沥青混合料应变-寿命疲劳方程研究

在国内外研究成果基础上,提出了合理可行的沥青混合料直接拉伸疲劳试验中试件尺寸、失效判据、控制方式、加载频率和试验温度等条件.基于不同应变水平的疲劳试验结果,分析了平均应力影响,建立了沥青混合料应变—寿命疲劳方程,可作为疲劳开裂寿命预估的依据,并提出了沥青混合料疲劳开裂拉应变的阀值和极限值.利用沥青混合料直接拉伸疲劳试验得到的应变—寿命疲劳方程能更好体现沥青混合料的疲劳特征,其疲劳开裂拉应变的阀值和极限值能充分反映沥青混合料疲劳破坏的过程.

Research on Equation of Strain -life Fatigue for Asphalt Mixture

Based on the world-wide researches,the reasonable and feasible testing conditions of direct tension for asphalt mixture included specimen dimension,judgment,controlled mode,load frequency and test temperature are determinated. With the fatigue test results by various strain level,equation of strain-life fatigue for asphalt mixture which can be wsed as a rule to forecast fatigue cracked life is put forward after the revision of average stress.The minimum and maximum tension strains of fatigue cracked for asphalt mixture are also advanced.Equation of strain-life fatigue for asphalt mixture based on direct tension tests of asphalt mixture is better to explain the fatigue character of asphalt mixture.The minimum and maximum tension strains of fatigue cracked for asphalt mixture could enough express the proceeding of asphalt mixture fatigue damage.