| 摘要: |
| 以疲劳过程中沥青黏弹本构模型参数的变化分析沥青的疲劳机理.首先，结合常规疲劳损伤试验和频率扫描试验设计了循环频率扫描疲劳试验，并采用该试验测试分析了2种基质沥青在应变控制模式下的疲劳损伤演化规律；其次，建立了沥青损伤过程中黏弹参数主曲线簇变化规律，结合广义Kelvin Voigt模型分析了沥青黏弹模型特征参数的变化规律；最后，基于敏感性分析，提出沥青疲劳损伤变量指标，并以此阐述了沥青疲劳损伤演化规律.研究发现：沥青疲劳损伤过程中，随着归一化模量值的降低，沥青黏弹参数主曲线簇均向纵坐标轴反方向移动，且其移动间距不断变化，相位角主曲线簇在高频范围内逐渐偏离低频范围时的线性趋势，复数模量相位角主曲线簇曲线长度呈现两端先缩短后增长的趋势，沥青损耗模量储存模量主曲线簇长度不断缩短；广义Kelvin Voigt模型特征参数中仅E2，E3，E4和η0这4个参数存在2个明显的变化阶段.基于参数敏感性分析，提出以参数(E2+E3)/2作为沥青疲劳损伤变量，并验证了疲劳损伤变量变化规律与沥青疲劳裂纹扩展机制的相关性. |
| 关键词: 沥青 循环频率扫描疲劳试验 疲劳损伤变量 疲劳损伤演化规律 |
| DOI：103969/j.issn.1007 9629201903012 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目（51478153，51778195）；石河子大学科研项目(ZZZC201710B) |
|
| Analysis of Asphalt Fatigue Evolution Based on Viscoelastic Characteristics |
|
TIAN Shuang1, SHAN Liyan2, XU Yanan3
|
|
1.College of Water and Architectural Engineering, Shihezi University, Shihezi 832003, China;2.School of Transportation Science and Engineering, Harbin Institute of Technology, Harbin 150090, China;3.College of Civil and Architectural Engineering, North China University of Science and Technology, Tangshan 063000, China
|
| Abstract: |
| The fatigue mechanism of asphalt by the change of the parameters of the asphalt viscoelastic constitutive model during the fatigue process was analyzed. First, a cyclic frequency scanning fatigue test was designed in combination with the conventional fatigue test and the frequency scanning test. Based on the tests， the fatigue evolution of two asphalt under strain control mode was analyzed. Then, the fatigue evolution of master curves in viscoelastic parameters during asphalt damage process was established. And the change rules of the characteristic parameters representing the state of asphalt structure were analyzed based on generalized Kelvin Voigt model. Finally, based on sensitivity analysis, the fatigue damage variable of asphalt was put forward, and the fatigue evolution of asphalt fatigue was expounded. The results show that the asphalt master curves of viscoelastic parameters are all moving in negative direction at longitudinal axis in the process of asphalt fatigue with the mobile space changing. The phase angle versus frequency master curves gradually deviate from linear trend of the low frequency range in high frequency range. The length of the complex modulus versus phase angle master curves shows the trend of shortening first and then increasing. And the length of the loss modulus versus storage modulus master curves is shortened continuously. There are two obvious changes in the characteristic parameters of the generalized Kelvin Voigt model with only E2, E3, E4 and η0. The parameter (E2+E3)/2 is chosen as the fatigue variable of asphalt. It is verified that the variation rule of fatigue variable is related to the mechanism of asphalt fatigue crack propagation. |
| Key words: asphalt cyclic frequency scanning fatigue test fatigue damage variable fatigue damage evolution |
