基于改扩建工程的路面温度场对沥青混合料动态模量影响规律

为了研究沥青路面温度场与材料模量的关系,通过实测高速公路改扩建工程旧路与拓宽段路面温度场,分析了沥青路面各结构层的温度变化规律,进而研究了路面结构温度场对沥青混合料动态模量的影响规律。结果表明,沥青路面温度的全年分布呈现双驼峰曲线,分别在5～10°C和25～30°C区间存在两个峰值；路面材料动态模量与温度累积天数之间,随着温度的增加,动态模量呈减小趋势；上、中面层材料存在部分40°C以上的累积天数,此时的材料模量较低。而其他更深结构层次的材料则基本不受40°C以上的影响；随着路面材料模量的变化,早上路面各结构层内温度全天最低,计算出的沥青层底拉应变也最小；下午温度全天最高,计算得到的拉应变也越大。

Influence of Pavement Temperature Field on Dynamic Modulus of Asphalt Mixture Based on Reconstruction Project

In order to study the relationship between asphalt pavement temperature field and material modulus, the temperature variation law of asphalt pavement structure layer is analyzed by measuring the temperature field of asphalt pavement in old road and widening section of expressway reconstruction project, and then the influence law of pavement structure temperature field on dynamic modulus of asphalt mixture is studied. The results show that the annual distribution of asphalt pavement temperature presents a double hump curve, with two peaks at 5 to 10°C and 25 to 30°C respectively. With the increase of temperature, the dynamic modulus of pavement material decreases with the increase of temperature. The upper and middle surface material has a cumulative number of days above 40°C, when the material modulus is lower. Other materials with deeper structure levels are not affected by above 40°C. With the change of pavement material modulus, the temperature in each structure layer of pavement in the morning is the lowest all day, and the calculated tensile strain of asphalt layer is also the lowest. In the afternoon, the temperature is the highest all day, and the strain calculated is larger.