摘要
为研究拌合工艺对再生剂与新老沥青扩散融合行为的影响,实现回收沥青路面材料(RAP)的有效利用,分别对采用4种工艺[RAP预热+温拌剂(HW工艺)、RAP预热(H工艺)、RAP冷加+温拌剂(CW工艺)、RAP冷加(C工艺)]制备的再生沥青混合料进行分层浸渍,提取出混合料内外层沥青试样,并利用凝胶渗透色谱(GPC)和原子力显微镜(AFM)进行测试分析。GPC归一化分子量曲线及不同区域面积积分分析表明:C工艺试样内外层曲线差异最大(外层小分子含量33.1%,内层大分子含量26.3%),HW工艺试样内外层曲线最接近(外层小分子含量25.7%,内层大分子含量21.3%),H工艺与CW工艺试样介于两者之间。AFM三维形貌显示:C工艺与HW工艺沥青试样较老化沥青呈现更密集的细长平滑小凸起,HW工艺呈现的凸起较C工艺更均匀。再生剂与新老沥青扩散融合过程不均匀,不同工艺下扩散融合效果由强到弱依次为HW、H、CW、C,RAP预热并添加温拌剂(HW工艺)最有利于促进再生剂的有效扩散融合。
To investigate the influence of mixing processes on the diffusion and fusion behavior between rejuvenator and aged/virgin asphalt,thereby promoting effective utilization of reclaimed asphalt pavement(RAP),recycled asphalt mixtures prepared using four processes(RAP preheating+warm-mix additive(HW process),RAP preheating(H process),RAP cold addition+warm-mix additive(CW process),RAP cold addition(C process))were subjected to layered extraction.Asphalt samples from the inner and outer layers of the mixture were obtained and analyzed using gel permeation chromatography(GPC)and atomic force microscopy(AFM).Analysis of GPC-normalized molecular weight curve and area integration of different regions revealed that the C process samples exhibited the most significant difference between the inner and outer layer curves(outer layer small-molecule content:33.1%;inner layer large-molecule content:26.3%),whereas the HW process samples showed the smallest difference(outer layer small-molecule content:25.7%;inner layer large-molecule content:21.3%).The H process and CW process samples showed intermediate results.AFM three-dimensional topography showed that both the C and HW process asphalt samples displayed denser,elongated,and smooth small bumps compared to the aged asphalt,with the bumps in the HW process samples more uniform than those in the C process samples.The results demonstrated that the fusion and diffusion process between the rejuvenator and the aged/virgin asphalt is not uniform.The effectiveness of diffusion and fusion under the different processes,ranked from strongest to weakest,is as follows:HW,H,CW,C.The process involving RAP preheating combined with warm-mix additive(HW process)is most conducive to promoting effective diffusion and fusion of the rejuvenator.
作者
沈凡
钟亚聃
向天翔
谯理格
SHEN Fan;ZHONG Yadan;XIANG Tianxiang;QIAO Lige(School of Materials Science and Engineering,Wuhan Institute of Technology,Wuhan 430205,China;China Construction Commercial Concrete Jiangxi Co.,Ltd,Nanchang 330006,China)
出处
《武汉工程大学学报》
2025年第6期629-633,652,共6页
Journal of Wuhan Institute of Technology
基金
国家自然科学基金(52178248)
武汉市市政建设集团有限公司科技计划项目(wszky202109)。
关键词
道路工程
再生沥青混合料
分层萃取法
再生剂
扩散融合
road engineering
recycled asphalt mixture
hierarchical extraction
regenerator
diffusion and fusion
