沥青混合料应变疲劳性能的试验研究

沥青混合料疲劳试验的荷载控制模式有应力控制模式和应变控制模式。而在应变控制的疲劳试验过程中 ,沥青混合料的应力应变状态更符合沥青路面的实际情况。试验得出的弯拉应变与疲劳寿命之间的关系便于应用。运用 MTS81 0材料试验系统 ,进行了 5种级配的沥青混合料的应变控制模式的疲劳试验 ,得出了它们的应变疲劳方程 ,并对疲劳方程进行了比较和分析。研究表明 ,同一应变 (或应变比 )下 ,若干试件的对数疲劳寿命表现为正态分布 ,而且应变、应变比与疲劳寿命分别在双、单对数坐标上表现为直线关系 ;单对数坐标下以应变比表示的疲劳方程较双对数坐标下的以应变表示的疲劳方程稳定 ,而双对数坐标下的疲劳方程更易区分出沥青混合料疲劳性能的优劣 ;应变控制模式下的疲劳试验 ,其它条件相同时 ,沥青混合料的模量越小 ,疲劳寿命越长。

Study on asphalt mixtures fatigue properties by testing

There are two kinds of load controlling mode for asphalt mixtures fatigue testing:stress controlling mode and strain controlling mode.However,the latter is more practical.Firstly,five kinds of asphalt mixtures were experimented with the fatigue testing of control strain mode using MTS810.By the experiment,a fatigue function between fatigue life span and the value of repeated strain as the ratio of strain level was set up.In addition,their fatigue properties were analyzed.It is shown that at the same strain level,asphalt mixtrues logarithm fatigue life is normal school,meanwhile,relation of strain level with logarithm fatigue life is linear.In the fatigue testing of control strain mode,when asphalt mixtrues modulus is much lower,its fatigue life is much longer.