紫外老化对沥青及沥青混合料高低温性能的影响

Effect of ultraviolet aging on high and low temperature performance of asphalt and asphalt mixture

为研究紫外老化对沥青及沥青混合料的高低温性能的影响,开展了沥青及沥青混合料的紫外老化试验。结果显示:在低温性能方面,紫外老化后,沥青的劲度增大,蠕变速率减小,并且在初始阶段增加较为明显;沥青混合料的低温弯曲试验结果显示,紫外老化对小梁的弯拉应变影响较小;在高温性能方面,DSR试验结果显示,紫外老化后沥青的粘弹性组分比例发生了变化,当温度较低时,复数模量会随着频率的增加先增大后减小,当温度较高时,复数模量会随着频率的增加呈线性增大。沥青混合料在紫外老化后其动稳定度有所增加,车辙深度逐渐减小。

In order to study the effect of ultraviolet aging on the high and low temperature performance of asphalt and asphalt mixture, the ultraviolet aging test has been carried out. The results show that：at low temperature performance,the stiffness of asphalt increases and creep rate decreases after ultraviolet aging,which is more obvious at the initial stage of reaction. Results of bending test at low temperature show that UV aging has little effect on the anti-cracking performance of asphalt mixture. The re- suits of DSR test show that the ratio of viscoelastic eomponents of asphalt has changed after UV aging, and complex modulus of high temperature has certain relation with temperature at low temperature,they increase linearly with frequency at first and then decreases,while at high temperature,they increase linearly with frequeney. The dynamic stability of asphalt mixture after UV aging is increased,and the rutting depth decreases gradually.