物理改性赤泥替代矿粉的沥青混合料路用性能研究

Research on Pavement Performance of Asphalt Mixture with Physical Modified Red Mud Instead of Mineral Powder

摘要: 为了解决赤泥的利用率低造成的堆放占地、污染环境等问题，同时减少不可再生矿产资源的消耗，本研究中将赤泥粉体作为填料代替沥青混合料中的石灰岩矿粉，仅能实现赤泥的有效利用，还能减少不可再生矿产资源的消耗。在先前的研究中已经制备了使用物理改性赤泥替代矿粉的沥青胶浆并评价了其流变性能和水稳定性。但是，赤泥对沥青混合料的路用性能的影响尚不清楚。本研究通过将物理改性赤泥替代矿粉填料制备沥青混合料并研究赤泥对沥青胶浆路用性能的影响规律。本研究通过使用浸水马歇尔试验、汉堡车辙试验、SPT试验分别用于评价赤泥沥青混合料的水稳定性、抗车辙性能和动态力学响应。试验结果表明，石灰石矿粉、消石灰、水泥具有相似的氧化物组成，说明水泥和消石灰有可能改善赤泥与沥青的粘结性能；在赤泥中掺入消石灰、水泥会提高赤泥沥青混合料的水稳定性，赤泥替代矿粉可以提高沥青混合料的高温抗车辙性能，而在赤泥中掺入消石灰可以进一步提高其高温性能。在赤泥中掺入少量消石灰或水泥，可以使得动态模量达到普通沥青混合料的水平。试验结果表明，使用本研究制得的物理改性赤泥，可以提高沥青混合料的路用性能。

Abstract: In order to solve the problems of stacking land occupation and environmental pollution caused by low utilization rate of red mud, and reduce the consumption of non renewable mineral resources, red mud powder is used as filler instead of limestone powder in asphalt mixture in this study, which can only realize the effective utilization of red mud, but also reduce the consumption of non renewable mineral resources. In the previous study, asphalt mortar using physical modified red mud instead of mineral powder has been prepared and its rheological properties and water stability have been evaluated. However, the influence of red mud on the road performance of asphalt mixture is not clear. In this study, physical modified red mud was used to replace mineral powder filler to prepare asphalt mixture, and the influence of red mud on the road performance of asphalt mortar was studied. In this study, immersion Marshall test, Hamburg rutting test and SPT test are used to evaluate the water stability, anti rutting performance and dynamic mechanical response of red mud asphalt mixture. The test results show that limestone powder, hydrated lime and cement have similar oxide composition, which indicates that cement and hydrated lime may improve the bonding performance between red mud and asphalt; adding hydrated lime and cement into red mud can improve the water stability of red mud asphalt mixture; replacing mineral powder with red mud can improve the high temperature anti rutting performance of asphalt mixture, while adding hydrated lime into red mud it can further improve its high temperature performance. Adding a small amount of hydrated lime or cement into red mud can make the dynamic modulus reach the level of ordinary asphalt mixture. The test results show that the physical modified red mud can improve the road performance of asphalt mixture.