新疆岩沥青改性沥青混合料疲劳性能的试验研究

为了揭示岩沥青改性沥青混合料的疲劳耐久性,利用MTS-810材料试验系统,分别对普通重交沥青混合料、SBS改性沥青混合料和岩沥青改性沥青混合料等3种混合料进行了不同应力比下的疲劳试验,建立了3种沥青混合料的S-N疲劳方程,并对3种沥青混合料的疲劳试验结果进行了比较.在相同的应力比试验条件下,岩沥青改性沥青混合料的疲劳寿命最大,普通重交沥青混合料的疲劳寿命最小.岩沥青改性沥青混合料S-N疲劳方程参数k最大,n最小.研究结果表明:两个疲劳方程参数k和n均证实了岩沥青改性沥青混合料具有较好的抵抗疲劳荷载的能力.在荷载水平增加相同幅度的情况下,岩沥青改性沥青混合料的疲劳寿命衰减量最小.在相同的级配、油石比和荷载条件下,其疲劳耐久性最好.

Research on fatigue character tests of asphalt mixtures modified by Xinjiang rock asphalt

In order to reveal the fatigue durability of asphalt mixtures modified by rock asphalt,the fatigue tests under different stress ratios were carried out by Material Test System(MTS-810) of ordinary heavy traffic asphalt mixture,asphalt mixture modified by SBS,asphalt mixture modified by rock asphalt.S-N fatigue equations were established of the three kinds of asphalt mixture.The fatigue test results of the three asphalt mixtures were compared.Under the same stress ratio test conditions,the fatigue life of the biggest one is the asphalt mixture modified by rock asphalt,the fatigue life of the minimum one is the ordinary heavy traffic asphalt mixture.The S-N fatigue equation parameter k value is the largest,n value is the minimum one to the asphalt mixture modified by rock asphalt.It indicates that the asphalt mixture modified by rock asphalt has the good ability to resist the action of the fatigue load for the aspect of the two fatigue equation parameters k and n.The attenuation amount of the fatigue life is the minimum one for the asphalt mixture modified by rock asphalt under the same increased amplitude of the load level.With the same of gradation,asphalt-aggregate ratio and the load conditions,its fatigue durability is the best.