摘要
为科学评价沥青混合料的自愈性能,开发基于高压渗水的密级配沥青混合料自愈性能的测试装置,提出评价指标,通过试验确定愈合时间、愈合温度与最小样本数等关键参数。通过测试不同愈合温度与时间、混合料类型与微胶囊掺量下的密级配沥青混合料的渗水速率比(v_e),验证该方法的敏感性与稳定性。对比分析v_e与间歇式疲劳寿命及劈裂愈合强度比(SHSR),论证该方法的有效性。结果表明:该方法的适宜试验参数为愈合时间12 h,愈合温度45℃,制缝温度5℃±2℃,最小样本数n=4;该方法能有效区分测试条件(愈合温度与时间)、混合料类型及最大公称粒径、微胶囊掺量对自愈性的影响,平行试验结果的变异系数在3.0%,满足敏感性及稳定性要求;v_e与间歇式疲劳寿命及SHSR在评价密级配沥青混合料自愈性方面具有一致性,且具有试验设备简单,结果稳定等优点;在一定范围内,沥青混合料裂缝自愈效果随微胶囊掺量的增加和温度的升高而提高,且自愈性能随愈合时间的延长呈非线性增长;公称最大粒径越小,自愈效果越好,悬浮密实级配AC的自愈性能优于骨架密实级配SMA。
A test device was developed to evaluate the self-healing property of dense-graded asphalt mixtures,and the evaluation index was proposed accordingly.The key test parameters, which were determined by indoor experiments,included the healing time,healing temperature, and minimum number of samples.The sensitivity and stability of the developed method were verified by testing the seepage rate ratios (νe)of dense-graded asphalt mixtures for different healing temperatures and times,mixture types,and microcapsule contents.The νe results were compared with the traditional intermittent fatigue lives and splitting healing strength ratios (SHSRs)to demonstrate the effectiveness of the proposed method.The results show that the appropriate parameters are as follows,healing time is 12h,healing temperature is 45℃, temperature for creating cracks is 5℃±2℃,and minimum s.ample number is four.The proposed method can effectively distinguish amongst the effects of test conditions (healing temperature and time),types of mixtures and nominal maximum particle sizes,and microcapsule content on the self-healing property of the specimens the variation was within 3% when .the tests were repeated,which proves that the present method meets the requirements of sensitivity and stability.The νe is consistent with the intermittent fatigue life and SHSR in evaluating the self- healing property of the dense-graded asphalt mixture;the main advantages of the proposed method are simple equipment,stable results.Within a certain range,the self-healing effect increases with the microcapsule content and temperature.The self-healing effect shows a non- linear trend with healing time.For smaller nominal maximum particle sizes,the self-healing effects are better.The self-healing effect of the suspended compact gradation (AC)is better than that of the skeleton compact gradation (SMA).
作者
纪小平
杨自广
周泽洪
张宜洛
雷雨滋
JI Xiao-ping;YANG Zi-guang;ZHOU Ze-hong;ZHANG Yi-luo;LEI Yu-zi(Key Laboratory of Road Structure &Materials of Ministry of Transport,Chang'an University,Xi'an 710064,Shaanxi,China;Liaoning Expressway Operation and Management Co.,Ltd,Shenyang 110003,Liaoning,China;Siehuan Communication Survey &Design Institute,Chengdu 610017,Sichuan,China)
出处
《中国公路学报》
EI
CAS
CSCD
北大核心
2018年第11期51-57,共7页
China Journal of Highway and Transport
基金
国家自然科学基金项目(51408044)
陕西省自然科学基础计划项目(2017JM5034)
中央高校基本科研业务费专项资金项目(310821172008
310821171018)
关键词
道路工程
沥青混合料
高压渗水试验
自愈性能
间歇式疲劳寿命
劈裂愈合强度比
road engineering
asphalt mixture
high pressure seepage test
self-healing property
intermittent fatigue life
Splitting healing strength ratio
