泡沫沥青冷再生混合料疲劳特性及其长寿命冷再生沥青路面结构优化  

Fatigue Characteristics of Foamed Asphalt Cold Recycled Mixture and Structural Optimization of Long-life Cold Recycled Asphalt Pavement

作　　者：丛培 凌涛 CONG Pei;LING Tao(China Railway Fifth Bureau Group First Engineering Co.Ltd.,Changsha 410117,China)

机构地区：[1]中铁五局集团第一工程有限责任公司,长沙市410117

出　　处：《公路》2021年第12期8-16,共9页Highway

基　　金：国家自然科学基金资助项目,项目编号51804113。

摘　　要：为了研究新旧沥青长期融合作用下泡沫沥青冷再生混合料的抗疲劳耐久性,采用4点弯曲疲劳试验,对80%、100%的RAP泡沫沥青冷再生混合料进行了低应变水平下的疲劳试验,分析RAP、再生剂、模拟服役时间对泡沫沥青冷再生混合料疲劳性能的影响规律,拟合回归了泡沫沥青冷再生混合料的疲劳方程,确定了泡沫沥青冷再生混合料的疲劳极限应变,进而优化了长寿命泡沫冷再生沥青路面结构。结果表明:添加再生剂对泡沫沥青冷再生混合料的力学性能、路用性能和抗疲劳性能有显著增强作用;增大荷载应变水平显著降低了泡沫沥青冷再生混合料的疲劳寿命,泡沫沥青冷再生混合料疲劳寿命对应变水平变化极为敏感,增大RAP掺量或添加再生剂均能改善冷再生混合料的抗疲劳性能;室内放置期间,泡沫沥青冷再生混合料疲劳寿命同样存在增长过程;将泡沫沥青冷再生混合料中的RAP仅作为黑色集料,低估了泡沫沥青冷再生混合料的抗疲劳性能。推荐泡沫沥青冷再生混合料的疲劳极限应变为100με。在此应变水平下,泡沫沥青冷再生路面满足长寿命沥青路面抗疲劳性能要求。In order to study the anti-fatigue durability of foamed asphalt cold recycled mixture under long-term fusion of new and old asphalt, a four-point bending fatigue test is carried out to perform fatigue under low strain level on 80% and 100% RAP foamed asphalt cold recycled mixture. The influence of RAP, regenerant and simulated service time on the fatigue performance of foamed asphalt cold recycled mixture are analyzed, the fatigue equation of foamed asphalt cold recycled mixture are fitted and regressed, and the fatigue limit strain of foamed asphalt cold recycled mixture is determined, the long-life foam cold recycled asphalt pavement structure is then optimized. The results show that the addition of regenerating agent can significantly enhance the mechanical properties, road performance and fatigue resistance of the foamed asphalt cold recycled mixture. Increase the load strain level can significantly reduce the fatigue life of the foamed asphalt cold recycled mixture. The fatigue life of the foamed asphalt cold recycled mixture is extremely sensitive to changes in the level of change. Both increasing the RAP and adding a regenerating agent can improve the fatigue performance of the cold recycled mixture. During indoor storage, the fatigue life of the foamed asphalt cold recycled mixture also has a growth process. The RAP in the foamed asphalt cold recycled mixture is only used as black aggregate, which underestimates the anti-fatigue performance of the foamed asphalt cold recycled mixture. It is recommended that the fatigue limit strain of the foamed asphalt cold recycled mixture is 100με. At this strain level, the foamed asphalt cold recycled pavement meets the fatigue resistance requirements of the long-life asphalt pavement.

关 键 词：道路工程 泡沫沥青冷再生混合料 再生剂 疲劳特性 长寿命沥青路面 

分 类 号：U416.217[交通运输工程—道路与铁道工程] U416.26