摘要
为预防与减少沥青路面水损害的发生,以表面能理论为基础、全国六大区域主要城市月平均气温为依据,结合表面能试验和宏观水稳定性试验两种评价方法来准确评价多温度条件下沥青混合料的水稳定性.首先,测试-20～50℃区间内原材料表面能,确定各温度条件下黏附性评价指标ER值;选用 4种沥青混合料进行-20℃的 5次冻融循环劈裂试验、10℃和30℃的浸水马歇尔试验以及50℃的浸水汉堡车辙试验,并借助以上3种宏观试验指标及其技术要求,依次确定对应于各温度点的指标ER阈值.试验结果表明:在-20、10、30、50℃条件下,基质沥青混合料的指标ER阈值分别为0.992、1.693、0.994和0.512;改性沥青混合料的指标ER阈值分别为1.562、1.944、1.144和0.512.进而以多温度条件下沥青混合料水稳定性评价指标阈值为基础,建立基质沥青混合料阈值与温度的关系模型为 y=-0.0006x2+0.0097x+1.4726;改性沥青混合料阈值与温度的关系模型为y=-0.0006x2+0.0004x+1.8341,其中x为温度,y为对应温度条件下的指标阈值.
Abstract
To prevent and reduce the moisture damage of asphalt pavement,based on the surface energy theory and the monthly average temperature of major cities in six regions of China,two evaluation methods,including surface energy test and macroscopic moisture stability test,were combined to accurately evaluate the water stability of asphalt mixture under multi-temperature conditions.First,the surface energy of raw materials was tested in the temperature range of-20 to 50℃to determine the value of adhesive evaluation index ER(Energy Ratio)at various temperatures.Four types of asphalt mixtures were selected for five freeze-thaw cycles splitting tests at-20℃,immersion Marshall tests at 10℃and 30℃,and immersion Hamburg rut tests at 50℃.According to the test indexes determined by the above three macroscopic tests and their corresponding technical requirements,the threshold values of ER corresponding to each temperature were determined.The experimental results show that the threshold values of ER of the asphalt mixture without modifiers at-20,10,30,50℃are 0.992,1.693,0.994 and 0.512,respectively.The threshold values of ER of modified asphalt mixture are 1.562,1.944,1.144 and 0.512,respectively.Furthermore,based on the threshold values of asphalt mixture water stability evaluation index under multi-temperature conditions,the relationship model between threshold value of asphalt mixture without modifiers and temperature was established as y=-0.000 6x2+0.009 7x+1.472 6,and the relationship model between threshold value of modified asphalt mixture and temperature is y=-0.000 6x2+0.000 4x+1.834 1,in which the x indicates temperature and y indicates the corresponding threshold value.
维普
万方数据