摘要
乳化沥青冷再生混合料的抗疲劳开裂性能会影响沥青路面结构层整体服役寿命。为了评价不同增强方式下乳化沥青冷再生沥青混合料的疲劳性能,以普通乳化沥青、外掺玄武岩纤维和SBR改性乳化沥青这3种冷再生混合料为研究对象,开展了乳化沥青冷再生混合料中梁试件的四点弯曲疲劳试验,建立了3种乳化沥青冷再生沥青混合料的疲劳方程,揭示了疲劳过程中动态弯拉模量和累积耗散能的演化规律。采用扫描电镜试验获取了乳化沥青冷再生混合料疲劳破坏界面的微观形貌。试验结果表明:动态弯拉模量衰减至初始模量的70%~80%即可能发生断裂。动态弯曲劲度模量比κ越小、累积耗散能越大,疲劳性能越好。SBR改性乳化沥青和外掺玄武岩纤维均可以改善乳化沥青冷再生混合料的抗疲劳性能。SEM试验揭示了乳化沥青冷再生混合料的抗疲劳性能增强机理。研究成果可为乳化沥青冷再生混合料的抗疲劳性能提升及其耐久性设计提供参考。
The anti-fatigue cracking performance of emulsified asphalt cold recycled mixture will affect the overall service life of the structural layer.The objective of this study is to evaluate the fatigue performance of emulsified asphalt cold recycled mixture under different reinforcement methods.The four-point bending fatigue test of the beam was carried out on three kinds of cold recycled mixtures,including ordinary emulsified asphalt,basalt fiber and styrene-butadiene rubber(SBR)modified emulsified asphalt.The fatigue equations of three kinds of emulsified asphalt cold recycled asphalt mixtures were established,and the evolution law of dynamic flexural modulus and cumulative dissipation energy during fatigue process was revealed.Scanning electron microscope(SEM)test was used to analyze the micro morphology of fatigue failure interface of emulsion asphalt cold recycled mixture.The test results show that fracture may occur when the dynamic bending tensile modulus decreases to 70%to 80%of the initial modulus.The smaller the dynamic modulus ratioκ,the greater the cumulative dissipated energy,the better the fatigue performance.SBR modified emulsified asphalt and basalt fiber can improve the anti-fatigue performance of emulsified asphalt cold recycled mixture.The mechanism of anti-fatigue performance enhancement of emulsified asphalt cold recycled mixture under fiber reinforcement is revealed by the SEM test.The research results can provide reference for the improvement of fatigue resistance and durability design of emulsified asphalt cold recycled mixture.
作者
周琛
褚晨枫
丁亮
王子昂
况澳
刘宏富
ZHOU Chen;CHU Chenfeng;DING Liang;WANG Zi’ang;KUANG Ao;LIU Hongfu(Wuhan Comprehensive Transportation Research Institute Co.,Ltd.,Wuhan,Hubei 430015,China;School of Traffic&Transportation Engineering,Changsha University of Science&Technology,Changsha,Hunan 410114,China)
出处
《公路工程》
2024年第2期116-123,157,共9页
Highway Engineering
基金
国家自然科学基金资助项目(52078064)。
关键词
道路工程
乳化沥青冷再生混合料
四点弯曲疲劳试验
玄武岩纤维
疲劳性能
增强机理
road engineering
emulsified asphalt cold recycled mixture
four-point bending fatigue test
basalt fiber
fatigue performance
enhancement mechanism
作者简介
周琛(1980-),男,湖北武汉人,高级工程师,研究方向:道路工程设计;通信作者:刘宏富,E-mail:lhf 0625@csust.edu.cn。
