高寒地区玄武岩纤维对沥青砼低温抗裂性能研究

Research on the Low-Temperature Crack Resistance Performance of Basalt Fibers in Asphalt Concrete in High-Altitude and Cold Regions

摘要: 久马高速作为高寒地区高速公路，因地区及环境因素影响，平均海拔3000米以上，全年最低温度为零下29.3℃，因此，沥青路面中的低温抗裂性能指标较为关键。国内已有研究发现纤维的添加对沥青混合料的低温抗裂性能有显著提升，基于此研究发现，本文通过在原材料和配合比设计基础上，通过在SMA-13沥青混合料中添加掺量为3%、5%、7%的玄武岩纤维，进行马歇尔试验、低温弯曲试验、车辙试验及浸水马歇尔和冻融劈裂试验，试验结果显示，SMA-13沥青混合料随着玄武岩纤维的掺入，其路用性能得到有效提升。玄武岩纤维掺最为5%时，低温抗裂性能提升至最佳。同时对高寒地区沥青砼各阶段施工温度提出建议。

Abstract: As a highway in high-altitude and cold regions, the Jiuma Expressway has an average altitude of over 3000 meters due to regional and environmental factors, and the lowest temperature throughout the year is minus 29.3˚C. Therefore, the low-temperature crack resistance performance index in asphalt pavement is crucial. There are studies in China that have found that the addition of fibers significantly improves the low-temperature crack resistance of asphalt mixtures. Based on this research, this article found that by adding 3%, 5%, and 7% basalt fibers to SMA-13 asphalt mixtures on the basis of raw materials and mix design, Marshall tests, low-temperature bending tests, rutting tests, immersion Marshall and freeze-thaw splitting tests were conducted. The test results showed that with the addition of basalt fibers, the road performance of SMA-13 asphalt mixtures was effectively improved. When the content of basalt fiber is at most 5%, the low-temperature crack resistance performance is improved to the best. At the same time, suggestions are made for the construction temperature of asphalt concrete in various stages in high-altitude and cold regions.