再生路面用聚氨酯改性沥青改性机理与路用性能  

Modification Mechanism and Road Performance of Polyurethane-modified Bitumen for Reclaimed Pavement

作　　者：洪斌 王建翎 李添帅 张宾 谭深 刘文俊 刘峻甫 王大为 HONG Bin;WANG Jian-ling;LI Tian-shuai;ZHANG Bin;TAN Shen;LIU Wen-jun;LIU Jun-fu;WANG Da-wei(School of Transportation of Science and Engineering,Harbin Institute of Technology,Harbin 150090,Heilongjiang,China;School of Civil and Transportation Engineering,Hebei University of Technology,Tianjin 300401,China)

机构地区：[1]哈尔滨工业大学交通科学与工程学院,黑龙江哈尔滨150090 [2]河北工业大学土木与交通学院,天津300401

出　　处：《中国公路学报》2023年第12期275-288,共14页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(52250610218);博士后创新人才支持计划项目(BX20180088);黑龙江省博士后资助项目(LBH-Z18083)。

摘　　要：为促进废旧沥青混合料(RAP)的大规模回收利用,延长老旧沥青路面的使用寿命,以聚氨酯预聚体(PUP)体系(包含扩链剂等助剂)为沥青改性剂,制备高性能的聚氨酯改性沥青(PUMB),并配制出100%RAP掺量的再生混合料,旨在利用力学性质优异、延展性高的聚合物黏结材料,实现老旧沥青路面的就地再生。从分子交互作用、微观性质和力学性能等角度入手,揭示了PUP体系改性剂对沥青的化学改性机制,深入研究了不同改性剂用量下沥青各组分与改性剂间的相互作用规律,并对聚氨酯改性沥青的基本性能及其再生沥青混合料的路用性能进行了评价。结果表明:化学改性过程中PUP主要与扩链剂发生交联反应,少部分PUP与沥青中的沥青质组分反应,共同促使改性沥青体系中PUP的交联程度超过80%;55%质量分数的PUP加入沥青体系时,PUP与沥青各组分的相容性最优,改性沥青形成了最稳定的交联结构体系;与基质沥青相比,PUMB的温度敏感性显著降低,PUP体系显著提升了沥青的高温抗变形能力、低温抗裂性能和抗热氧老化性能,PUMB再生沥青混合料能够服役于交通量大、季节温差大或寒冷地区。与传统老旧沥青路面热再生技术相比,PUMB再生沥青路面能够有效降低拌和温度,大幅度促进资源节约与循环利用,在提升路面养护质量、提高道路养护效能方面具有显著优势。To promote large-scale recycling of reclaimed asphalt pavement(RAP)and prolong the service life of asphalt pavements,a polyurethane prepolymer(PUP)system that includes a chain extender and other additives was used as the modifier to prepare a high-performance polyurethane-modified bitumen(PUMB).PUMB was then used to fabricate a recycled asphalt mixture containing 100%RAP,aiming to achieve the in-situ recycling of pavement using polymer bonding materials with superior mechanical properties and resilience.From the perspectives of molecular interactions,microscopic properties,and mechanical performance,the chemical modification mechanism of bitumen using the PUP system modifier was revealed,and the interactions between four fractions of bitumen and the modifier with different PUP content were studied in depth.The fundamental properties of PUMB and the performance of the recycled asphalt mixture were also evaluated.Results showed that PUP mainly crosslinked with the chain extender and few PUPs reacted with asphaltene components in bitumen in the chemical modification process,which jointly contributed to the level of crosslinking of PUP in PUMB of over 80%.When 55%PUP was added to the asphalt system,the optimal compatibility for the four fractions of bitumen with PUP was achieved,and the crosslinking structure system formed by modified bitumen was the most stable.In contrast to the virgin bitumen,the temperature-sensitivity of PUMB was significantly reduced,and the addition of the PUP system significantly improved the high-temperature deformation resistance,low-temperature crack resistance,and thermal-oxidative aging resistance of bitumen.The recycled asphalt pavement using PUMB as the binder has a potential use in regions with high traffic volumes,large seasonal temperature differences,or low temperatures.Compared with the conventional old asphalt pavement hot recycling technology,the recycled asphalt pavement with PUMB can lower the blending temperature,significantly promoting resource conservation and recycling.Thi

关 键 词：路面工程 聚氨酯改性沥青 分子动力学模拟 作用机理 材料性能 再生沥青路面 

分 类 号：U414[交通运输工程—道路与铁道工程]