短期老化沥青混合料的低温抗裂性能

Study on Low-Temperature Crack Resistance of Short-term Aging Asphalt Mixture

为了研究短期老化沥青混合料的低温抗裂性能,分析两种不同的沥青混合料老化温度(135℃短期老化4 h、155℃短期老化4 h)以及玄武岩纤维、聚酯纤维、木质素纤维和不同环境温度(0℃、-5℃、-10℃、-20℃)对沥青混合料低温抗裂性能的影响。相对于未老化的沥青混合料,经过短期老化的沥青混合料断裂能均有所下降;掺入聚酯纤维未经过老化的沥青混合料在0℃下的断裂能最高;随着试验温度的降低,半圆弯曲试验(SCB)试件的断裂能整体呈下降趋势。纤维掺料在提高沥青混合料的低温抗裂性能有帮助。

In order to study the low-temperature crack resistance of short-term aging asphalt mixture,the effects of two different bitumen mixture aging temperatures(135℃short-term aging 4 h,155℃short-term aging 4 h),basalt fiber,polyester fiber,lignin fiber and different temperatures(0℃,-5℃,-10℃,-20℃)on the low-temperature cracking resistance of asphalt mixture are analyzed.The fracture energy of asphalt mixture after short-term aging is reduced compared with that of asphalt mixture that is not aged.Unaged asphalt mixtures mixed with polyester fibers have the highest breaking energy at 0℃.With the decrease of test temperature,the fracture energy of SCB specimens showed an overall downward trend.Fiber admixtures are helpful in improving the low-temperature crack resistance of asphalt mixtures.