纤维沥青混合料在多年冻土地区的应用

通过两种纤维沥青混合料的马歇尔、低温抗裂、冻融劈裂、高温车辙等试验与试验路修筑观测,分析了纤维沥青混合料在多年冻土地区的适用性。研究得出,在相同沥青含量下,纤维沥青混合料的密度明显减小,空隙率和矿料间隙率增大,沥青饱和度、稳定度和流值有所降低。纤维沥青混合料的蠕变速率及其对沥青含量的敏感性减小,弯拉应变增大,柔性明显增强。在相同沥青含量下,纤维沥青混合料的抗冻性有所降低,但实际应用中通过提高最佳沥青用量,可以缓解这种不利的影响。纤维沥青混合料的动稳定度明显增大,对改善沥青混合料的高温稳定性十分有利。纤维沥青混凝土试验路的裂缝间距明显增大,使用状况良好。结果表明,纤维沥青混合料在多年冻土地区有良好的使用价值。

Application of Fibers-Reinforced Asphalt Mixture to Permafrost Area

Through the testing of Marshell,low-temperature crack resistance,freeze-thaw split,high-temperature rutting of two kinds of fibers-reinforced asphalt mixtures and the testing road observation,the applicability of fibers-reinforced asphalt mixture to permafrost regions is analyzed.The tests show that the density,asphalt degree of saturation,stability and flow value of fibers-reinforced asphalt mixture decrease while the asphalt content is same.The air voids and voids in the mineral aggregate of fibers-reinforced asphalt mixture increase.The speed ratio of creep of fibers-reinforced asphalt mixture and its sensibility to asphalt content diminish,the flexural-tensile strain increases and the flexibility enhances.Although the freezing resistance of fibers-reinforced asphalt mixture depresses when the asphalt content is same,the bad impact will be abated by increasing the optimal asphalt content during the practicing.The dynamic stability of fibers-reinforced asphalt mixture increase evidently.The fibers is quite favorable to improve the high-temperature stability of asphalt mixture.The transverse crack interval of fibers-reinforced asphalt concrete test road is evidently expended,and the employing status is better.The results indicate that the fibers-reinforced asphalt mixture can be favorably used in permafrost regions.