玄武岩纤维掺量对冷拌环氧沥青混合料性能影响

Influence of basalt fiber content on performance of cold mixed epoxy asphalt mixture

为研究玄武岩纤维掺量对冷拌环氧沥青混合料的影响,基于环氧沥青混合料EA-10级配的骨架空隙特征参数,通过离散元仿真模拟确定玄武岩纤维的最佳长度,选取不同质量分数(0,0.1%,0.3%,0.5%)的玄武岩纤维加入沥青混合料中,通过车辙试验、低温小梁试验、浸水马歇尔试验、冻融劈裂试验及老化试验验证冷拌环氧沥青混合料中玄武岩纤维的最佳掺量。结果表明:玄武岩纤维的最佳掺入长度为6 mm,当其掺加质量分数为0.3%时,对冷拌环氧沥青混合料的性能提升效果最佳。与普通混合料相比,掺纤维后其动稳定度提升50%,抗弯拉强度提升43%,短期和长期老化后的破坏应变分别下降了0.8%,2.7%,紫外老化7 d和15 d的马歇尔稳定度分别下降3.3%和4.2%。

In order to study the influence of basalt fiber content on cold mixed epoxy asphalt mixture,based on the characteristic parameters of skeleton void of epoxy asphalt mixture EA-10 grading,the optimal length of basalt fiber was determined through discrete element simulation,and basalt fiber with different content(0,0.1wt%,0.3wt%,0.5wt%)was selected to be added to asphalt mixtures.The best content of basalt fiber in cold mixed epoxy asphalt mixture was verified by rutting test,low temperature trabecular test,water immersion Marshall test,freeze thaw splitting test and aging test.The results showed that the best mixing length of basalt fiber was 6 mm.When the basalt fiber content was 0.3wt%,the performance improvement effect of the cold mixed epoxy asphalt mixture was the best.Compared with the ordinary mixture,the dynamic stability and flexural tensile strength was increased by 50%and 43%,respectively.The failure strain after short-term and long-term aging was reduced by 0.8%and 2.7%,respectively.The Marshall stability after UV aging for 7 d and 15 d was reduced by 3.3%and 4.2%,respectively.