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为了深化认识半刚性基层沥青路面的温度场及热力学特性,针对大体积堆积材料的结构组成特性,应用基于傅里叶(Fourier)热传导原理开发的“双试件平板式”热传导试验装置,结合实体工程的路面结构和温度场,制备了6种不同配比的水稳基层材料和4种不同类型的沥青面层材料,设定了不同的试验控制温度,测试了水稳混合料和沥青混合料的导热系数,分析了半刚性基层沥青路面的热传导性能。研究结果表明:沥青混合料和水泥稳定碎石混合料的导热系数是一个温变值,随温度的升高而呈线性增加态势;密级配沥青层的导热系数值为1.03~2.10 W/(m·K),密实结构水稳层的导热系数值为1.03~1.60 W/(m·K),前者略大于后者,说明沥青层总体上比水稳层具有更好的导热性能;相同温度条件下,密级配沥青混合料的导热系数值明显大于开级配类型,差别在0.33~1.84 W/(m·K)之间,说明空隙率的影响较大;相同级配类型时,粗粒式沥青混合料的导热系数值大于细粒式,表明石料的传热贡献较大;影响半刚性基层沥青路面导热系数的前提因素是材料种类,影响同类材料的关键因素,首先是空隙率,其次是粒径;沥青路面的热传导通常处于瞬态而非稳态。
In order to deepen the understanding of the temperature field and thermodynamic properties of semi-rigid base asphalt pavement, aiming at the structural characteristics of large-volume accumulation materials, a “double-plate flat-plate” heat conduction testing device based on Fourier heat conduction principle was developed. According to the pavement structure and temperature field of solid engineering, six kinds of water-stable base materials and four different types of asphalt surfacing materials with different proportions were prepared, different test control temperatures were set, water-stable mixtures and asphalt Heat conductivity of the mixture, the thermal conductivity of semi-rigid base asphalt pavement was analyzed. The results show that the thermal conductivity of asphalt mixture and cement stabilized macadam mixture is a temperature change value, which increases linearly with the increase of temperature. The thermal conductivity of dense gradation asphalt layer is 1.03-2.10 W / (m · K). The thermal conductivity of the water-stable structure is 1.03 ~ 1.60 W / (m · K), the former is slightly larger than the latter, which indicates that the asphalt layer has better thermal conductivity than the water stable layer. , The thermal conductivity of the dense graded asphalt mixture is obviously higher than that of the open grading type, with the difference being between 0.33 and 1.84 W / (m · K), indicating that the porosity has a great effect. For the same grading type, the coarse grained The thermal conductivity value of asphalt mixture is larger than that of fine grain, which indicates that the heat transfer contribution of stone is larger. The prerequisites that influence the thermal conductivity of semi-rigid base asphalt pavement are the material types, the key factors affecting the same materials, Particle size; The thermal conductivity of asphalt pavement is usually in transient rather than steady state.