Bonifiber纤维对沥青混合料抗疲劳性能的影响

Effect of Bonifiber Fiber on Fatigue Resistance Property of Asphalt Mixture

本文采用MTS-810材料测试系统,对AC-20及SMA-13两种沥青混合料进行疲劳测试,标本总共96份,分别采用0.3 MPa、0.4 MPa、0.5 MPa、0.6 MPa、0.8 MPa、1.0 MPa、1.2 MPa、1.6 MPa的常应力、三分点加载,对AC-20、AC-20+0.2%Bonifiber与SMA-13、SMA-13+0.1%Bonifiber分别做疲劳试验对比,每组24份样本,每种常应力下做3份样本,由实验结果可知,加入Bonifiber纤维的沥青混合料强度和刚度明显提高,拟合四组疲劳试验结果,得到的线性回归。尤其对SMA-13,抗弯刚度增长了142%,极限荷载提高了38%。在允许应力范围内,掺入Bonifiber纤维的AC-20,随应力的增长疲劳寿命的变化率也在增长。掺入Bonifiber纤维的SMA-13,随应力的增长疲劳寿命变化率反而在减小。

In this test, Bonifiber fiber is mixed into asphalt mixture to improve its anti-fatigue properties. MTS-810 Material Test System is used for fatigue tests of asphalt mixture of AC-20 and SMA-13. With the use of 96 samples in total, constant stress of 0.3 MPa, 0.4 MPa, 0.5 MPa, 0.6 MPa, 0.8 MPa, 1.0 MPa, 1.2 MPa, 1.6 MPa are respectively used by third-point loading to undertake fatigue comparison test on AC-20, AC-20 ＋0.2% Bonifiber, SMA-13 and SMA-13 ＋0.1% Bonifiber, each set consisting of 96 samples, among which 3 samples are used for test under each kind of constant stress. According to the experimental results, adding Bonifiber fiber into asphalt mixture can significantly improve its strength and stiffness and get the linear regression by the use of fitting of four sets of fatigue test results. In particular, flexible stiffness of SMA-13 increased 142 percent and ultimate load has a increase of 38 percent. Within the range of allowable stress, for AC-20 for AC-20 which has added Bonifiber, the rate of change of fatigue life rises with the increase of stress. However, for SMA-13 which has added Bonifiber fiber, the rate of change of fatigue life reduces with the increase of stress. It is expected that the test can provide a reference for fatigue failure of asphalt mixture on high-speed heavy-loaded road in the future.