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类型 综合研究 预答辩日期 2017-11-13
开始(开题)日期 2015-09-06 论文结束日期 2017-09-14
地点 道桥实验室会议室 论文选题来源 省(自治区、直辖市)项目    论文字数 6 (万字)
题目 生物质再生沥青混合料微观特性研究
主题词 生物再生剂,路用性能,再生机理,微观特性
摘要 现阶段,利用可再生的生物材料代替传统石化产品已日益受到社会和科研机构的重视。沥青材料作为石油加工产业的重要产物之一,亦是铺筑高等级公路不可或缺的原材料,对其再生利用具有显著的社会意义和工程价值。目前研究者已对沥青混合料再生技术进行了大量卓有成效的研究,结果表明,再生剂的使用能够极大提升废旧沥青混合料的再生效率。然而传统再生剂通常是石化产业的上游产品,价格高昂,若合理利用生物质材料取代传统再生剂则有望极大降低工程成本,实现真正意义上的可持续发展。基于此,本研究对生物再生剂应用于沥青混合料再生的可行性进行探究,并分析再生混合料的微观特性及其对路用性能的影响,以期全面了解生物再生技术的应用前景。 首先,本文在对比三种代表性生物油源(分别为生物乙醇残渣类沥青、生物柴油残渣类生物油和环氧植物油基生物油)基本性质的基础上,筛选出环氧植物油基生物油作为生物再生剂的基质油料,通过常规试验测试其再生性能(与市售再生剂进行对比),针对再生性能不足之处复配增塑剂以制备生物再生剂,各项常规检测数据表明,经这种生物再生剂再生的老化沥青与基质沥青性能相似。利用制备的生物再生剂对不同长期老化沥青进行再生,采用流变试验测试再生沥青的性能,发现生物再生剂对老化沥青的施工和易性和硬度改善较好,但对抗疲劳性能恢复有限;低温试验表明,这种生物再生剂再生的沥青不适用于极端低温地区。化学试验结果表明,生物再生剂的加入主要是通过降低氧化官能团和沥青质的比例、增加低-中分子量分子的含量来改变老化沥青的性质。 其次,基于微观结构和沥青组分、性能之间关联性分析结果,构建了基于微观结构的再生理论,利用这一理论对生物再生机理进行了分析,发现虽然生物再生剂降低了老化基质沥青的黏度,但是沥青样品内部分子扩散能力却没有得到增强,这与生物再生剂中较高的胶质含量有关;对于老化SBS改性沥青,由于聚合物的存在,分子量相对较小的生物再生剂能够达到增强改性沥青分子流动扩散能力的目的。 然后,将生物再生剂与沥青混合料旧料按不同比例和新集料、新沥青进行混合制备再生沥青混合料,并采用市售再生剂设置对照组进行对比研究。通过车辙试验、低温弯曲试验、冻融试验、四点弯曲试验和动态模量试验对不同再生混合料的路用性能进行测试。试验结果表明,对于再生混合料,添加再生剂比不添加再生剂性能更优,而生物再生剂对旧料的再生能力最优。 最后,采用纳米压痕试验对上述混合料的微观特性进行表征,结果表明生物再生剂对胶浆-过渡区-集料区域的力学性能改变最为显著;蠕变试验结果也表明生物再生剂具有优良的再生效果,能够显著改善沥青胶浆相的黏弹性。微观结果验证了生物再生剂能够有效改善回收沥青混合料路用性能这一结论。
英文题目 Investigation on micro-properties of bio-rejuvenated asphalt mixture
英文主题词 bio-rejuvenator, pavement performance, rejuvenation mechanism, micro property
英文摘要 As the depletion of nonrenewable materials, using renewable bio-materials to replace traditional petroleum-based products has gained great attentions nowadays. Asphalt is a vital raw material in pavement engineering. Great engineering value can be obtained through using reclaimed asphalt concrete. Present researches have shown that using rejuvenator can enhance the efficiency in recycling asphalt pavement. However, most of the rejuvenators used today are derived from crude oils which making it expensive. If bio-materials with a low price are used to replace traditional rejuvenator, the cost of construction will be lowered and sustainable development can be obtained. Thus, this research investigates the feasibility of using bio-rejuvenator in recycling asphalt concrete at both micro and macro scales. Firstly, three typical bio-oils (residue of bio-ethanol production, residue of bio-diesel production and epoxidized vegetable oil based bio-oil) are compared and epoxidized vegetable oil (EVO) based bio-oil is found to be suitable for fabricating bio-rejuvenator. Its rejuvenation efficiency is checked by conventional tests. Based on test results, plasticizer is added to enhance its rejuvenation effect. Conventional tests results show that this fabricated bio-rejuvenator can recover aged asphalt to the level same as virgin asphalt. The rejuvenation effects are further evaluated using rheological tests and chemical methods. It was found the workability of long term aged asphalt is enhanced and stiffness is lowered by adding bio-rejuvenator. The anti-fatigue properties of aged asphalt can be improved but can’t be recovered to the level as virgin asphalt. Low temperature test results indicate that bio-rejuvenated asphalt is not suitable for extreme low temperature region. Chemical tests show that addition of bio-rejuvenator can lower the content of oxidized functional groups and asphaltenes. The contents of low- and intermediate-molecule-weight molecules are increased during bio-rejuvenation. Afterwards, bio-rejuvenation mechanism is proposed based on the analysis on the components-microstructure-performance relationship. It is found that the molecule diffusion ability is not enhanced though the viscosity of bio-rejuvenated asphalt decreases. For aged SBS modified asphalt, bio-rejuvenator can hence the molecule diffusion ability. Then, bio-rejuvenator together with reclaimed asphalt pavement, virgin aggregate and virgin asphalt are used in fabrication of recycled asphalt concrete. One commercial rejuvenator is also used. Wheel rutting test, low temperature bending test, freezing and thawing test, four point bending test and dynamic modulus test are employed to evaluate the pavement performance of recycled asphalt concrete. Bio-rejuvenator shows better rejuvenation effects than commercial rejuvenator. Finally, nanoindentation test is used to characterize the micro properties of recycled asphalt concrete. It is found that bio-rejuvenator can significantly change the mechanical properties of mastic, transition zone and aggregate. Creep test analysis also shows that bio-rejuvenator has better rejuvenation effect than commercial rejuvenator in recycling asphalt mixture and significantly changes the viscoelastic properties of asphalt materials. Micro test result proves that bio-rejuvenator can effectively enhance the pavement performance of recycled asphalt concrete.
学术讨论
主办单位时间地点报告人报告主题
Western research institute 2016年7月 美国黄石 龚明辉 Characterization of aggregate-mastic transition zone’s mechanical properties through nanoindentation test: is this a feasible way to determine blending efficency of RAP mixture
大连理工大学 2015年7月 大连 龚明辉 Research on the property of bio-oil rejuvenated asphalt
东南大学 2016年3月 南京 William S. Wong Functionally Enhanced Microsystems for Flexible Electronics
东南大学 2015年6月 南京 Haddock Modifying Laboratory Mixture Design to Improve Field Compaction
东南大学 2015年3月 南京 Eric Schlangen Self-Healing Concrete and Asphalt
东南大学 2015年5月 南京 Dov Leshchinsky Reinforcement: Applications and Properties
Transportation research board 2016年1月 美国华盛顿 龚明辉 Investigation on adhesion behavior of bio-oil modified asphalt using SDD and AFM
Purdue University 2016年1月 美国西拉法叶 龚明辉 Investigation on pavement performance and modification mechanism of carbon nanotubes modified asphalt
     
学术会议
会议名称时间地点本人报告本人报告题目
ICPT2017 2017年8月 香港 Raman spectroscopy study on asphalts modified through different carbon nanotubes
CEW2016 2016年5月 荷兰 Investigation on the wax-induced phase separation behavior and its impact on asphalt’s rheological properties
东南大学自愈合workshop 2015年 南京 Research on the aging properties of bio-oil rejuvenated asphalt
中国石油大学交流访问 2016年 青岛 基于剥离试验的沥青自愈合研究
     
代表作
论文名称
Characterization of adhesion and healing at the interface between asphalt and aggregate using Atomic
基于原子力显微镜的沥青微观结构研究
Evaluation of bio-binder modified asphalt’s adhesion behavior using sessile drop
Quantitative characterization of asphalt’s composition–microstructure relationship
Physical-chemical properties of aged asphalt rejuvenated by bio-oil derived from
Investigating the performance, chemical, and microstructure properties of carbon
 
答辩委员会组成信息
姓名职称导师类别工作单位是否主席备注
黄晓明 正高 教授 博导 东南大学
肖鹏 正高 教授 博导 扬州大学
黄再兴 正高 教授 博导 南京航空航天大学
赵永利 正高 教授 博导 东南大学
许涛 正高 教授 博导 南京林业大学
      
答辩秘书信息
姓名职称工作单位备注
陈先华 副高 副教授 东南大学