水泥与消石灰对沥青胶浆流变性能的影响

Effect of Cement and Slaked Lime on Rheological Properties of Asphalt Mortar

为研究水泥与消石灰替代石灰岩矿粉对沥青胶浆流变性能的影响,采用动态剪切流变仪(DSR)与弯曲梁流变仪(BBR)对矿粉、水泥、消石灰等三种不同填料及其用量的沥青胶浆的高温性能、低温性能进行了试验研究.结果表明:提高粉胶比、采用水泥或消石灰替换石灰岩矿粉对沥青胶浆的高温性能具有显著的增强作用,但其低温性能会降低;随着消石灰替代矿粉比例的增加,沥青胶浆的高温性能持续提高,低温性能则持续下降;当水泥替代矿粉的比例超过20%后,沥青胶浆的高低温性能均不再明显变化;普通密级配沥青混合料的粉胶比宜控制在1.0~1.3,考虑沥青胶浆的高、低温性能及经济性,采用水泥替代矿粉的比例宜不超过20%,采用消石灰替代矿粉的比例宜不超过50%.

In order to study the influence of cement and slaked lime replacing limestone mineral powder on the rheological properties of asphalt mortar,dynamic shear rheometer(DSR)and bending beam rheometer(BBR)were used to test the high temperature and low temperature properties of asphalt mortar with three different fillers including mineral powder,cement and slaked lime.The results show that increasing the ratio of powder to binder and replacing limestone powder with cement or slaked lime can significantly enhance the high temperature performance of asphalt mortar,but its low temperature performance will decrease.With the increase of the proportion of slaked lime replacing mineral powder,the high-temperature performance of asphalt mortar continues to improve,while the low-temperature performance continues to decline.When the proportion of cement replacing mineral powder exceeds 20%,the high and low temperature performance of asphalt mortar will not change obviously.The powder-binder ratio of ordinary dense graded asphalt mixture should be controlled in 1.0~1.3.Considering the high and low temperature performance and economy of asphalt mortar,the proportion of cement instead of mineral powder should not exceed 20%,and the proportion of hydrated lime instead of mineral powder should not exceed 50%.