摘要
微胶囊沥青混合料具有一定的裂缝自愈能力,可延长沥青路面使用寿命,其研究已逐步引起重视。采用高压渗水试验评价微胶囊沥青混合料的自愈性能,研究微胶囊掺量、混合料属性(公称最大粒径、空隙率、沥青种类和用量)与使用环境(温度、时间及水分)对自愈性能的影响规律,考察微胶囊掺量对混合料路用性能的影响。结果表明,沥青混合料自愈性能随微胶囊掺量的增加先提高后降低,最佳微胶囊掺量为6%;随着公称最大粒径与空隙率的增加,混合料自愈性能逐渐变差;基质沥青混合料的自愈性能优于改性沥青,且油石比越大自愈性能越好。在一定范围内温度越高、自愈性能越好,自愈性能随愈合时间的延长呈非线性增长,水分对沥青混合料自愈有着不利的影响。随着微胶囊的增加,混合料中的矿料摩阻力与矿料/沥青黏附性降低,导致沥青混合料的高温稳定性与水稳定性有所降低;掺入微胶囊后,沥青混合料的裂缝自愈能力得到增强,因此反映抗裂性能的低温弯曲破坏应变得到一定程度的改善。综合混合料自愈性能与路用性能随微胶囊掺量的变化规律,推荐微胶囊掺量为4%~6%。
Asphalt mixture with microcapsule has a certain crack self-healing capability,which can extend the service life of asphalt pavement.Its application and research have gradually attracted attentions.In this paper,the self-healing effect of microcapsule asphalt mixture is evaluated by high pressure seepage test.The influence of microcapsule content,mixtures type and parameters(maximum nominal particle size,air void,asphalt type and amount)and environment(self-healing temperature,selfhealing time and moisture)on the self-healing effect and the influence of microcapsule content on the pavement performance of the mixture are studied.The results show that the crack self-healing effect is proportional to the content of microcapsules in a proper range,and the optimum content of microcapsules is 6%.The self-healing effect of suspension compact framework(AC type)is better than that of skeleton compact framework(SMA type).The smaller the nominal maximum particle size,the better the selfhealing effect,and the smaller the void fraction,the more obvious the self-healing effect.Matrix asphalt is superior to modified asphalt,and the bigger the asphalt-stone ratio,the better the self-healing effect of cracks;in a certain range,the higher the temperature,the better the self-healing effect of cracks.The self-healing effect of cracks increases nonlinearly with the extension of healing time,and moisture has a negative impact on the self-healing effect of microcapsule asphalt mixture cracks.With the increase of microcapsule content,the high temperature stability of asphalt mixture decreases,the low temperature crack resistance gradually strengthens,and the water stability weakens.The recommended microcapsule content is 4%to 6%,according to the self-healing properties and road performance vary with the amount of microcapsules.
作者
周泽洪
杨自广
纪小平
李杰
冯太群
ZHOU Ze-hong;YANG Zi-guang;JI Xiao-ping;LI Jie;FENG Tai-qun(Sichuan Communication Surveying and Design Institute Co.Ltd.,Chengdu,610017,China;Liaoning Expressway Operation and Management Co.Ltd,Shenyang 110003,China;School of Highway,Chang’an University,Xi’an 710064,China)
出处
《公路》
北大核心
2021年第2期45-51,共7页
Highway
基金
国家自然科学基金资助项目,项目编号51408044
四川省交通运输科技项目,项目编号2017-B-09。
关键词
道路工程
微胶囊
沥青混合料
自愈性能
路用性能
road engineering
microcapsule
asphalt mixture
self-healing property
road performance
