集热沥青路面性能优化研究

Study on the performance improvement of collecting heat asphalt pavement

冬季路面结冰、夏季路面高温变形等问题严重威胁行车安全和导致路面路用性能下降。近年来提出用集热沥青路面来调节路面温度,通过掺入导热材料提高路面导热性能,但其路用性能较差。因此,平衡路面的导热性能和路用性能成为该技术应用的关键。基于此,本文将钢纤维和石墨复配使用到沥青混凝土中。通过浸水马歇尔稳定度试验、冻融劈裂试验和车辙试验揭示沥青混凝土的水稳定性和高温性能。采用Hot disk热常数分析仪测试沥青路面的导热性能。结果表明,掺入石墨后,沥青混凝土的导热性能明显提高,高温性能增强,但水稳定性明显下降。配合钢纤维使用时,沥青混凝土导热能力相比普通沥青混凝土和仅加入钢纤维的沥青混凝土分别提高35.2%和23.1%,同时路用性能得到提升,达到规范要求。

The problems of icy pavement in winter and high temperature deformation of pavement in summer seriously threaten the safety of traffic and lead to the degradation of pavement performance.In recent years,collecting heat asphalt pavement has been proposed to regulate pavement temperature,which improves the thermal conductivity of the pavement by incorporating thermal conducting materials,but its pavement performance is poor.Therefore,balancing the thermal conductivity and pavement performance has become the key to the application of this technology.Considering it,steel fiber and graphite are applied in this paper.The high temperature performance and moisture stability of asphalt concrete are revealed by immersion Marshall test,freeze-thaw splitting test and rutting test.The thermal conductivity of asphalt pavement is measured by Hot disk thermal constant analyzer.The results show that the thermal conductivity and high-temperature performance of asphalt concrete are significantly improved after the incorporation of graphite,but the moisture stability is significantly decreased.The combination of graphite and steel fiber can improve the thermal conductivity ability by 35.2%and 23.1%,respectively,compared to common asphalt concrete without thermal conductive materials and asphalt concrete only containing steel fiber.Meanwhile,the pavement performance is improved and meets the requirements of the specifications.