【作者】 叶青；

【导师】 谭忆秋；

【作者基本信息】 哈尔滨工业大学 ， 交通运输工程（专业学位）， 2016， 硕士

【摘要】 疲劳破坏是沥青混凝土路面损坏的主要形式,因此各国在设计沥青路面时都将疲劳开裂作为重要的控制性指标。研究人员为了更好的评价沥青混合料的疲劳性能,已研究开发了诸多试验方法。沥青混合料具有明显的粘弹性,材料本身的粘弹性质是会影响其疲劳性能的。而现有的研究结论并没有考虑材料属性的影响,无法从本质上揭示沥青混合料抗疲劳性能的优劣,存在一定的缺陷以及局限性。为此,挖掘材料本身粘弹特性对疲劳性能影响,从本质上找出影响材料疲劳失效的原因是十分必要的。针对上述问题,首先从对沥青混合料粘弹性贡献最大的胶浆出发进行研究。利用动态剪切流变仪DSR,对11种不同粉胶比和不同种类沥青制备得的沥青胶浆进行研究。先进行频率扫描试验,得到材料复数模量等无损粘弹参数,通过比较参数值的变化规律,分析材料粘弹性变化。建立主曲线,更加细致的研究粘弹性变化规律。以此为依据,再采用线性幅度扫描试验(LAS)获取沥青胶浆的累积损伤,基于粘弹性连续损伤模型VECD得到相应的损伤曲线并拟合,根据损伤特性对不同沥青胶浆的疲劳性能进行比较,确定不同胶浆的疲劳性能,为后文其对混合料影响的研究提供基础。研究了沥青混合料在静态荷载下的粘弹特性,结合Burgers模型建立静态本构方程,分析了材料瞬时弹性模量、粘弹比例系数等随材料配比、沥青用量、沥青种类不同的变化规律;又研究了动态荷载作用下沥青混合料的粘弹特性:通过动态模量试验,利用分析软件数学计算方法进行模型拟合,确定出动态模量、储存模量、相位角主曲线,对比分析可以表征沥青混合料的粘弹性的指标。最后,对不同沥青用量、不同沥青种类、不同矿料级配的沥青混合料进行劈裂疲劳试验,得到不同应力比下的疲劳寿命。在上述分析的基础上,结合提出的表征材料粘弹性的指标,明确材料固有属性对沥青混合料疲劳性能的作用,通过灰熵分析确定与混合料疲劳性能直接相关并可评价疲劳性能的材料粘弹性参数,确定粘弹性对疲劳性能的影响规律。本文探讨了沥青混合料粘弹属性对疲劳性能的影响,为沥青混合料疲劳性能的研究展示了新的思路和新的依据,为后续沥青混合料的设计提供很好的推动和借鉴作用。更多还原

【Abstract】 Fatigue cracking is the main pavement distress in the field. Fatigue is a very important control index, and a lot of countries use this index to design the asphalt pavement. Many kinds of fatigue tests have been developed to evaluate the fatigue performance of asphalt mixtures by scholars. As the viscoelasticity is a character of asphalt, the character will influences the property of fatigue. But few studies were focused on the the property of asphalt material, so the evaluation method couldn’t reveal the essentials of the mixture fatigue performance. All the evaluation methods have some limitations and imperfections. So explore the influence of the viscoelasticity character to the mixture fatigue performance and the reason of failure of mixture is very necessary.To solve this problem, the paper studied mortar which makes the most contribution to the mixture viscoelasticity firstly. With the utilization of dynamic shear rheometer(DSR), the paper researched 11 kinds of mortars which includes different ratio of filler bitumen and different bitumen types. At first, the researcher used frequency sweeping test to get the index of viscoelasticity. Through comparing the size of viscoelastic parameters to analyze the viscoelastic law and got the master curve to get further viscoelasticity analysis. On this basis, the paper got the accumulated damage of asphalt mortar by linear amplitude sweeping test. The C-S curve is fitted with viscoelastic continuum damage model(VECD), and the fatigue property of different material are carried out based on these model parameters.Then the paper studied the static viscoelastic of asphalt mixtures. Trough the Burgers constitutive model, research analyzed the different mix grading 、 asphalt content、asphalt type effect on instaneous elastic modulus and viscoelastic proportion coefficient. The paper also studied asphalt mixtures viscoelastic under dynamic load. Dynamic modulus test was carried out with mathematical method for fitting. The index which can characterize the mix viscoelastic was got based on the analyze of the master curve of complex modulus、phase angel and storage modulus.Finally, the paper evaluate the fatigue performance of asphalt mixture with different amount and types of asphalt and different gradation. With the basic of the analysis above, the paper confirmed the influence of asphalt property to the fatigue performance utilized viscoelasticity parameter. By analysis the index of viscoelasticity which is related to the fatigue performance of mixture directly, the paper confirmed the viscoelastic range of the best fatigue performance.The paper researched how the asphalt mixture viscoelasticity influence the fatigue performance. The research result provided a new method and basic to asphalt mixture fatigue performance and asphalt mixture design.更多还原