and CNTs pastes,respectively,and the optimal doping level is 0.3wt％.Infrared thermography shows that the temperature enhancement rates of CNTs/BF pastes are 123.53％and 533.53％higher compared to BF and CNTs pastes,respectively,indicating that CNTs/BF pastes have localized warming characterist-ics.DIC shows that CNTs/BF mastic have a healing height difference of 1.86 mm at the crack,which are 77.99％and 160.14％higher than that of BF and CNTs mastic,respectively,and the crack shows directional healing.Based on this,the energized healing mechanism of CNTs/BF mastic is revealed,and the research results provide an important reference for the application of CNTs/BF in road engineering.
关键词
路面新材料/碳纳米管接枝纤维/接枝工艺/导电沥青胶浆/通电愈合/愈合水平Key words
new pavement materials/CNTs grafted fibers/grafting process/conductive asphalt mastic/ener-gized healing/healing level引用本文复制引用
出版年
2024
NETL
NSTL
万方数据