团粒结构对再生沥青混合料路用性能的影响

Effect of Agglomerate Structure on Road Performance of Recycled Asphalt Mixture

再生沥青混合料中存在团粒结构,为了研究团粒结构对再生沥青混合料路用性能的影响,首先对旧料进行抽提,确定旧料级配.采用团粒结构结团程度指标评价旧料中团粒结构的比例.将老化沥青和新的集料等量替换再生沥青混合料中的旧料,模拟团粒结构全部分散的情况,并与采用旧料的再生沥青混合料体积参数和路用性能进行对比.试验结果表明:由于团粒结构的存在,再生沥青混合料空隙率变大,高温性能得到改善,但是低温性能、水稳定性,以及疲劳性能变差.

Aggregate structure exists in recycled asphalt mixture.In order to study the influence of aggregate structure on the road performance of recycled asphalt mixture,the old materials were extracted and the gradation of the old materials was determined.The aggregation degree index of aggregate structure was used to evaluate the proportion of aggregate structure in old materials.The aged asphalt and new aggregate were used to replace the old materials in the recycled asphalt mixture equally,simulating the situation that the aggregate structure was completely dispersed,and comparing with the volume parameters and road performance of the recycled asphalt mixture using the old materials.The test results show that because of the existence of granular structure,the porosity of recycled asphalt mixture increases and the high temperature performance is improved,but the low temperature performance,water stability and fatigue performance become worse.