Evaluation and Improvement of Asphalt Mixture’s Performance at Low Temperature

In order to evaluate and improve the performance of asphalt mixture at low temperature, low-temperature bending test of asphalt mixture was done at first. It was shown that flexural-tensile strength and flexural-tensile strain of different oil-stone ratios reduced under freeze-thaw condition compared to no freeze-thaw condition. The maximum decay rate of flexural-tensile strength is about 18.97% and the maximum decay rate of flexural-tensile strain is about 6.59%. Then six types of polyester fiber were added to asphalt mixture and bending test at low temperature was done. Through the experiment results comparison of fiber asphalt mixtures, it is found that ultimate flexural strain of Good Road II fiber asphalt mixture increases the largest which is up to 12.95%. Ultimate flexural strain of Dolanit AS fiber asphalt mixture increases 8.67% and other fiber asphalt mixtures increase from 3% to 6%. Fiber bridging and fiber micro-reinforced role in the mixture improves the performance of asphalt mixture at low temperature.