布敦岩沥青改性沥青混合料疲劳耐久性试验研究

摘要

为了研究布敦岩沥青改性沥青混合料的疲劳耐久性,利用万能材料试验系统,对基质沥青混合料、布敦岩沥青改性沥青混合料和SBS改性沥青混合料进行4种不同应力比条件下的疲劳耐久性试验,分别拟合得到3种沥青混合料的疲劳方程拟合参数,并对试验结果进行对比分析.试验结果表明:在相同应力比条件下,基质沥青混合料疲劳寿命最短,SBS次之,布敦岩沥青改性沥青混合料的疲劳寿命最长;布敦岩沥青改性沥青混合料疲劳方程拟合参数K最大,n最小.疲劳方程拟合参数K和n表征布敦岩沥青改性沥青混合料对于应力比变化的敏感程度最低,在荷载水平增加相同幅度的条件下,布敦岩沥青改性沥青混合料的疲劳寿命衰减量最小,进一步说明其具有较好的抵抗疲劳荷载的能力,其疲劳耐久性最好,将其用于沥青路面铺筑可有效延长路面的使用寿命.%In order to study the fatigue durability of BRA modified asphalt mixture, with the help of universal material testing system, the authors have carried out fatigue durability tests under four kinds of different stress ratios conditions for matrix asphalt mixture, Buton asphalt modified asphalt mixture and SBS modified asphalt mixture, and obtained respectively fitting parameters of the fatigue equation of three kinds of asphalt mixtures. The test results show that under the same stress ratio, the fatigue life of matrix asphalt mixture is the shortest, followed by SBS, and the fatigue life of BRA modified asphalt mixture is the longest. In BRA modified asphalt mixture fatigue equation fitting parameters, the K is the biggest and the n is smallest. Fatigue equation fitting parameters K and n shows BRA modified asphalt mixture has the lowest sensitivity to the change of stress ratio. When the loading level increases by the same amplitude, the fatigue life of BRA modified asphalt mixture attenuates the smallest amount, which further shows that it has better ability to resist fatigue load, the fatigue durability is the best, its application to asphalt pavement can effectively extend the service life of the road.