摘要
沥青混合料回收料(reclaimed asphalt pavement,RAP)的热再生利用可实现道路固废资源化利用,符合绿色可持续发展要求,但高掺量RAP热再生沥青混合料的使用耐久性是急需解决的难题。针对中国南方高温多雨气候特点,开展30%RAP掺量热再生沥青混合料与普通沥青混合料长期高温浸水后的强度衰减、耐疲劳特性与自愈合性能的研究。试验结果表明30%RAP热再生沥青混合料间接拉伸强度和疲劳寿命大于普通沥青混合料,但60℃浸水间接拉伸强度和疲劳寿命均呈明显下降,且强度与疲劳寿命残留率呈明显的线性相关性,可用于强度与寿命预测。普通沥青混合料的间接拉伸疲劳愈合水平高于30%RAP热再生沥青混合料,但浸水后二者自愈合能力大体相当。与间接拉伸疲劳试验相反,30%RAP热再生沥青混合料弯曲疲劳寿命约为普通沥青混合料的50%,60℃浸水14 d后衰减到1/3。二者疲劳愈合性能基本相当,且在有水条件下均难以很好愈合。建立了基于浸水时间的动态模量衰减预测模型,可用于量化分析高温多雨气候条件对模量的影响以及进行剩余疲劳寿命预估。
The hot-recycling of RAP(reclaimed asphalt pavement) can realize the resource utilization of road solid waste,and meet the requirements of green and sustainable development.However,the durability of hot recycled asphalt mixture with high content RAP is an urgent problem to be solved.According to the megathermal and humid climate characteristic,the strength reduction,fatigue characteristic and self-healing performance after long-term water immersion were investigated for hot recycled asphalt mixture contained 30%RAP as well as for conventional asphalt mixture without RAP.Test results indicate that hot recycled asphalt mixture contained 30%RAP has higher indirect tensile strength and fatigue life compared with conventional asphalt mixture.After 60 ℃ water immersion,the strength and fatigue life is obviously declined.The residual percentage of strength and fatigue life shows a linear relation,which allows for the strength to fatigue life prediction.The conventional asphalt mixture has a higher healing level compared with hot recycled asphalt mixture contained 30%RAP.However,this difference of self-healing capacity is found to be limited after water immersion.On the contrary,during four-point bending fatigue test,hot recycled asphalt mixture contained 30%RAP only has about half of the bending fatigue life of conventional asphalt mixture.After 14 days of 60 ℃ water immersion,the bending fatigue life of the former is further reduced to one third of fatigue life of the latter.Both types of mixture have a considerable healing performance,while the fatigue damage is difficult to heal when the specimens were kept in water.The prediction model of modulus reduction over water immersion time is developed to quantitatively evaluate on the effect of megathermal and humid climate on the modulus reduction.Furthermore,this model could also be used to predict the residual fatigue life of hot recycled asphalt mixture.
作者
王雨露
磨炼同
曲良辰
李想
肖月
林俊涛
WANG Yu-lu;MO Lian-tong;QU Liang-chen;LI Xiang;XIAO Yue;LIN Jun-tao(State Key Laboratory of Silicate Materials for Architectures,Wuhan University of Technology,Wuhan 430070,China;School of Materials Science and Engineering,Chang’an University,Xi'an 710061,China;Faculty of Engineering,China University of Geosciences(Wuhan),Wuhan 430074,China)
出处
《科学技术与工程》
北大核心
2024年第26期11409-11422,共14页
Science Technology and Engineering
基金
国家自然科学基金(52278285)。
关键词
热再生沥青混合料
高温浸水
强度衰减
疲劳性能
hot recycled asphalt mixture
high-temperature water immersion
strength reduction
fatigue performance
作者简介
第一作者:王雨露(1997-),男,汉族,河南焦作人,硕士研究生。研究方向:道路材料与工程。E-mail:317577@whut.edu.cn;通信作者:磨炼同(1979-),男,壮族,广西南宁人,博士,副研究员。研究方向:生态建筑材料。E-mail:molt@whut.edu.cn。
